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Liability & responsibility of electrician?

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John E.

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Jul 5, 2009, 2:40:18 AM7/5/09
to
I have been asked to offer an opinion in a sensitive situation.

A machinist moved his shop across town and required some rewiring (3-phase
outlets, conduit, etc.) in order to locate some machines where he wanted
them.

He hires a guy who's not a pro (and later discovers is not insured) but has
done shop wiring before and had a good attitude and track record. The guy
does good work. No complaints about the quality of his work.

Owner throws the switch, all works fine.

The story continues 4 weeks later when the very expensive CNC fries its
controller PCB to the tune of $4000.

Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
power supply were set for 220.

What is the legal and moral responsibility of each party?

What will not be helpful are replies about the character or intelligence of
either of the players or their actions.

Thanks.
--
John English

Spehro Pefhany

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Jul 5, 2009, 2:58:00 AM7/5/09
to

IMO, 11% high voltage over nominal should not "fry" the controller
board in the first place.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Phil Allison

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Jul 5, 2009, 3:13:32 AM7/5/09
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"John E."

>
>I have been asked to offer an opinion in a sensitive situation.
>
> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but
> has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.
>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>
> Turns out the voltage in the shop was upward of 245 and the taps in the
> CNC's
> power supply were set for 220.
>
> What is the legal and moral responsibility of each party?


** What a STUPID troll !!!

The PSU in the CNC blew cos it was a pile of shit PLUS the design was 100%
incompetant cos it gave no protection to the delicate and expensive load.

Bet it was old and way past use by date too.

Piss off TROLL !!


.... Phil

Archimedes' Lever

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Jul 5, 2009, 3:45:37 AM7/5/09
to
On Sun, 5 Jul 2009 17:13:32 +1000, "Phil Allison" <phi...@tpg.com.au>
wrote:


Probably a good call, since modern switchers, which the DC supplies
for these things usually are, can handle up to about 265 volts. Even a
bit more, typically.

Bruce L. Bergman

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Jul 5, 2009, 3:56:03 AM7/5/09
to
On Sat, 4 Jul 2009 23:40:18 -0700, John E. <inco...@xbjcd.com>
wrote:

The nominal utility power as supplied is supposed to be 240V. 5
volts over is a touch hot, but not out of the bounds of normal
tolerances - turn everything on in the neighborhood some hot August
afternoon with the AC units cranked, and tell me what the voltage
reads then...

If they were seeing 250V - 255V or more, then I'd call the Utility
and get the transformer taps knocked down a notch.

If the power supply on the CNC computer had changeable taps, and the
last guy that touched it didn't have any reason to look to see what it
was set for, IMHO it's nobody's fault. Especially if the shop they
moved from and the one they moved to had the same nominal operating
voltage, and they knew it - I'm not going to open 50 machines looking
for the unexpected when I'm charging by the hour unless I have a good
reason to... Just "Git Er Done" and go home.

If he had a reason to look inside and saw it was on the 220V tap he
should have moved it to the 240V - or told the owner - it's good
practice to follow but there's no responsibility to look involved.

And I wouldn't expect 255V on the 220V tap to kill it. Now if it
was set for 208V input and you fed it off the 'High Leg' from an Open
Delta service that's hovering around 280V to ground, THEN I'd expect
fireworks. Open Delta High Leg voltages can bounce around and go even
higher, then something flashes over...

That would be the /one/ time I'd call it against the Handyman,
putting the high leg on the control circuit would be a big goof. You
are supposed to put the regular 240V legs on the A and C phases coming
in, and the 'High Leg' Orange lead to B phase and NOT the controls.

The average power supply is supposed to feed +5V, +12V & -12V etc.
to the computer board, and have Crowbar protection so that's all that
gets through. If the supply blows up and lets line voltage through to
fry the controller board (even if you put an over-voltage on the
input) that's a badly built power supply.

Otherwise, it's entirely possible that it just reached End Of Life
and decided to go out in a spectacular manner, and the move had
nothing to do with it. The timer that makes things blow up three days
out of warranty finally went off.

Unless you want to spend a lot of money on Electronic Forensics to
analyze the power supply failure, "The world may never know..."

--<< Bruce >>--

PS - Have to trim off alt-r.c.m to make this go, 4 crosspost limit.

Phil Allison

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Jul 5, 2009, 4:06:17 AM7/5/09
to

"Archimedes' Lever"
"Phil Allison"

>
>>"John E."
>>>
>>>I have been asked to offer an opinion in a sensitive situation.
>>>
>>> A machinist moved his shop across town and required some rewiring
>>> (3-phase
>>> outlets, conduit, etc.) in order to locate some machines where he wanted
>>> them.
>>>
>>> He hires a guy who's not a pro (and later discovers is not insured) but
>>> has
>>> done shop wiring before and had a good attitude and track record. The
>>> guy
>>> does good work. No complaints about the quality of his work.
>>>
>>> Owner throws the switch, all works fine.
>>>
>>> The story continues 4 weeks later when the very expensive CNC fries its
>>> controller PCB to the tune of $4000.
>>>
>>> Turns out the voltage in the shop was upward of 245 and the taps in the
>>> CNC's
>>> power supply were set for 220.
>>>
>>> What is the legal and moral responsibility of each party?
>>
>>
>>** What a STUPID troll !!!
>>
>>The PSU in the CNC blew cos it was a pile of shit PLUS the design was
>>100%
>>incompetant cos it gave no protection to the delicate and expensive load.
>>
>>Bet it was old and way past use by date too.
>>
>>Piss off TROLL !!
>>
>
> Probably a good call, since modern switchers, which the DC supplies
> for these things usually are, can handle up to about 265 volts. Even a
> bit more, typically.


** Unlikely it was a SMPS based on the OP's admittedly poor and incomplete
info.

Cos SMPS do not have multi-taps for AC input voltage - PLUS if an
off-line switcher fails from overvoltage, it just blows the fuse and goes
dead.

But losing regulation and over-voltaging the load ( as was alleged by the
OP) is another scenario altogether - more often associated with old age or
the failure of one of a few critical components in the regulation loop.

..... Phil


Larry The Snake Guy

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Jul 5, 2009, 5:04:47 AM7/5/09
to
On Jul 5, 2:40 am, John E. <incogn...@xbjcd.com> wrote:
> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.

As others have said, there's not much the wiring guy could have done
wrong to get 245 volts rather than 220. He hooked up what was there
and couldn't be expected to have detailed knowledge of what the owner
was going to run, what setting he had it on or how sensitive it was.

Does the owner have some reason to believe that this was not the
voltage in the new shop before the additions?

Richard J Kinch

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Jul 5, 2009, 5:14:21 AM7/5/09
to
John E. writes:

> What is the legal and moral responsibility of each party?

None. It is George Bush's fault.

Geoffrey S. Mendelson

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Jul 5, 2009, 5:54:04 AM7/5/09
to
John E wrote:

> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.

It is the owner of the shop to make sure the electrician he hired was licensed
and if needed insured. Since you did not say where this happened, I can only
make a blanket statement.

If the "guy" represneted himself as a licensed electrictian, then there may
be some criminal liability here for fraud. If he did not claim to be licensed,
or the owner of the business knew that he was not licensed, he is free and
clear.

If the owner hired him knowing he was not licensed, then it was his
responsability to hire a licensed electrician to inspect the work before
he "threw the switch". If he did not, he may be subject to criminal and
civil penalties, have his electricity turned off, etc.

>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>
> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.


And how do you know that? What device did you use to measure the voltage.
Assuming the voltmeter was accurate to 2% and rounded up, 240 volts would read
245. The difference is negligable anyway.

As for the voltage setting on the device, it's not the "wiring guy's" job.

Would you want some random "handyman" poking around inside of an expensive
CNC machine?

> What is the legal and moral responsibility of each party?

I am not a lawyer, but from my (mis)understanding, as long as the "guy" did
not represent himself as an expert on the machine in question, or as a licensed
electrician, ALL of the responsability falls on the owner of the business and
none on the "guy" or anyone's insurance company.


> What will not be helpful are replies about the character or intelligence of
> either of the players or their actions.

Well, I'm going to make one. If the "guy" was up front about his not being
licensed, nor trained on the insides of the CNC machine, he is of good
character and reasonable intelligence.

Let's just say that the person who hired him was also of good character and
intelligence, but ignorant of the law and the requirments of equipment.

He's lucky that all he suffered was one $4000 board failing, not his
entire factory burning down around him with no insurance.

If in the future, he does not hire a licensed electrician to perform the
necessary inspections, etc, nor a properly trained technician to inspect
the equipment, you can say something very different.

I also think it is fair to assume that he has by now had a licensed electrician
in to inspect the work, and a trained technicain in to check all of his
equipment. If he has not done both.........


BTW, if both locations are connected to the same "power grid", it is
unlikely that the line voltage was 220 volts in the old location and 240
in the new one.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel g...@mendelson.com N3OWJ/4X1GM

Andrew VK3BFA

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Jul 5, 2009, 8:04:00 AM7/5/09
to

Tempting as it is to blame your Mr Bush for all the eveils of the
world, including my hens not laying, I would propose the following:
1.As noted, the main supply voltage is nominal, variations are normal
and to be expected.
2.Possibly, if the machine was let stand for a while in the unpowered
position, and it was an old controller (and with a linear power
supply, it probably was,) then the electrolytics in the power supply
could have failed due high ESR, and then it lost regulation and fried
the board.
3.My humble opinion is to just mark write it off to bad luck.
Otherwise, get the lawyers involved for years and huge amounts of
money......

Andrew VK3BFA

Andrew VK3BFA

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Jul 5, 2009, 8:04:38 AM7/5/09
to
On Jul 5, 4:40 pm, John E. <incogn...@xbjcd.com> wrote:

Tempting as it is to blame your Mr Bush for all the eveils of the

Archimedes' Lever

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Jul 5, 2009, 8:16:35 AM7/5/09
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On Sun, 5 Jul 2009 02:04:47 -0700 (PDT), Larry The Snake Guy
<ldfi...@yahoo.com> wrote:

> He hooked up what was there
>and couldn't be expected to have detailed knowledge of what the owner
>was going to run,

You're an idiot. If you are wiring POWER runs, you had better know
what your loads are, and how they get connected.

Doug Miller

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Jul 5, 2009, 9:22:49 AM7/5/09
to

>BTW, if both locations are connected to the same "power grid", it is
>unlikely that the line voltage was 220 volts in the old location and 240
>in the new one.

Incorrect. Distribution voltages are on the order of a few thousand volts,
stepped down by transformers at the point of service to a few hundred. New
location = different transformer = possibly different service voltage even if
the distribution voltages are exactly the same.

That said, though.... any device designed for 220V should be able to handle
245V.

Doug Miller

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Jul 5, 2009, 9:26:35 AM7/5/09
to
In article <0001HW.C67598E2...@news.sf.sbcglobal.net>, inco...@xbjcd.com wrote:
>I have been asked to offer an opinion in a sensitive situation.
>
>A machinist moved his shop across town and required some rewiring (3-phase
>outlets, conduit, etc.) in order to locate some machines where he wanted
>them.
>
>He hires a guy who's not a pro (and later discovers is not insured) but has
>done shop wiring before and had a good attitude and track record. The guy
>does good work. No complaints about the quality of his work.
>
>Owner throws the switch, all works fine.
>
>The story continues 4 weeks later when the very expensive CNC fries its
>controller PCB to the tune of $4000.

Hard to make the case after 4 weeks that _anything_ the electrician did had
anything to do with this. At four seconds, or even four minutes, I'd consider
it obvious. But four weeks went by, and the owner thinks the electrician
caused this? No way.


>
>Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>power supply were set for 220.

So what? Equipment designed for 220V should be able to handle 245V. It's not
the electrician's responsibility to open the CNC machine to see what it's set
for.

William Sommerwerck

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Jul 5, 2009, 9:31:48 AM7/5/09
to
I would have two simple questions...

1. Did the electrician have any control over the voltage when the system was
rewired?

2. Is it normal for electricians to measure the voltage, and "do something"
about it if it's not correct (if only reporting the problem to the
businessman)?


Geoffrey S. Mendelson

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Jul 5, 2009, 9:39:04 AM7/5/09
to
Doug Miller wrote:
>
> Incorrect. Distribution voltages are on the order of a few thousand volts,
> stepped down by transformers at the point of service to a few hundred. New
> location = different transformer = possibly different service voltage even if
> the distribution voltages are exactly the same.

Yes, BUT, a power company attempts to keep a constant voltage throught their
service area. While the voltage fluctates due to equipment, load, etc, I don't
think you can honestly say that if it is 220 volts on one side of town, the
same "grid" produces 240 on the other side of town. It might be 242 in one
place and 239 in another, but even that's a big difference unless there is
a heavy load in one location and not another.

The EU spec allowing household line voltage to be 240 volts while claiming 230
was to allow the UK to keep their current system while being "in spec" but I
doubt it was intended to allow variations from as much as 220 in one place
and 240 in another within the same country.

Geoffrey S. Mendelson

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Jul 5, 2009, 9:54:05 AM7/5/09
to
William Sommerwerck wrote:
>
> 1. Did the electrician have any control over the voltage when the system was
> rewired?
>
> 2. Is it normal for electricians to measure the voltage, and "do something"
> about it if it's not correct (if only reporting the problem to the
> businessman)?

You missed the point of the original post. The person who did the work was
NOT an electrician, they were a "handyman" hired to do the work.

Since the person never said where they were, it's hard to guess what the
rules are but in (almost?) every jurisdiction that licenses
electricians, a license is needed to do electrical work.

If an unlicensed person does electrical work, the work has to be inspected
by a licensed electrician before the power is turned on. If that was not the
case, there would be no point in licensing electricians, would there?

o...@uakron.edu

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Jul 5, 2009, 10:34:08 AM7/5/09
to
I work on lasers that use a buck/boost with 16 tap possibilities on 3
phase all the time, and I used to use the same units in theatrical
touring service until more modern solid state lasers dominated the
laser show industry. . From that perspective, I'm amazed at the
replies here that have failed to ask two simple questions. I will
state that I never met a house electrician who ever looked at the
rating plate on the gear, although I did have a few that asked about
phase sequences.

Two, I never met a house electrician who ever checked anything
hooked to the pigtail I gave him to connect, including "professional"
rental generator technicians (actually they were the worst) In the
theatrical business, it is up to the touring operator to check the
local guys work, and in most cases, we preferred they stand in a
corner and watch us, after your first blown passbank with 3 or 4 out
of 22 power transistors blown in the laser, you get the idea to check
the taps both preshow and under load condition. In one case I asked
for 220/3, went to lunch, and came out to find 380V European power
from the generator in my distro box, which is why the box had its
own"tagged out" disconnect switch. Its a rotary switch in big modern
generators, easy to mess up.

Questions:

One, Did the "electrician" hook straight to the machine's tappable
control transformers, or did he meet a simple junction box on the
side of the machine. If it were the later, I'd say he's off the
hook. On the other hand if he was staring at a tap strip , he should
have asked. There is also the possibility of a "cascade" of
transformers in some machines, ie little CTs all over the place in the
machine, that need tapped. ??????

Two, Did anybody bother to read the manual chapter on setup? Machine
shop gear needs leveled and "trammed" when moved, its not a simple
matter of tossing a CNC off the truck onto any old pad of concrete and
expecting good parts to tolerances, and the first paragraph usually
reads, something like "check settings" and have appropriate safety
gear. ??????

The fault occurred months down the road, a instant ":poof and shower
of sparks:" would point to the electrician, but months down the road
is lack of due diligence on the part of the owner.

John E.

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Jul 5, 2009, 10:34:12 AM7/5/09
to
> I would have two simple questions...
>
> 1. Did the electrician have any control over the voltage when the system was
> rewired?

No.

> 2. Is it normal for electricians to measure the voltage, and "do something"
> about it if it's not correct (if only reporting the problem to the
> businessman)?

This is the basic question I'm asking. Is it common and regular practice to
inform the owner of a voltage as high as 245? And to suggest that he have
factory personnel come and look at each machine and examine PS taps and such?
And if he had hired a licensed electrician would the electrician likely had
informed the owner of the voltage difference?
--
John English

SteveB

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Jul 5, 2009, 10:49:01 AM7/5/09
to

"John E." <inco...@xbjcd.com> wrote in message
news:0001HW.C67598E2...@news.sf.sbcglobal.net...

Well, that eliminates anything that I would have to add to the conversation.

Steve


William Sommerwerck

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Jul 5, 2009, 10:53:10 AM7/5/09
to
>> 1. Did the electrician have any control over the voltage when the system
>> was rewired?

>> 2. Is it normal for electricians to measure the voltage, and "do
something"
>> about it if it's not correct (if only reporting the problem to the
>> businessman)?

> You missed the point of the original post. The person who did the work was
> NOT an electrician, they were a "handyman" hired to do the work.

I didn't miss the point (I think). He was doing the work of an electrician.
And whether or not he was a licensed electrician, he is still morally
responsible for the quality of his work. (Think Hamurabi.)


> Since the person never said where they were, it's hard to guess what the
> rules are but in (almost?) every jurisdiction that licenses
> electricians, a license is needed to do electrical work.

> If an unlicensed person does electrical work, the work has to be inspected
> by a licensed electrician before the power is turned on. If that was not
the
> case, there would be no point in licensing electricians, would there?

No, there wouldn't be. But if he botched the job, he has to be held
responsible. Doesn't he?

Of course, one might argue that if the person who hired him /knew/ he wasn't
an electrician, and didn't have the work inspected, then he (the hirer) is
responsible for whatever went wrong.


Bob Shuman

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Jul 5, 2009, 11:05:42 AM7/5/09
to
In my opinion, No and no to both your questions below. The result would
likely have been the same.

Bob

"John E." <inco...@xbjcd.com> wrote in message

news:0001HW.C67607F4...@news.sf.sbcglobal.net...

Ignoramus20157

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Jul 5, 2009, 11:13:08 AM7/5/09
to
245 volts is only mildly on the high side and should not cause the
symptom described.

i

Geoffrey S. Mendelson

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Jul 5, 2009, 11:29:04 AM7/5/09
to
John E wrote:

> This is the basic question I'm asking. Is it common and regular practice to
> inform the owner of a voltage as high as 245? And to suggest that he have
> factory personnel come and look at each machine and examine PS taps and such?
> And if he had hired a licensed electrician would the electrician likely had
> informed the owner of the voltage difference?

What you have not said is what was the voltage supposed to be?

Where? Common and regular practice as you call it varies from country to
country.

Also what was the actual voltage at the old location. If it was supposed to
be 240 volts then 245 is well within actual variations, or the calibration
of a meter.

If it was supposed to be 208 or 220 or 308, etc then it is too high.

This to me is starting to get tedious. A simple question of "who was at fault"
has become a "pissing contest" over who can make the most outrageous guess
as to why their champion is guilt free.

IMHO it really boils down to exactly what the owner of the business expected
when he hired "the guy". If he hired someone he knew was unlicensed, he
should have had the work inspected or hired a licensed electrician. Otherwise
he was taking a chance that he would never get caught cheating, and he lost.

As for the CNC device failing, his expectation of "the guy" to open it up
and adjust the voltage tapes is unreasonable. Again he took a chance that
he could move the device without hiring the proper technician to pack it up,
unpack it after arival and set it up. And again, he lost.

Considering the worst outcome of it would have been a fire destroying the
building, everything in it and killing all the people involved, a $4000
controller failure, which was probably not caused by the voltage problem
anyway, is a small price to pay for loosing.

As for insurance, no property insurance will cover damage due to illegal
repairs, etc, which includes uninspected work done by unlicensed electricians,
and no manufacturer will cover damage due to untrained technicians modifying
the equipment (even to move the voltage taps), or damage caused by over
voltage due to an unlicensed electrician wiring the equipment.

There may also be civil and criminal liability here, the best thing to do
IMHO is to have the company and "the guy" come to an agreement where they
will leave him alone, and eat the loss. They will then pay for any repairs
to the equipment and "the work" as legally mandated.

SteveB

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Jul 5, 2009, 11:25:19 AM7/5/09
to

"Ignoramus20157" <ignoram...@NOSPAM.20157.invalid> wrote in message
news:282dnV-elMqZXs3X...@giganews.com...

> 245 volts is only mildly on the high side and should not cause the
> symptom described.
>
> i

But iggy, we have to BLAME someone! The guy hires some unqualified person
to hook up used questionable machinery. The blame has to go somewhere. I
know where I'd direct it.

Steve


Martin Riddle

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Jul 5, 2009, 11:43:38 AM7/5/09
to
Nominal 3 phase voltage is 240v, nothing wrong there.

Sounds like the CNC tap was incorrectly selected. What were the other
options?

I know of ground problems with CNC's and Com cards that can cause the
same problem.

I believe it is something else, 245 is only 11% high, not a really big
issue.

Cheers

"Ignoramus20157" <ignoram...@NOSPAM.20157.invalid> wrote in message
news:282dnV-elMqZXs3X...@giganews.com...

Stuart Wheaton

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Jul 5, 2009, 11:48:30 AM7/5/09
to
John E. wrote:
> I have been asked to offer an opinion in a sensitive situation.
>
> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.
>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>
> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.
>
> What is the legal and moral responsibility of each party?
>
> What will not be helpful are replies about the character or intelligence of
> either of the players or their actions.
>
> Thanks.

4 weeks is a long time. Especially on a used piece of equipment that
has been subjected to the strains and jostling of a cross town move.

Can you prove that the incoming voltage was 245 when the "electrician"
was on site?

Were the field connections made by the "electrician" made to a terminal
strip or to the original tails? IOW, Did he see/know that there were
tap options?

If it took 4 weeks to fail in the new shop, do you know that the old
shop didn't also have an overvoltage situation? Maybe the failure was
75% along before the move.

One of the side effects of the slowdown in manufacturing demand is that
there does appear to be an upward creep of utility supplies, in our
shop, this spring our water pressure began to creep upward to the point
where the TP valves on both water heaters began to dribble. Our supply
voltage is a few volts higher too.

If the "electrician" feels like he did miss something, he probably owes
the owner a pro-rated share of the cost, but if he feels he did the job
within the scope of the work he was hired to do, the owner ought to foot
the bill. Whether the 'electrician' gets future work or references
might factor into this....

Rich.

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Jul 5, 2009, 11:51:12 AM7/5/09
to
Equipment is designed to operate +/- 10% of the nameplate rating. In the
case of taps like what happened here, the taps are supposed to be set by the
electrician to fall within the 10% range. With the taps set at 220v the CNC
machine was good to operate from 218v to 242v. As the power installer, it
was the electrician's responsibility to verify the voltage coming into the
building and adjust the taps on the machine accordingly. He was paid to
correctly hook up power to the machine and failed to do so.


"John E." <inco...@xbjcd.com> wrote in message

news:0001HW.C67598E2...@news.sf.sbcglobal.net...

Jon Danniken

unread,
Jul 5, 2009, 11:54:16 AM7/5/09
to
Bruce L. Bergman wrote:
>
> The nominal utility power as supplied is supposed to be 240V. 5
> volts over is a touch hot, but not out of the bounds of normal
> tolerances - turn everything on in the neighborhood some hot August
> afternoon with the AC units cranked, and tell me what the voltage
> reads then...
>
> If they were seeing 250V - 255V or more, then I'd call the Utility
> and get the transformer taps knocked down a notch.

My drier sees 250VAC. Low voltage stuff in this house gets 125VAC.

Everything is working just fine.

Jon


Wes

unread,
Jul 5, 2009, 12:00:59 PM7/5/09
to
John E. <inco...@xbjcd.com> wrote:

>
>He hires a guy who's not a pro (and later discovers is not insured) but has
>done shop wiring before and had a good attitude and track record. The guy
>does good work. No complaints about the quality of his work.


I'm going to translate this. Hires a guy that isn't a licensed electrician but does do
the job for less than the licensed guys with liability insurance.

Now your friend that was shopping for a free lunch now wants his evening meal paid for.

We don't know the voltage it was running at prior to the move, we don't know the
variability of the supply voltage where it is now.

The handyman wired it to the disconnect. Made sure there was power to that point.

Somewhere after that the machine was powered up. I'm going to assume for the sake of
argument that the handyman got the shop owner or the owners designee to do it. I don't
know any compenent electricans or for that matter decent handymen that will turn on a
complex piece of equipment on their own.

So the owner or designee that has the manuals and such for the machine and should be the
most knowledgeable person in the room is the one that is at fault.

Wes

Geoffrey S. Mendelson

unread,
Jul 5, 2009, 12:09:03 PM7/5/09
to
Rich. wrote:


> He was paid to
> correctly hook up power to the machine and failed to do so.


That was NOT what was stated. From the original post:

"A machinist moved his shop across town and required some rewiring (3-phase
outlets, conduit, etc.) in order to locate some machines where he wanted
them."

If the person was hired to run the wiring, as described above, he had nothing
to do with what was plugged into the outlets and did what he was asked. You
ASSUMED he opened the machine up and connected the wires, something which
was not said.

Since we have no idea of what really was specified, all we can do is speculate.

Rich.

unread,
Jul 5, 2009, 12:12:01 PM7/5/09
to

"John E." <inco...@xbjcd.com> wrote in message
news:0001HW.C67607F4...@news.sf.sbcglobal.net...

>> 2. Is it normal for electricians to measure the voltage, and "do
>> something"
>> about it if it's not correct (if only reporting the problem to the
>> businessman)?
>
> This is the basic question I'm asking. Is it common and regular practice
> to
> inform the owner of a voltage as high as 245? And to suggest that he have
> factory personnel come and look at each machine and examine PS taps and
> such?
> And if he had hired a licensed electrician would the electrician likely
> had
> informed the owner of the voltage difference?
> --
> John English
>

It is not regular practice to inform the owner, unless something is found to
be wrong. Having 245v in the building is not normal, and there is a lot of
equipment out there that does not have taps. Equipment without taps could be
damaged by this higher than usual voltage.

It is the responsibility of the electrician to make sure the equipment he is
wiring can correctly run on the power being supplied. IMO the electrician
did not do his job correctly.

William Sommerwerck

unread,
Jul 5, 2009, 12:24:20 PM7/5/09
to
> My drier sees 250VAC. Low voltage stuff in this house gets 125VAC.
> Everything is working just fine.

<sniff> <sniff> Is that burning cotton I smell?


Jon Danniken

unread,
Jul 5, 2009, 12:29:24 PM7/5/09
to

Drier has a temperature limiter, so although the slightly higher voltage
results in a slightly quicker "turn on" time for the elements, they still
are shut off at the same temperature regardless of incoming voltage.

Jon


Geoffrey S. Mendelson

unread,
Jul 5, 2009, 12:39:04 PM7/5/09
to
Rich. wrote:

>
> It is not regular practice to inform the owner, unless something is found to
> be wrong. Having 245v in the building is not normal, and there is a lot of
> equipment out there that does not have taps. Equipment without taps could be
> damaged by this higher than usual voltage.


Where, no one will say where this is. As for the voltage, here in Israel
230 volts is normal, 245 is not. In the UK, 240 is the "nominal voltage",
245 is less than 3% high and well with the accuracy of a random voltmeter.

In the US, the nominal line voltage is around 127 volts, specified to be
120, BUT the system almost everywhere is a 240 volt 2 phase system, with
one phase to ground being "120" volts and the voltage between them being
"240" volts.


> It is the responsibility of the electrician to make sure the equipment he is
> wiring can correctly run on the power being supplied. IMO the electrician
> did not do his job correctly.


Only if the electrician is hired to hook up the equipment to the power line
and adjust the equipment as needed. If an electrician is hired to run some
conduit with a connection to a panel at one end and an outlet at the other
than there is no responsability for the equipment that may be plugged into
it, or the actual voltage.

Since there was no electrician here, just an unlicensed "handyman", there is
even less liability.

The original poster asked what was reasonable and customary. The answer to that
is:

1. Hire a licensed electrician to run the wire and make sure the outlets are
up to spec according to the applicable law.

2. Hire a technican authorized by the manufacturer of the equipment to
properly pack it up, unpack it after moving and hook it up, making any
adjustments as needed.

For the first, nothing else is legal, and therefore anything else (except
inspection by a licensed electrician) is reasonable.

The second is a little more fluid, but the manufacturer would argue that
using someone who is not authorized to make connections, modify the equipment,
etc voids their warranty, so one can argue that is the customary practice.

I guess you can argue that it is customary to cheat on the license for small
electrical jobs, and the certification of technicians for repairs, etc, but
that custom also carries the burden of accepting responsability for any
damaged caused by the people who do the work.

Leo Lichtman

unread,
Jul 5, 2009, 12:41:33 PM7/5/09
to

"Doug Miller" wrote: (clip) That said, though.... any device designed for
220V should be able to handle
> 245V.
^^^^^^^^^^^^^^^^^
Years ago when household appliances ran on 110 volts, we had 220. Since
then, voltage from neutral to either side rose to about 120, and voltage
across both side rose to 240. For some reason we still talk about 220 as
though it were double 120. What I'm getting at is that systems are no
longer designed for 220--it's 240, so the discrepancy is only 5 volts, and
that's trivial.

I'm guessing that the failure was due to some totally different cause, not
an error in line voltage.


Doug Miller

unread,
Jul 5, 2009, 12:53:25 PM7/5/09
to
In article <slrnh51b3...@cable.mendelson.com>, g...@mendelson.com wrote:
>Doug Miller wrote:
>>
>> Incorrect. Distribution voltages are on the order of a few thousand volts,
>> stepped down by transformers at the point of service to a few hundred. New
>> location = different transformer = possibly different service voltage even if
>> the distribution voltages are exactly the same.
>
>Yes, BUT, a power company attempts to keep a constant voltage throught their
>service area. While the voltage fluctates due to equipment, load, etc, I don't
>think you can honestly say that if it is 220 volts on one side of town, the
>same "grid" produces 240 on the other side of town. It might be 242 in one
>place and 239 in another, but even that's a big difference unless there is
>a heavy load in one location and not another.

You're missing the point. This has nothing to do with the voltage supplied
by the utility. The utility doesn't supply 220V or 240V or whatever. They
supply (for example) 4KV. A transformer at the point of service reduces that
to 220V, or 240V, or whatever. Different transformers connected to the *same*
4KV primary voltage could easily produce different secondary voltages.

Doug Miller

unread,
Jul 5, 2009, 12:56:19 PM7/5/09
to

Assuming a nominal 240VAC supply, 245V is in no way "not correct" -- it's only
about a 2% overvoltage.

Doug Miller

unread,
Jul 5, 2009, 1:02:31 PM7/5/09
to
In article <h2qf18$8mn$1...@news.eternal-september.org>, "William Sommerwerck" <grizzle...@comcast.net> wrote:
>>> 1. Did the electrician have any control over the voltage when the system
>>> was rewired?
>
>>> 2. Is it normal for electricians to measure the voltage, and "do
>something"
>>> about it if it's not correct (if only reporting the problem to the
>>> businessman)?
>
>> You missed the point of the original post. The person who did the work was
>> NOT an electrician, they were a "handyman" hired to do the work.
>
>I didn't miss the point (I think). He was doing the work of an electrician.
>And whether or not he was a licensed electrician, he is still morally
>responsible for the quality of his work. (Think Hamurabi.)

Actually, you *are* missing the important point, which is that it's
_not_his_fault_:

1) 245VAC is *not* a problem in a nominal 240VAC supply.
2) If the equipment is actually labelled 220V, and not 240V, it's *old*.
3) Equipment designed for 220VAC normally operates just fine on 240VAC.
4) If the wiring, or the voltage, were in any way to blame, the failure almost
certainly would have occurred long before it did. Four weeks after the fact, I
can't see how that could be laid at the feet of the guy that did the wiring,
licensed or not.

MooseFET

unread,
Jul 5, 2009, 1:04:03 PM7/5/09
to
On Jul 5, 5:04 am, Andrew VK3BFA <VK3...@wia.org.au> wrote:

> On Jul 5, 4:40 pm, John E. <incogn...@xbjcd.com> wrote:
>
>
>
> > I have been asked to offer an opinion in a sensitive situation.
>
> > A machinist moved his shop across town and required some rewiring (3-phase
> > outlets, conduit, etc.) in order to locate some machines where he wanted
> > them.
>
> > He hires a guy who's not a pro (and later discovers is not insured) but has
> > done shop wiring before and had a good attitude and track record. The guy
> > does good work. No complaints about the quality of his work.
>
> > Owner throws the switch, all works fine.
>
> > The story continues 4 weeks later when the very expensive CNC fries its
> > controller PCB to the tune of $4000.
>
> > Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> > power supply were set for 220.
>
> > What is the legal and moral responsibility of each party?
>
> > What will not be helpful are replies about the character or intelligence of
> > either of the players or their actions.
>
> > Thanks.
> > --
> > John English
>
> Tempting as it is to blame your Mr Bush for all the eveils of the
> world, including my hens not laying, I would propose the following:
> 1.As noted, the main supply voltage is nominal, variations are normal
> and to be expected.

Any reasonable design for the power supply should have defended the
controller board even if the voltage was further out of bounds than
the poster suggested.

That said: I don't think we can blame Bush for this because it didn't
burn down the whole shop in the process.

> 2.Possibly, if the machine was let stand for a while in the unpowered
> position, and it was an old controller (and with a linear power
> supply, it probably was,) then the electrolytics in the power supply
> could have failed due high ESR, and then it lost regulation and fried
> the board.

The capacitors could have also failed in the leaky and then exploding
manner. Having them suddenly go open as they flung their guts all
over the insides could have been the cause.

That said: I don't think we can blame Bush for this because it was
Hillary that swapped all the "N" and "Q" keys on the key boards in the
Whitehouse so it was likely her fault.

> 3.My humble opinion is to just mark write it off to bad luck.
> Otherwise, get the lawyers involved for years and huge amounts of
> money......
>
> Andrew VK3BFA

RoyJ

unread,
Jul 5, 2009, 1:04:07 PM7/5/09
to

>
> Assuming a nominal 240VAC supply, 245V is in no way "not correct" -- it's only
> about a 2% overvoltage.

And since there is likely no load in shop when the install was taking
place, the 245 would be a higher than normal reading.

But I question the use of "3phase" and "245 volts" in the OP question.
Around here, 245 volts would be perfectly normal for a single phase
circuit, very high for a "standard" 208/3 phase delta.

Doug Miller

unread,
Jul 5, 2009, 1:13:14 PM7/5/09
to

OTOH, why would the machine be set up for 220V as described, if intended to be
connected to a 208V supply?

John R. Carroll

unread,
Jul 5, 2009, 1:18:19 PM7/5/09
to

"Doug Miller" <spam...@milmac.com> wrote in message
news:Ma54m.1908$cl4....@flpi150.ffdc.sbc.com...

Because CNC controls are designed to run at 220V plus Zero/minus 5%.
They love straight 208 three phase power because of the balance. You can
usually just change control paremeters without fiddling with the
transformers.

Anyway, this shop owner did it so it's his job now to step in it.

JC


Geoffrey S. Mendelson

unread,
Jul 5, 2009, 1:29:04 PM7/5/09
to
Doug Miller wrote:
> You're missing the point. This has nothing to do with the voltage supplied
> by the utility. The utility doesn't supply 220V or 240V or whatever. They
> supply (for example) 4KV. A transformer at the point of service reduces that
> to 220V, or 240V, or whatever. Different transformers connected to the *same*
> 4KV primary voltage could easily produce different secondary voltages.

No, I'm not. When I lived in the US, (PECO) the electric company sold
me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
dropped down during times of high usage.

They did not supply or sell me 4kv volts, or anything else.

Here it's even simpler. Israel electric sells me 230 volts, 50Hz electicity
and except for just before the power going out it has been that way for 12
years. When I had a UPS monitoring the voltage, it was never more than
1 volt +- spec.

Ok, since you insist would anyone out there who gets 4kv from their local
electric company please raise your hand.

William Sommerwerck

unread,
Jul 5, 2009, 1:38:10 PM7/5/09
to
"Jon Danniken" <jondanS...@yaSPAMhoo.com> wrote in message
news:7bc2n5F...@mid.individual.net...
> William Sommerwerck wrote:


>>> My drier sees 250VAC. Low voltage stuff in this house gets 125VAC.
>>> Everything is working just fine.

>> <sniff> <sniff> Is that burning cotton I smell?


> Drier has a temperature limiter,

It's called a thermostat

> so although the slightly higher voltage
> results in a slightly quicker "turn on" time for the elements, they still
> are shut off at the same temperature regardless of incoming voltage.

Of course. I was jesting.


John Larkin

unread,
Jul 5, 2009, 1:44:13 PM7/5/09
to
On Sun, 05 Jul 2009 02:58:00 -0400, Spehro Pefhany
<spef...@interlogDOTyou.knowwhat> wrote:

>On Sat, 4 Jul 2009 23:40:18 -0700, the renowned John E.
><inco...@xbjcd.com> wrote:
>
>>I have been asked to offer an opinion in a sensitive situation.
>>
>>A machinist moved his shop across town and required some rewiring (3-phase
>>outlets, conduit, etc.) in order to locate some machines where he wanted
>>them.
>>
>>He hires a guy who's not a pro (and later discovers is not insured) but has
>>done shop wiring before and had a good attitude and track record. The guy
>>does good work. No complaints about the quality of his work.
>>
>>Owner throws the switch, all works fine.
>>
>>The story continues 4 weeks later when the very expensive CNC fries its
>>controller PCB to the tune of $4000.
>>
>>Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>>power supply were set for 220.
>>
>>What is the legal and moral responsibility of each party?
>>
>>What will not be helpful are replies about the character or intelligence of
>>either of the players or their actions.
>>
>>Thanks.
>

>IMO, 11% high voltage over nominal should not "fry" the controller
>board in the first place.
>
>

Yes. The controller was overly fragile, or it may have just had a
random failure unrelated to supply voltage. That happens.

If the owner blames the electrician, don't use him again. Sue the
power company for providing 245.


John

krw

unread,
Jul 5, 2009, 1:46:08 PM7/5/09
to
On Sun, 5 Jul 2009 17:29:04 +0000 (UTC), "Geoffrey S. Mendelson"
<g...@mendelson.com> wrote:

>Doug Miller wrote:
>> You're missing the point. This has nothing to do with the voltage supplied
>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>> supply (for example) 4KV. A transformer at the point of service reduces that
>> to 220V, or 240V, or whatever. Different transformers connected to the *same*
>> 4KV primary voltage could easily produce different secondary voltages.
>
>No, I'm not. When I lived in the US, (PECO) the electric company sold
>me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>dropped down during times of high usage.

240V isn't "two phase", rather single phase, or otherwise known as
"split phase". ...and it had better not be 127V (maybe twice that).

>They did not supply or sell me 4kv volts, or anything else.

They supplied that to the pole. Please read.

>Here it's even simpler. Israel electric sells me 230 volts, 50Hz electicity
>and except for just before the power going out it has been that way for 12
>years. When I had a UPS monitoring the voltage, it was never more than
>1 volt +- spec.

Lots of good that does after the power goes out.

>Ok, since you insist would anyone out there who gets 4kv from their local
>electric company please raise your hand.

All of us who can read.

John R. Carroll

unread,
Jul 5, 2009, 1:55:08 PM7/5/09
to

"Wes" <clu...@lycos.com> wrote in message
news:R644m.329994$6p1.3...@en-nntp-02.dc1.easynews.com...

Hey Wes.
If you open up one of your older Fanucs you will see a tag somewhere that
says 200V AC.
That is the design spec.

JC


Plain...@yahoo.com

unread,
Jul 5, 2009, 2:11:16 PM7/5/09
to
On Sat, 4 Jul 2009 23:40:18 -0700, John E. <inco...@xbjcd.com>
wrote:

>I have been asked to offer an opinion in a sensitive situation.
>
>A machinist moved his shop across town and required some rewiring (3-phase
>outlets, conduit, etc.) in order to locate some machines where he wanted
>them.
>

>He hires a guy who's not a pro (and later discovers is not insured) but has
>done shop wiring before and had a good attitude and track record. The guy
>does good work. No complaints about the quality of his work.
>

>Owner throws the switch, all works fine.
>
>The story continues 4 weeks later when the very expensive CNC fries its
>controller PCB to the tune of $4000.
>
>Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>power supply were set for 220.
>
>What is the legal and moral responsibility of each party?
>
>What will not be helpful are replies about the character or intelligence of
>either of the players or their actions.
>
>Thanks.

First of all, 245 VAC is a common AC voltage in the US. Yes, I know
we say 110 / 220, but it is more like 120 / 240.

Second, what was the 'handyman' hired to do? If he wired a number of
1 and 3 phace 110 / 220 volt outlets, he has no liability. If he
hard-wired (ran conduit directly to) the equipment, it is open to
discussion. If he adjusted wiring taps, etc than he MAY be
responsible.

However, every controller I have ever seen uses a regulated power
supply. Decades ago my employer built them. We tested the supplies
at full load while varying input voltage from 20% below nominal to 20%
above nominal voltage (90 - 130 VAC). If the equipment operated for 4
weeks, I would say the 'handyman' is not responsible.

PlainBill

Larry The Snake Guy

unread,
Jul 5, 2009, 2:11:42 PM7/5/09
to
At this point, I think there are two questions (at least) that we need
to OP to answer.

1) Did the "wiring guy" hook up the equipment or just run wiring to
the locations where it was to go? And if he hooked up the equipment,
did this require opening it or did the owner just tell him to connect
cables that were already attached to the machines.

2) What were the agreed upon responsibilities of the "guy"? I assume
the owner hired him to save money, so he might be expected to do as
little as necessary to set things up, unless something more was agreed
upon. Asking what a licensed electrician would normally do might not
really be relevant...

Also, don't forget that in most places if the owner knew he hired an
unlicensed person, he (the owner) is probably liable for fines,
permits (possibly at doube the price) and at least having all this
work gone over by a real electrician if the authorities find out. If
it's anything like residential work, they might even force him to pay
a licensed electrician to rip it all out and redo it. I'd consider
that before raising a stink.

Rich.

unread,
Jul 5, 2009, 2:28:27 PM7/5/09
to
"Doug Miller" <spam...@milmac.com> wrote in message
news:I054m.1906$cl4....@flpi150.ffdc.sbc.com...

> In article <h2qf18$8mn$1...@news.eternal-september.org>, "William
> Sommerwerck" <grizzle...@comcast.net> wrote:
>
> 1) 245VAC is *not* a problem in a nominal 240VAC supply.


That is correct until you factor in that the taps were set to 220v. If the
taps were set at 240, then 245v would never have been a problem.

rangerssuck

unread,
Jul 5, 2009, 2:31:43 PM7/5/09
to
On Jul 5, 2:11 pm, PlainBil...@yahoo.com wrote:
> On Sat, 4 Jul 2009 23:40:18 -0700, John E. <incogn...@xbjcd.com>

> wrote:
>
>
>
> >I have been asked to offer an opinion in a sensitive situation.
>
> >A machinist moved his shop across town and required some rewiring (3-phase
> >outlets, conduit, etc.) in order to locate some machines where he wanted
> >them.
>
> >He hires a guy who's not a pro (and later discovers is not insured) but has
> >done shop wiring before and had a good attitude and track record. The guy
> >does good work. No complaints about the quality of his work.
>
> >Owner throws the switch, all works fine.
>
> >The story continues 4 weeks later when the very expensive CNC fries its
> >controller PCB to the tune of $4000.
>
> >Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> >power supply were set for 220.
>
> >What is the legal and moral responsibility of each party?
>
> >What will not be helpful are replies about the character or intelligence of
> >either of the players or their actions.
>
> >Thanks.
>
> First of all, 245 VAC is a common AC voltage in the US.  Yes, I know
> we say 110 / 220, but it is more like 120 / 240.  
>
> Second, what was the 'handyman' hired to do?  If he wired a number of
> 1 and 3 phace 110 / 220 volt  outlets, he has no liability.  If he
> hard-wired (ran conduit directly to) the equipment, it is open to
> discussion.  If he adjusted wiring taps, etc than he MAY be
> responsible.

Just to muddy it up even further, we recently put a medical device
through CE approval and were advised by the examiner that our label
should read "110/240", and that's the label we passed with.

>
> However, every controller I have ever seen uses a regulated power
> supply.  Decades ago my employer built them.  We tested the supplies
> at full load while varying input voltage from 20% below nominal to 20%
> above nominal voltage (90 - 130 VAC).  If the equipment operated for 4
> weeks, I would say the 'handyman' is not responsible.

Fully agreed.

>
> PlainBill

Tom Horne

unread,
Jul 5, 2009, 2:37:23 PM7/5/09
to

Roy
Three phase delta would not produce 208 volts unless it was a customer
provided special purpose transformer. Three Phase Delta can be wired
as corner grounded, grounded center tap in one phase with the opposite
phase being the odd higher voltage to ground known as the wild leg or
stinger, or completely ungrounded with or without ground fault
detection. The way you end up with three phase 208 is to wire the
transformer in a wye or star configuration with the transformer
primary taps set to produce 120 volts to ground on each of the three
secondary legs.
--
Tom Horne

daestrom

unread,
Jul 5, 2009, 2:39:27 PM7/5/09
to
krw wrote:
> On Sun, 5 Jul 2009 17:29:04 +0000 (UTC), "Geoffrey S. Mendelson"
> <g...@mendelson.com> wrote:
>
>> Doug Miller wrote:
>>> You're missing the point. This has nothing to do with the voltage supplied
>>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>>> supply (for example) 4KV. A transformer at the point of service reduces that
>>> to 220V, or 240V, or whatever. Different transformers connected to the *same*
>>> 4KV primary voltage could easily produce different secondary voltages.
>> No, I'm not. When I lived in the US, (PECO) the electric company sold
>> me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>> dropped down during times of high usage.
>
> 240V isn't "two phase", rather single phase, or otherwise known as
> "split phase". ...and it had better not be 127V (maybe twice that).
>
>> They did not supply or sell me 4kv volts, or anything else.
>
> They supplied that to the pole. Please read.
>

What they carry on the pole is immaterial. What they supply to the
customer service entrance is the 'point of sale'.

Very few homes or light commercial service is in the 4kV range in the
US. The service entrance voltage is usually much lower, 240 or 480. In
these cases, the step-down transformer used to convert from distribution
voltage (e.g. 4kV) to the service entrance voltage is the utility's
responsibility.

The utility is responsible for supplying the voltage/frequency at the
service entrance / metering point of sale, not 'the pole'.

daestrom

krw

unread,
Jul 5, 2009, 2:55:49 PM7/5/09
to
On Sun, 05 Jul 2009 14:39:27 -0400, daestrom <daes...@twcny.rr.com>
wrote:

>krw wrote:
>> On Sun, 5 Jul 2009 17:29:04 +0000 (UTC), "Geoffrey S. Mendelson"
>> <g...@mendelson.com> wrote:
>>
>>> Doug Miller wrote:
>>>> You're missing the point. This has nothing to do with the voltage supplied
>>>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>>>> supply (for example) 4KV. A transformer at the point of service reduces that
>>>> to 220V, or 240V, or whatever. Different transformers connected to the *same*
>>>> 4KV primary voltage could easily produce different secondary voltages.
>>> No, I'm not. When I lived in the US, (PECO) the electric company sold
>>> me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>>> dropped down during times of high usage.
>>
>> 240V isn't "two phase", rather single phase, or otherwise known as
>> "split phase". ...and it had better not be 127V (maybe twice that).
>>
>>> They did not supply or sell me 4kv volts, or anything else.
>>
>> They supplied that to the pole. Please read.
>>
>
>What they carry on the pole is immaterial. What they supply to the
>customer service entrance is the 'point of sale'.

It is material to what the OP wrote. It may be immaterial to the
facts of the case, but it *is* what was written.

>Very few homes or light commercial service is in the 4kV range in the
>US. The service entrance voltage is usually much lower, 240 or 480. In
>these cases, the step-down transformer used to convert from distribution
>voltage (e.g. 4kV) to the service entrance voltage is the utility's
>responsibility.

That may be, but that wasn't what was written. The step down
transformer was part of the post too.


>The utility is responsible for supplying the voltage/frequency at the
>service entrance / metering point of sale, not 'the pole'.

Irrelevant to what was written and objections to same.

Esther & Fester Bestertester

unread,
Jul 5, 2009, 3:29:36 PM7/5/09
to
> This to me is starting to get tedious.

The standard USENET rule applies:

THEN DON'T RESPOND.

John E.

unread,
Jul 5, 2009, 3:33:10 PM7/5/09
to
USA, N. American continent, planet Earth.

whit3rd

unread,
Jul 5, 2009, 3:43:00 PM7/5/09
to
On Jul 5, 6:26 am, spamb...@milmac.com (Doug Miller) wrote:

> >Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> >power supply were set for 220.
>

> So what? Equipment designed for 220V should be able to handle 245V. It's not
> the electrician's responsibility to open the CNC machine to see what it's set
> for.

Absolutely correct. The CNC controller burned up, BUT the line
voltage
is no smoking gun, you have NO reason to believe that was the cause.
Overvoltage would usually result in relatively simple, inexpensive
faults (fuses blowing), or at most a power supply failure (figure
$300 for that kind of part, no WAY it's $4000).

Manufacturer of the controller should be replacing it under warranty.
And, there should be an install procedure to determine tap placement:
who
did the install? Wiring an outlet for the equipment does NOT make
the electrician responsible for install procedure, nor for installed
equipment.

ehsjr

unread,
Jul 5, 2009, 4:11:53 PM7/5/09
to
John E. wrote:
> I have been asked to offer an opinion in a sensitive situation.

BZZZT! Danger Will Robinson!

Before offering your opinion, examine what *you* stand to
gain/lose.

The "sensitive situation" could be a bucket of rattlesnakes,
and your participation might direct some of those snakes
your way.

Someone is looking at you as the "expert" whose opinion
carries weight in his/her mind. Your opinion is bound
to be used to bolster the argument of whichever side
asked you: "Well John said ... "
That bolstering could get you in trouble with the other
person - and it is likely or possible that whatever you
say will be misquoted.

Taking sides in a "sensitive situation" is fraught with
danger.

The next issue is that you are not sure enough of your
opinion to voice it without seeing what people here
think. Or, if you have already voiced it, you have
enough doubt to seek other's viewpoints here. Either
way, it highlights the problem(s) that sensitive
situations create.

If, for the moment, we take the possible danger to you
out of the equation and just look at the situation:
Who can tell? Does anyone replying to the post have
all of pertinent the facts? We don't know the details
of the agreement between the handyman and the shop
owner, whether there was any specific discussion concerning
the CNC machine, what claims the handyman made as to his
experience or expertise, any applicable laws in the location
the work was done, whether/if/when the power utility changed
things and on and on. People could reply with 100% valid
opinions that might not apply to the specific situation.
So, while there may be a clear legal and moral responsibility
for each party, it is impossible for us to to know what it is
at this point.

Ed


>
> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.
>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>

> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.
>

Gunner Asch

unread,
Jul 5, 2009, 4:37:22 PM7/5/09
to
On Sun, 05 Jul 2009 16:53:25 GMT, spam...@milmac.com (Doug Miller)
wrote:

>
>You're missing the point. This has nothing to do with the voltage supplied
>by the utility. The utility doesn't supply 220V or 240V or whatever. They
>supply (for example) 4KV. A transformer at the point of service reduces that
>to 220V, or 240V, or whatever. Different transformers connected to the *same*
>4KV primary voltage could easily produce different secondary voltages.


Indeed it does.

My single phase home 220 volt service runs between 245-252 volts

Pacific Greed and Extortion claims that is nominal and within spec for
home wiring.

Fortunately..most of my gear runs fine on this, with the exception of
the VFD on my Gorton mill. At times, it shows an over voltage alarm and
refuses to run until the voltage drops back down to under 246.

Ive called this to the attention of the local PG&E wanks..and they
simply shrug, send someone out to measure the voltage, confirm that
indeed its 252, blither a bit and then leave.

gunner

"Lenin called them "useful idiots," those people living in
liberal democracies who by giving moral and material support
to a totalitarian ideology in effect were braiding the rope that
would hang them. Why people who enjoyed freedom and prosperity worked
passionately to destroy both is a fascinating question, one still with us
today. Now the useful idiots can be found in the chorus of appeasement,
reflexive anti-Americanism, and sentimental idealism trying to inhibit
the necessary responses to another freedom-hating ideology, radical Islam"

Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno

Gunner Asch

unread,
Jul 5, 2009, 4:44:18 PM7/5/09
to
On Sun, 5 Jul 2009 13:54:05 +0000 (UTC), "Geoffrey S. Mendelson"
<g...@mendelson.com> wrote:

>
>You missed the point of the original post. The person who did the work was
>NOT an electrician, they were a "handyman" hired to do the work.


We must ask you at this point...what is your definition of an
electrician.

If the same person gets a license, does that automatically make him no
longer a handyman, but an electrician?

Gunner

Geoffrey S. Mendelson

unread,
Jul 5, 2009, 4:54:04 PM7/5/09
to
Gunner Asch wrote:
> Fortunately..most of my gear runs fine on this, with the exception of
> the VFD on my Gorton mill. At times, it shows an over voltage alarm and
> refuses to run until the voltage drops back down to under 246.
>
> Ive called this to the attention of the local PG&E wanks..and they
> simply shrug, send someone out to measure the voltage, confirm that
> indeed its 252, blither a bit and then leave.

Before there were UPS's there were constant voltage transformers, the most
popular made by Sola. UPS's put out really crap AC, and are designed to
work with a switching power supply as a load.

Sola transformers were used with all sorts of things, there may be one that
fits your needs. I used them with computers that had linear power supplies,
but I think they will work with motors, it's worth checking out.

Geoffrey S. Mendelson

unread,
Jul 5, 2009, 5:04:04 PM7/5/09
to
Gunner Asch wrote:

> We must ask you at this point...what is your definition of an
> electrician.

Someone who has a license, (and/or) is a member of the union, passed a
test that entitles him to call himself an electrician.

But not someone with no formal training, licensure or certification.

lang...@fonz.dk

unread,
Jul 5, 2009, 5:07:22 PM7/5/09
to
On 5 Jul., 08:58, Spehro Pefhany <speffS...@interlogDOTyou.knowwhat>
wrote:
> On Sat, 4 Jul 2009 23:40:18 -0700, the renowned John E.

>
>
>
> <incogn...@xbjcd.com> wrote:
> >I have been asked to offer an opinion in a sensitive situation.
>
> >A machinist moved his shop across town and required some rewiring (3-phase
> >outlets, conduit, etc.) in order to locate some machines where he wanted
> >them.
>
> >He hires a guy who's not a pro (and later discovers is not insured) but has
> >done shop wiring before and had a good attitude and track record. The guy
> >does good work. No complaints about the quality of his work.
>
> >Owner throws the switch, all works fine.
>
> >The story continues 4 weeks later when the very expensive CNC fries its
> >controller PCB to the tune of $4000.
>
> >Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> >power supply were set for 220.
>
> >What is the legal and moral responsibility of each party?
>
> >What will not be helpful are replies about the character or intelligence of
> >either of the players or their actions.
>
> >Thanks.
>
> IMO, 11% high voltage over nominal should not "fry" the controller
> board in the first place.  
>

a loose neutral can result in all kinds of strange voltages depending
on the load on the
phases, so the 11% might just be what the voltage was when it was
measured, not what
it was when the controller was fried

-Lasse

john

unread,
Jul 5, 2009, 6:06:56 PM7/5/09
to
John E. wrote:
> I have been asked to offer an opinion in a sensitive situation.
>
> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.
>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>
> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.
>
> What is the legal and moral responsibility of each party?
>
> What will not be helpful are replies about the character or intelligence of
> either of the players or their actions.
>
> Thanks.

The failure that you had was probably caused by your rigger not using an
airride trailer to move the equipment and something got shaken up. Four
weeks of running proves the voltage was not the problem. Some
disgruntled employee probably pissed in the cabinet.


245 volts is within the normal specs from the utility. AS far as
changing the tap, you should have called in a machine tech to set it up.
An electrician wires only to the safety disconnect switch in the
machine, after that it is your responsibility to call in a machine setup
tech.


John

Gunner Asch

unread,
Jul 5, 2009, 6:16:00 PM7/5/09
to
On Sun, 5 Jul 2009 21:04:04 +0000 (UTC), "Geoffrey S. Mendelson"
<g...@mendelson.com> wrote:

>Gunner Asch wrote:
>
>> We must ask you at this point...what is your definition of an
>> electrician.
>
>Someone who has a license, (and/or) is a member of the union, passed a
>test that entitles him to call himself an electrician.
>
>But not someone with no formal training, licensure or certification.
>
>Geoff.

So then what am I? I passed the tests, at one time held a (California)
C7 and C10 license, ( as responsible managing employee for a large
company who before me had NO liceneses), have worked for the past 12 yrs
as a machine shop electrician (with no failures to date), CNC repair
tech and so forth.

However..Ive refused to belong to any union since 1974, when my 6 week
stint as a UAW worker left me cold about unions.

Am I just a "handyman" because I dont belong to a union <spit>?

My business cards indicate that I do electrical (non licensed) as well
as CNC and Machine Tool Repair.

So am I simply a "handyman"?

Inquiring minds really want to know.

StickThatInYourPipeAndSmokeIt

unread,
Jul 5, 2009, 6:26:07 PM7/5/09
to
On Sun, 05 Jul 2009 13:44:18 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>
>We must ask you at this point...what is your definition of an
>electrician.

I guarantee it doesn't match yours.

You seem to think that since you understand the rules of making a
connection that you understand electrical power.

I doubt seriously that you have such a grasp of the industry.

James Sweet

unread,
Jul 5, 2009, 6:33:48 PM7/5/09
to
Bruce L. Bergman wrote:
> On Sat, 4 Jul 2009 23:40:18 -0700, John E. <inco...@xbjcd.com>

> wrote:
>
>> I have been asked to offer an opinion in a sensitive situation.
>>
>> A machinist moved his shop across town and required some rewiring (3-phase
>> outlets, conduit, etc.) in order to locate some machines where he wanted
>> them.
>>
>> He hires a guy who's not a pro (and later discovers is not insured) but has
>> done shop wiring before and had a good attitude and track record. The guy
>> does good work. No complaints about the quality of his work.
>>
>> Owner throws the switch, all works fine.
>>
>> The story continues 4 weeks later when the very expensive CNC fries its
>> controller PCB to the tune of $4000.
>>
>> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>> power supply were set for 220.
>>
>> What is the legal and moral responsibility of each party?
>>
>> What will not be helpful are replies about the character or intelligence of
>> either of the players or their actions.
>
> The nominal utility power as supplied is supposed to be 240V. 5
> volts over is a touch hot, but not out of the bounds of normal
> tolerances - turn everything on in the neighborhood some hot August
> afternoon with the AC units cranked, and tell me what the voltage
> reads then...
>
>


That is not always the case. I'm a little rusty when it comes to 3 phase
distribution, but I've dealt with some things like this in a machine
shop friends of mine own. The voltage depends on the service to the
building. Some shops have 208V and some have 240V, and we've had to
reconfigure machines from time to time that were purchased from other
locations, or run some off buck/boost transformers if they were not
configurable. Perhaps someone more knowledgeable can fill in the details.

It's good practice of course to measure the voltage and double check the
configuration of the particular machine prior to applying power.

$4K seems pretty high though, did anyone look into repairing the damaged
board?

James Sweet

unread,
Jul 5, 2009, 6:40:26 PM7/5/09
to

>
> If an unlicensed person does electrical work, the work has to be inspected
> by a licensed electrician before the power is turned on. If that was not the
> case, there would be no point in licensing electricians, would there?
>
> Geoff.


Depends on where you are. Here in the US, the work has to be inspected
by an inspector, not an electrician. You have to be a licensed
electrician to be hired by most electrical contracting companies, but
there is no law against unlicensed people electrical work. I've replaced
electrical service panels and added circuits for renovations in the
homes of quite a few friends and family members, I'm not licensed, but
it was no trouble to get a permit and have the work inspected when it
was complete. Even licensed electricians have to get their work inspected.

James Sweet

unread,
Jul 5, 2009, 6:44:56 PM7/5/09
to
Ignoramus20157 wrote:
> 245 volts is only mildly on the high side and should not cause the
> symptom described.
>
> i
>


As well as sometimes things just do fail. If only I had a dollar for
every time someone with zero technical knowledge told me "this failed
because so and so did this or that". Just because something broke
shortly after work was done, does not automatically mean that the work
done is what caused it to break.

Gunner Asch

unread,
Jul 5, 2009, 6:49:08 PM7/5/09
to
On Sun, 05 Jul 2009 15:26:07 -0700, StickThatInYourPipeAndSmokeIt
<Zarat...@thusspoke.org> wrote:

>On Sun, 05 Jul 2009 13:44:18 -0700, Gunner Asch
><gun...@NOSPAMlightspeed.net> wrote:
>
>>
>>We must ask you at this point...what is your definition of an
>>electrician.
>
> I guarantee it doesn't match yours.
>
> You seem to think that since you understand the rules of making a
>connection that you understand electrical power.

Odd...so Im simply a wire hooker-upper? And my CNC machine repair is
simply making connections? No understanding of the trade?


>
> I doubt seriously that you have such a grasp of the industry.

Why...because Im not a Union Member?

Chuckle...I charge MORE than most Union Members do. And I get the work.

I suggest you review what you wrote..and why you wrote it.

<VBG>

James Sweet

unread,
Jul 5, 2009, 6:50:07 PM7/5/09
to
Jon Danniken wrote:
> William Sommerwerck wrote:
>>> My drier sees 250VAC. Low voltage stuff in this house gets 125VAC.
>>> Everything is working just fine.
>> <sniff> <sniff> Is that burning cotton I smell?
>
> Drier has a temperature limiter, so although the slightly higher voltage
> results in a slightly quicker "turn on" time for the elements, they still
> are shut off at the same temperature regardless of incoming voltage.
>
> Jon
>
>


I rented a house for a while that had unusually high line voltage. It
varied from around 122V to 125V depending on the time of day. If it was
much higher than that, I'd be concerned, but anything from 115V to 125V
is pretty normal.

A friend of mine over in the UK is near the end of a long run from the
transformer that powers his street. His voltage varies considerably,
from as low as 220V to nearly 250V.

Jamie

unread,
Jul 5, 2009, 7:01:17 PM7/5/09
to
John E. wrote:
> I have been asked to offer an opinion in a sensitive situation.
>
> A machinist moved his shop across town and required some rewiring (3-phase
> outlets, conduit, etc.) in order to locate some machines where he wanted
> them.
>
> He hires a guy who's not a pro (and later discovers is not insured) but has
> done shop wiring before and had a good attitude and track record. The guy
> does good work. No complaints about the quality of his work.
>
> Owner throws the switch, all works fine.
>
> The story continues 4 weeks later when the very expensive CNC fries its
> controller PCB to the tune of $4000.
>
> Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
> power supply were set for 220.
>
> What is the legal and moral responsibility of each party?
>
> What will not be helpful are replies about the character or intelligence of
> either of the players or their actions.
>
> Thanks.
Sorry, but that little upward swing didn't cause the issue..

Sounds to me like some one couldn't properly determine the real
problem with the control board and opted to simply replace the whole
thing or, the person doing the work on the repairs caused more damage
them self's and are covering their tracks.

I'm sorry, but 4 weeks into operation and it worked fine all that
time, I think you should look else where for the problem or just simply
eat the coast of a broken down CNC machine.

My guess is the moving process may have caused some sensitive
electronics on the board to get ajar if the CNC was possibly dropped
or whacked hard enough to cause a fracture crack in a solder joint that
finally showed it's oats.

Of course, that is just my opinion. You can take it with a grain of salt.

Ignoramus20157

unread,
Jul 5, 2009, 6:56:15 PM7/5/09
to
On 2009-07-05, John E <inco...@xbjcd.com> wrote:
>> 2. Is it normal for electricians to measure the voltage, and "do something"
>> about it if it's not correct (if only reporting the problem to the
>> businessman)?
>
> This is the basic question I'm asking. Is it common and regular practice to
> inform the owner of a voltage as high as 245? And to suggest that he have
> factory personnel come and look at each machine and examine PS taps and such?
> And if he had hired a licensed electrician would the electrician likely had
> informed the owner of the voltage difference?

I have 245 volts in my garage. Everything works great.

245 volts is a perfectly normal voltage. It corresponds to 122.5 volts
AC from a regular outlet.

There is no causal relationship, as far as I can tell, between
perfectly normal voltage provided in your shop, and your CNC machine
frying after 3 more weeks.

I have not yet seen a more inane discussion thread.

i

john

unread,
Jul 5, 2009, 7:10:07 PM7/5/09
to
Ignoramus20157 wrote:


Dont worry there will be more. Its a great form of mindless intertainment.

Any CNC control or machine that cannot take a 10% overvoltage is a
piece of junk to begin with. Power supply technology in the last 20
years can easily design units that will handle these variations. The
power company likes to hold the voltage on the supply lines as high as
possible to reduce the losses per kw metered and delivered.
I have a number of CNC machines running on 515 volts measured at the
machine internal disconnect and never had a control failure from
overvoltage. Undervoltage is what damages equipment because the
currents run higher for the same work done and the power components get
hotter from the higher current.


John

Tim Williams

unread,
Jul 5, 2009, 7:11:46 PM7/5/09
to
"Ignoramus20157" <ignoram...@NOSPAM.20157.invalid> wrote in message
news:Y4edneEdUJQSsszX...@giganews.com...

> 245 volts is a perfectly normal voltage. It corresponds to 122.5 volts
> AC from a regular outlet.

Oddly enough, that's exactly what I've measured (give or take a few tenths)
in the MSOE power lab (which is equipped with 208V 3 phase), and very nearly
the same at my own bench at home.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

Gunner Asch

unread,
Jul 5, 2009, 7:40:10 PM7/5/09
to
On Sun, 05 Jul 2009 15:33:48 -0700, James Sweet <james...@gmail.com>
wrote:

CNC electronics cost about 4-8 times as much to fix as normal
electronics. Shrug..its called :"the going rate" unfortunately.

Gunner Asch

unread,
Jul 5, 2009, 7:43:44 PM7/5/09
to
On Sun, 05 Jul 2009 19:10:07 -0400, john <amd...@intergrafix.net> wrote:

>>
>> I have not yet seen a more inane discussion thread.
>
>
>Dont worry there will be more. Its a great form of mindless intertainment.
>
>Any CNC control or machine that cannot take a 10% overvoltage is a
>piece of junk to begin with.


As a CNC tech..I agree with you. Unfortunately however...there are far
far too many Big Name manufactures out there who utilize minimal design
perameters when they make something (very expensive) and then charge out
the ass when it goes tits up.

Rich.

unread,
Jul 5, 2009, 7:53:47 PM7/5/09
to

"Gunner Asch" <gun...@NOSPAMlightspeed.net> wrote in message
news:r29255hd4o21ml5ml...@4ax.com...

> On Sun, 5 Jul 2009 21:04:04 +0000 (UTC), "Geoffrey S. Mendelson"
> <g...@mendelson.com> wrote:
>
>
> So then what am I? I passed the tests, at one time held a (California)
> C7 and C10 license, ( as responsible managing employee for a large
> company who before me had NO liceneses), have worked for the past 12 yrs
> as a machine shop electrician (with no failures to date), CNC repair
> tech and so forth.
>
> However..Ive refused to belong to any union since 1974, when my 6 week
> stint as a UAW worker left me cold about unions.
>
> Am I just a "handyman" because I dont belong to a union <spit>?
>
> My business cards indicate that I do electrical (non licensed) as well
> as CNC and Machine Tool Repair.
>
> So am I simply a "handyman"?
>
> Inquiring minds really want to know.
>
> Gunner

Yes, you're a glorified handyman...happy? ;-)

Yes you have the knowledge and experience, but as long as you do not hold a
valid license, you can call yourself an electrician, but you cannot call
yourself a licensed electrician. As an unlicensed electrician you cannot
LEGALLY perform ANY electrical work outside of your own single family
residence. BTW, union or not makes no difference, it's state law we're
talking about.

Rich.

unread,
Jul 5, 2009, 7:54:49 PM7/5/09
to

"James Sweet" <james...@gmail.com> wrote in message
news:h2rabn$d7g$1...@news.eternal-september.org...

>
> Depends on where you are. Here in the US, the work has to be inspected by
> an inspector, not an electrician. You have to be a licensed electrician to
> be hired by most electrical contracting companies, but there is no law
> against unlicensed people electrical work. I've replaced electrical
> service panels and added circuits for renovations in the homes of quite a
> few friends and family members, I'm not licensed, but it was no trouble to
> get a permit and have the work inspected when it was complete. Even
> licensed electricians have to get their work inspected.

You're fooling yourself. You cannot legally do any electrical work at the
homes of your friends or family. If there is ever an electrical fire at any
building that you did electrical work in...you can kiss your life goodbye.
You can be arrested, tried in a criminal court, and sentenced to prison,
plus sued for everything you own in a civil court. This can happen to you
because it is a crime in any state (as far as I know) for you to do this
work. Liability insurance is not even an option for you because you have to
be licensed to get the insurance in the first place.

Jamie

unread,
Jul 5, 2009, 8:07:57 PM7/5/09
to
RoyJ wrote:

>
>>
>> Assuming a nominal 240VAC supply, 245V is in no way "not correct" --
>> it's only about a 2% overvoltage.
>
>
> And since there is likely no load in shop when the install was taking
> place, the 245 would be a higher than normal reading.
>
> But I question the use of "3phase" and "245 volts" in the OP question.
> Around here, 245 volts would be perfectly normal for a single phase
> circuit, very high for a "standard" 208/3 phase delta.
We still use 208 for ligthing only..

Wes

unread,
Jul 5, 2009, 8:00:41 PM7/5/09
to
john <amd...@intergrafix.net> wrote:

>The failure that you had was probably caused by your rigger not using an
>airride trailer to move the equipment and something got shaken up. Four
>weeks of running proves the voltage was not the problem. Some
>disgruntled employee probably pissed in the cabinet.
>
>
> 245 volts is within the normal specs from the utility. AS far as
>changing the tap, you should have called in a machine tech to set it up.
> An electrician wires only to the safety disconnect switch in the
>machine, after that it is your responsibility to call in a machine setup
>tech.

Moving a machine unleases the devils inside. We move a machine a hundred feet across the
plant and we often have issues in the near term. Moving introduces physical shock loads
into the electrics, often causes connectors to lose connection, marginal components to
fail, ect. We moved one machine 200 feet and when we powered it up, I had to reload
parameters and pc parameters.

No mention was made of the age of the machine by the OP. Caps dry out and such. It might
have just been the machines time to go. I still think the shop owner is looking for a
free lunch.

Wes

--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

krw

unread,
Jul 5, 2009, 8:20:40 PM7/5/09
to

That depends entirely on the jurisdiction. Several cities have
tradesmen full employment laws. Some have no inspectors at all.

Jamie

unread,
Jul 5, 2009, 8:45:54 PM7/5/09
to
John Larkin wrote:

> On Sun, 05 Jul 2009 02:58:00 -0400, Spehro Pefhany
> <spef...@interlogDOTyou.knowwhat> wrote:
>
>
>>On Sat, 4 Jul 2009 23:40:18 -0700, the renowned John E.


>><inco...@xbjcd.com> wrote:
>>
>>
>>>I have been asked to offer an opinion in a sensitive situation.
>>>
>>>A machinist moved his shop across town and required some rewiring (3-phase
>>>outlets, conduit, etc.) in order to locate some machines where he wanted
>>>them.
>>>
>>>He hires a guy who's not a pro (and later discovers is not insured) but has
>>>done shop wiring before and had a good attitude and track record. The guy
>>>does good work. No complaints about the quality of his work.
>>>
>>>Owner throws the switch, all works fine.
>>>
>>>The story continues 4 weeks later when the very expensive CNC fries its
>>>controller PCB to the tune of $4000.
>>>
>>>Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>>>power supply were set for 220.
>>>
>>>What is the legal and moral responsibility of each party?
>>>
>>>What will not be helpful are replies about the character or intelligence of
>>>either of the players or their actions.
>>>

>>>Thanks.
>>
>>IMO, 11% high voltage over nominal should not "fry" the controller
>>board in the first place.
>>
>>
>
>

> Yes. The controller was overly fragile, or it may have just had a
> random failure unrelated to supply voltage. That happens.
>
> If the owner blames the electrician, don't use him again. Sue the
> power company for providing 245.
>
>
> John
>
You can only do that if the electric company is actually providing that
245V.
It's possible they are providing 480/460 V 3 Phase, and a in house
transformer is being used. If that is the case, then there should be
taps on the primary side to adjust this how ever, this measurement
must be taken with at least 50% load of the shop on it to get a true
reading.

245V is not uncommon and shouldn't cause any issues, actually,
induction motors run better on peppier voltages.


I may sound like I'm getting fired up over this with multiple reply's
I have made, it's nothing against you John how ever, this comes from
events that I have seen take place at work where expensive electronics
just went faulty on normal use and caused a lot of down time and
material loss. The powers to be that don't know anything about the field
start pointing fingers and when they research to see who was the last one
to have their hands in the machine no matter how long ago it was. They
think its a good justification to start blame storming. Some time people
loss their jobs when they did absolutely nothing wrong only to save the
ass of some one else!.

Doug Miller

unread,
Jul 5, 2009, 8:41:58 PM7/5/09
to
In article <slrnh51oi...@cable.mendelson.com>, g...@mendelson.com wrote:

>Doug Miller wrote:
>> You're missing the point. This has nothing to do with the voltage supplied
>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>> supply (for example) 4KV. A transformer at the point of service reduces that
>> to 220V, or 240V, or whatever. Different transformers connected to the *same*
>> 4KV primary voltage could easily produce different secondary voltages.
>
>No, I'm not. When I lived in the US, (PECO) the electric company sold
>me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>dropped down during times of high usage.
>
>They did not supply or sell me 4kv volts, or anything else.

Yes, I'm afraid you are missing the point. Different locations, even though
attached to the same local grid, may have different supply voltages because
they are receiving those supplies through different transformers.

Doug Miller

unread,
Jul 5, 2009, 8:45:40 PM7/5/09
to
In article <h2qs1...@news3.newsguy.com>, daestrom <daes...@twcny.rr.com> wrote:
>krw wrote:
>> On Sun, 5 Jul 2009 17:29:04 +0000 (UTC), "Geoffrey S. Mendelson"

>> <g...@mendelson.com> wrote:
>>
>>> Doug Miller wrote:
>>>> You're missing the point. This has nothing to do with the voltage supplied
>>>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>>>> supply (for example) 4KV. A transformer at the point of service reduces
> that
>>>> to 220V, or 240V, or whatever. Different transformers connected to the
> *same*
>>>> 4KV primary voltage could easily produce different secondary voltages.
>>> No, I'm not. When I lived in the US, (PECO) the electric company sold
>>> me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>>> dropped down during times of high usage.
>>
>> 240V isn't "two phase", rather single phase, or otherwise known as
>> "split phase". ...and it had better not be 127V (maybe twice that).

>>
>>> They did not supply or sell me 4kv volts, or anything else.
>>
>> They supplied that to the pole. Please read.
>>
>
>What they carry on the pole is immaterial. What they supply to the
>customer service entrance is the 'point of sale'.
>
>Very few homes or light commercial service is in the 4kV range in the
>US.

Nobody ever said it was.

> The service entrance voltage is usually much lower, 240 or 480.

Right, I think we all know that.

>In
>these cases, the step-down transformer used to convert from distribution
>voltage (e.g. 4kV) to the service entrance voltage is the utility's
>responsibility.
>
>The utility is responsible for supplying the voltage/frequency at the
>service entrance / metering point of sale, not 'the pole'.

Exactly so. Anyone who still doesn't understand how different premises
attached to the same local grid could have service entrance voltages which
are *nominally* the same but *actually* different by five or ten percent,
please raise your hand.

Geoffrey S. Mendelson

unread,
Jul 6, 2009, 12:44:03 AM7/6/09
to
Doug Miller wrote:
> Yes, I'm afraid you are missing the point. Different locations, even though
> attached to the same local grid, may have different supply voltages because
> they are receiving those supplies through different transformers.

I got that. What is wrong is that the person who wrote that originally (was
it you?) used that to explain why a regular house outlet could be 220 volts
on one side of town, and 240 volts on another, both connected to the same
"grid".

There's going to be some variation, but not that much.

Michael A. Terrell

unread,
Jul 6, 2009, 1:08:07 AM7/6/09
to

"Geoffrey S. Mendelson" wrote:
>
> Doug Miller wrote:
> > Yes, I'm afraid you are missing the point. Different locations, even though
> > attached to the same local grid, may have different supply voltages because
> > they are receiving those supplies through different transformers.
>
> I got that. What is wrong is that the person who wrote that originally (was
> it you?) used that to explain why a regular house outlet could be 220 volts
> on one side of town, and 240 volts on another, both connected to the same
> "grid".
>
> There's going to be some variation, but not that much.


Nonsense! Do you believe that the entire town is powered by a single
substation, and that there are no I/R losses? It IS possible that an
older part of a town hasn't been upgraded in a long time, and that the
additional load pulls the line voltage down at the end of a MV feed
while another site is closer to a substation and has higher voltage
available to the building.

--
You can't have a sense of humor, if you have no sense!

StickThatInYourPipeAndSmokeIt

unread,
Jul 6, 2009, 1:48:41 AM7/6/09
to
On Sun, 05 Jul 2009 15:16:00 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>On Sun, 5 Jul 2009 21:04:04 +0000 (UTC), "Geoffrey S. Mendelson"
><g...@mendelson.com> wrote:
>
>>Gunner Asch wrote:
>>
>>> We must ask you at this point...what is your definition of an
>>> electrician.
>>
>>Someone who has a license, (and/or) is a member of the union, passed a
>>test that entitles him to call himself an electrician.
>>
>>But not someone with no formal training, licensure or certification.
>>
>>Geoff.
>
>So then what am I? I passed the tests, at one time held a (California)
>C7 and C10 license, ( as responsible managing employee for a large
>company who before me had NO liceneses), have worked for the past 12 yrs
>as a machine shop electrician (with no failures to date), CNC repair
>tech and so forth.
>
> However..Ive refused to belong to any union since 1974, when my 6 week
>stint as a UAW worker left me cold about unions.
>
>Am I just a "handyman" because I dont belong to a union <spit>?
>
>My business cards indicate that I do electrical (non licensed) as well
>as CNC and Machine Tool Repair.
>
>So am I simply a "handyman"?
>
>Inquiring minds really want to know.

You can get a license without being in the union.

Excuses do not make you qualified. Especially if the tests you took
were way back in '74.

Gunner Asch

unread,
Jul 6, 2009, 2:40:47 AM7/6/09
to

Of course I can. And did.


>
> Excuses do not make you qualified. Especially if the tests you took
>were way back in '74.

Where did you get that date from? Was that the year you were spawned?

I put my C7-C10 on "Hold" with the California BCA in 1998. I think its
expired now..as I recall, it only had a 10 yr life on hold.

Shrug..another weekend at a Contractors Fast Learn and take the test on
Monday. Not a big deal. Except the fees and costs.
Which means Ill simply continue on as a CNC tech who occasionally does
electrical work, until the economy turns around. Of course..I may be
near retirement age by that time...assuming the US doesnt melt down
totally.

Shrug

Archimedes' Lever

unread,
Jul 6, 2009, 4:11:46 AM7/6/09
to
On Sun, 05 Jul 2009 16:40:10 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>CNC electronics cost about 4-8 times as much to fix as normal
>electronics. Shrug..its called :"the going rate" unfortunately.

Motor controllers are 70s technology with MAYBE 90s electronics, if you
are lucky. Even if it is a brand new design, it still isn't worth
anything more than any other industrial application.

$4000 is a bit much for a simple swap out.

Perhaps it is guys like you that have inflated the price over the
years. Overt greed is such a sad thing. It produces jerks that thumb
their noses at the entire industrial world, then cannot figure out why
God handed you a heart condition.

I guess that's what they all deserve for buying Japanese CNC hardware.

Buy American. I'll bet that one of Cincinnati Milacron's controller
boards do not cast that much.

Laugh laugh laugh? You say? I laugh at you, jackass.

I say that I hope that chest gripper of death hits you soon, because
you are a major Asch hole.

Martin Brown

unread,
Jul 6, 2009, 4:11:51 AM7/6/09
to
William Sommerwerck wrote:
>>> 1. Did the electrician have any control over the voltage when the system
>>> was rewired?

>
>>> 2. Is it normal for electricians to measure the voltage, and "do
> something"
>>> about it if it's not correct (if only reporting the problem to the
>>> businessman)?
>
>> You missed the point of the original post. The person who did the work was
>> NOT an electrician, they were a "handyman" hired to do the work.
>
> I didn't miss the point (I think). He was doing the work of an electrician.
> And whether or not he was a licensed electrician, he is still morally
> responsible for the quality of his work. (Think Hamurabi.)

Only if it can be shown that he did something wrong. I don't know what
US tolerances on voltage are but in the UK 245v on a nominally 240 line
(these days 230v with asymetric tolerancing) wouldn't raise eyebrows.

>> Since the person never said where they were, it's hard to guess what the
>> rules are but in (almost?) every jurisdiction that licenses
>> electricians, a license is needed to do electrical work.


>
>> If an unlicensed person does electrical work, the work has to be inspected
>> by a licensed electrician before the power is turned on. If that was not
> the
>> case, there would be no point in licensing electricians, would there?
>

> No, there wouldn't be. But if he botched the job, he has to be held
> responsible. Doesn't he?

Iff he botched the job. The kit worked for a while after he left. And he
did not claim to be a qualified electrician.

Had he connected the machine chassis to live and electrocuted someone
then it would be a different matter. But even then the employer who got
in a cut price handyman to do a qualified industrial electricians job
would still be guilty of more serious fundamental health and safety
offences for not having the installation inspected by a competent person
before switching it on. What are the US regs like on employer liability?
>
> Of course, one might argue that if the person who hired him /knew/ he wasn't
> an electrician, and didn't have the work inspected, then he (the hirer) is
> responsible for whatever went wrong.

Exactly. And that is how the insurers would argue it to avoid paying out
a dime if the whole building burnt down as a result of unqualified
electrical work that had not been properly inspected before switch on. I
don't see that the handyman has anything to answer for although he may
still have problems with frivolous litigation from the OP's mate.

Regards,
Martin Brown

StickThatInYourPipeAndSmokeIt

unread,
Jul 6, 2009, 4:15:08 AM7/6/09
to
On Sun, 05 Jul 2009 16:43:44 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>As a CNC tech..I agree with you. Unfortunately however...there are far
>far too many Big Name manufactures out there who utilize minimal design
>perameters when they make something (very expensive) and then charge out
>the ass when it goes tits up.

Yeah, this dopey fuck really knows about quality. NOT!

"Big Name manufacturers"? What easy sleazy Japanesey?

Cite, asswipe? US makers?

Don't jack off at the mouth without backing it up.

What are you pissed about? Single sided boards? What? How fucking
hard can it be to be one that touts hi,mself as a CNC tech if all the
gear is so "cheaply made".

Jeez, when are you going to go tit up?

StickThatInYourPipeAndSmokeIt

unread,
Jul 6, 2009, 4:22:45 AM7/6/09
to
On Sun, 05 Jul 2009 20:00:41 -0400, Wes <clu...@lycos.com> wrote:

> Moving introduces physical shock loads
>into the electrics,

Jeez. Unless it is full of improperly torqued screw type terminations,
there is NOTHING in a simple shock that would damage ANY CNC "electrics"
as you call them.

They can handle like 40Gs, Just like a hard drive can. They can
certainly handle ten, and unless you dropped the fucking thing, you
cannot possibly shock a PWA to that degree.

"Physical shock loads" is a bunch of crap too. They get subjected to
physical shocks, which get transferred across an assembly, but their is
no remnant "load" or anything else. If there is, the entire damned thing
all the way out to the containment case for it is designed wrong.

You would have to drop a machine from a foot in the air to cause a big
enough shock.

I would be hiring new material handling personnel if they were not able
to move a few tons around gracefully enough to keep from damaging any
electronics contained on the load.

Gunner Asch

unread,
Jul 6, 2009, 6:48:34 AM7/6/09
to
On Mon, 06 Jul 2009 01:11:46 -0700, Archimedes' Lever
<OneBi...@InfiniteSeries.Org> wrote:

>On Sun, 05 Jul 2009 16:40:10 -0700, Gunner Asch
><gun...@NOSPAMlightspeed.net> wrote:
>
>>CNC electronics cost about 4-8 times as much to fix as normal
>>electronics. Shrug..its called :"the going rate" unfortunately.
>
> Motor controllers are 70s technology with MAYBE 90s electronics, if you
>are lucky. Even if it is a brand new design, it still isn't worth
>anything more than any other industrial application.
>
> $4000 is a bit much for a simple swap out.

Yes it is indeed. Take that up with the Japanese btw..and their US
agents.


>
> Perhaps it is guys like you that have inflated the price over the
>years. Overt greed is such a sad thing. It produces jerks that thumb
>their noses at the entire industrial world, then cannot figure out why
>God handed you a heart condition.

My greed? Hummm perhaps you havent any idea that Im one of the cheapest
CNC service techs in So. Cal? Or is it simply that Im A service tech
that busts your chops?
Or are you simply an argumentative Leftwing piece of shit who doesnt
like anyone to the Right of Trotsky? Powa to da Pipples!!!


>
> I guess that's what they all deserve for buying Japanese CNC hardware.
>
> Buy American. I'll bet that one of Cincinnati Milacron's controller
>boards do not cast that much.

How much do you care to wager on that? Be specific......I could use a
nice score. But then..it would appear you are a Leftwinger..and you
would lose, whimper and whine, and then steal someone elses money if I
held a gun to your head and made you pay up on your bet.


>
> Laugh laugh laugh? You say? I laugh at you, jackass.

<yawn>


>
> I say that I hope that chest gripper of death hits you soon, because
>you are a major Asch hole.

And I hope you have a nice day too.

Gunner, off to LA to finish taking apart a factory

Gunner Asch

unread,
Jul 6, 2009, 6:53:52 AM7/6/09
to
On Mon, 06 Jul 2009 01:15:08 -0700, StickThatInYourPipeAndSmokeIt
<Zarat...@thusspoke.org> wrote:

>On Sun, 05 Jul 2009 16:43:44 -0700, Gunner Asch
><gun...@NOSPAMlightspeed.net> wrote:
>
>>As a CNC tech..I agree with you. Unfortunately however...there are far
>>far too many Big Name manufactures out there who utilize minimal design
>>perameters when they make something (very expensive) and then charge out
>>the ass when it goes tits up.
>
> Yeah, this dopey fuck really knows about quality. NOT!
>
> "Big Name manufacturers"? What easy sleazy Japanesey?

Mori Seiki, Sharnoa, Toyoda, Mitsubish and so forth.

Now I know you are simply masturbating while typing..as you dont have a
clue that there are any US manufactures left besides Haas and
Fadal....but hey...enjoy yourself and the rest of us can laugh our asses
off at you.


>
> Cite, asswipe? US makers?
>
> Don't jack off at the mouth without backing it up.

Shush..you must missed a stroke.


>
> What are you pissed about? Single sided boards? What? How fucking
>hard can it be to be one that touts hi,mself as a CNC tech if all the
>gear is so "cheaply made".

<VBG>


>
> Jeez, when are you going to go tit up?

Long after Ive had the chance to piss on your grave.

JosephKK

unread,
Jul 6, 2009, 8:14:11 AM7/6/09
to
On Sat, 4 Jul 2009 23:40:18 -0700, John E. <inco...@xbjcd.com>
wrote:

>I have been asked to offer an opinion in a sensitive situation.
>
>A machinist moved his shop across town and required some rewiring (3-phase
>outlets, conduit, etc.) in order to locate some machines where he wanted
>them.
>
>He hires a guy who's not a pro (and later discovers is not insured) but has
>done shop wiring before and had a good attitude and track record. The guy
>does good work. No complaints about the quality of his work.
>
>Owner throws the switch, all works fine.
>
>The story continues 4 weeks later when the very expensive CNC fries its
>controller PCB to the tune of $4000.
>
>Turns out the voltage in the shop was upward of 245 and the taps in the CNC's
>power supply were set for 220.
>
>What is the legal and moral responsibility of each party?
>
>What will not be helpful are replies about the character or intelligence of
>either of the players or their actions.
>
>Thanks.

Since i am not sure where you are at, and you did not mention. In the
US if the shop owner knowingly hired an non-licensed electrician to do
the install, 'e would have to eat the loss. Similar in UK and much of
Europe. The selected tap voltages and delivered line should have been
within normal acceptance range for the controller power supply. As
for why the controller fried that is unclear at this time; causation
from the mains connections has yet to be discussed adequately.

JosephKK

unread,
Jul 6, 2009, 8:48:04 AM7/6/09
to
On Sun, 5 Jul 2009 17:29:04 +0000 (UTC), "Geoffrey S. Mendelson"
<g...@mendelson.com> wrote:

>Doug Miller wrote:
>> You're missing the point. This has nothing to do with the voltage supplied
>> by the utility. The utility doesn't supply 220V or 240V or whatever. They
>> supply (for example) 4KV. A transformer at the point of service reduces that
>> to 220V, or 240V, or whatever. Different transformers connected to the *same*
>> 4KV primary voltage could easily produce different secondary voltages.
>
>No, I'm not. When I lived in the US, (PECO) the electric company sold
>me 240 volt 2 phase electricity. It was nominaly 127 volts, but often
>dropped down during times of high usage.
>

>They did not supply or sell me 4kv volts, or anything else.
>

>Here it's even simpler. Israel electric sells me 230 volts, 50Hz electicity
>and except for just before the power going out it has been that way for 12
>years. When I had a UPS monitoring the voltage, it was never more than
>1 volt +- spec.
>
>Ok, since you insist would anyone out there who gets 4kv from their local
>electric company please raise your hand.
>
>Geoff.

Household feeds and commercial/industrial feeds are not the same
thing. I have seen many modest size office buildings take 480 V
feeds. I have worked on systems that take 12 kV feeds. I know of
electric service customers that take 138 kV feeds. None of these i
mentioned are industrial. You could check out what an aluminum
smelter takes as feed with a search engine.

Archimedes' Lever

unread,
Jul 6, 2009, 9:16:42 AM7/6/09
to
On Mon, 06 Jul 2009 03:48:34 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

> Hummm perhaps you havent any idea that Im one of the cheapest
>CNC service techs in So. Cal?

Bwuahahahahaha! I'll bet your skill set matches your price schedule.
Low and lame.

Hummm? Yeah, you'd probably be better at that.

StickThatInYourPipeAndSmokeIt

unread,
Jul 6, 2009, 9:18:04 AM7/6/09
to
On Mon, 06 Jul 2009 03:53:52 -0700, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>
>Now I know you are simply masturbating while typing..as you dont have a
>clue that there are any US manufactures left besides Haas and
>Fadal....but hey...enjoy yourself and the rest of us can laugh our asses
>off at you.
>>

You're an idiot. There are about three in Cincinnati alone, including
the biggest in the world, the Cincinnati Milacron.

You are only about as dopey as it gets.

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