Monarch 10EE and VFD conversion
Jon Anderson
http://sfbay.craigslist.org/sby/tls/2034511321.html
Generator model, says ready for VFD conversion.
What all is involved in doing this conversion and what is it likely to
cost me assuming I don't have lots of time to shop for bargains on any
needed components?
Will the 10EE cut metric threads native, or does it require transposing
gears? If the latter, how hard is it to locate the required parts?
Anyone here see this lathe in person and know anything about it's
overall condition? The trip down would burn a day for me and I've got
lots of work. Looking for an engine or toolroom lathe and there's a few
on CL that look promising. Might come down to what comes with the most
tooling ready to run. I've always wanted an HLVH, but a 10EE is
something I think I could live with... <G>
Jon
sta...@prolynx.com
> Found a 10EE in the SF Bay Area on Craigslist,http://sfbay.craigslist.org/sby/tls/2034511321.html
If it's an MG setup, that's a DC motor in there, not the 3-phase
needed for a VFD. You'd end up gutting it, finding a 3-phase motor
that would fit, then hooking up a VFD to that. That's if the DC motor
were a complete wreck, they can usually be overhauled reasonably
easily, if needed. If the machine was really cheap and in really good
shape, it might be worth it. Old electromechanical DC motor controls
are usually pretty robust, they don't take an EE degree to fix. No
way to really know that without a personal inspection, though. Unless
it's got a metric leadscrew, it's not going to cut metric without
conversion gearing. Most older US-made lathes don't have metric
leadscrews, at least the ones that weren't exports to start with.
Stan
Jon Anderson
> If it's an MG setup, that's a DC motor in there, not the 3-phase
> needed for a VFD. You'd end up gutting it, finding a 3-phase motor
> that would fit, then hooking up a VFD to that.
Just got off the phone w/seller. All are DC, this one is the generator
type, not the tube type. It came out of the optics lab at Stanford.
There was some speculation from the guy running the lab that the problem
was just a switch, but since nobody knows, it's being sold as a retrofit.
He mentioned two approaches to retrofitting these, one is to do away
with the gearbox and drive the spindle direct, this loses back gear.
The other is to machine some sort of adapter to fit a 3ph motor to the
gearbox. If I were to go for this, I'd prefer the latter and would love
to hear from anyone that's done it. But would like to solicit input on
the two approaches.
I need another project machine like I need a hole in the head, but this
might turn out to be a decent deal...
Jon
Ignoramus3281
Do you think that you would be limited by its very short bed?
I would personally pass.
i
Jim Wilkins
Would a Variac and rectifier be enough?
jsw
Gunner Asch
This may be of interest to you.....
http://www.practicalmachinist.com/vb/monarch-lathes/vfd-conversion-started-187915/
Gunner
"Confiscating wealth from those who have earned it, inherited it,
or got lucky is never going to help 'the poor.' Poverty isn't
caused by some people having more money than others, just as obesity
isn't caused by McDonald's serving super-sized orders of French fries
Poverty, like obesity, is caused by the life choices that dictate
results." - John Tucci,
Gunner Asch
<jande...@comcast.net> wrote:
Btw...Leigh down at MarMachine just took in an absoultely georgious 13"
Clausing Colchester and will be putting it up before long.....Its an
8015 as I recall..and is loaded with everything..including a DRO....
Which in my professional opinion..while not as "cool"..is a superior
lathe.
Gunner, donning his flame proof suit and ceramic armor....
Gunner Asch
Bingo!
Same here.
Hope you got your armor ready Iggy.....
Jon Anderson
> Do you think that you would be limited by its very short bed?
>
> I would personally pass.
Given money and space, I'd really want an HLVH and a 16x60 engine lathe.
Given that I don't have money and space and can only fit one lathe, no
matter what I get, I'm going to be limited.
An HLVH or 10EE won't handle big stuff, a good size engine lathe isn't
going to give me the precision and RPM I often need.
I'm likely to encounter mostly farm type work in Oz, but that's if I
decide to really go into business there. That would call for the engine
lathe. But if I am going to (finally) have my shop just for me and my
hobby tinkering, then I want the tool room lathe.
The issue of greater importance is how long is it going to take me to
get this thing up and running. I do have an Omniturn, but I absolutely
must have a manual lathe available, so even if it's a good deal, if it's
going to take several months to convert, I'd have to pass.
Decisions, decisions...
Jon
Jon Anderson
> Hope you got your armor ready Iggy.....
Oh heck, not going to flame anyone here! I'd REALLY rather have an HLVH,
but a -lot- of people rate the 10EE very highly, and I know in good
running condition they are worth a lot. He's got accessories for it that
would probably cost as much to buy as he's asking for the whole thing.
So it's at least worth considering. I'm thinking the project aspect of
it is going to kill the idea. I'll have enough of a project just moving
things around to get the manual chucker out of the garage and bring in
anything, let alone haul (another) project home.
Hmm, ok, looked at the PM link. Looks like the mods for a gearbox
conversion really call for an engine lathe, which I don't have, and
don't have access to. Not one good enough for this sort of work anyway.
Looks like it's a pass for me.
Now, if that was a low hours HLVH out of a Stanford lab and needed the
vari drive rebuilt, I'd jump on it for $2500..., and wouldn't be asking
questions here that might alert a potential competitive buyer... <G>
Jon
Jon Elson
> On 11/3/2010 7:38 AM, sta...@prolynx.com wrote:
>
>> If it's an MG setup, that's a DC motor in there, not the 3-phase
>> needed for a VFD. You'd end up gutting it, finding a 3-phase motor
>> that would fit, then hooking up a VFD to that.
>
> Just got off the phone w/seller. All are DC, this one is the generator
> type, not the tube type. It came out of the optics lab at Stanford.
> There was some speculation from the guy running the lab that the problem
> was just a switch, but since nobody knows, it's being sold as a retrofit.
close to impossible to get replacements for.
The all electromechanical type is quite a bit simpler. You have two
control systems. One reduces motor field for the high-speed range,
the other regulates the generator field for the lower speed range. Both
are generally just big rheostats in series with the respective field
windings.
Jon
DoN. Nichols
> http://sfbay.craigslist.org/sby/tls/2034511321.html
>
> Generator model, says ready for VFD conversion.
>
> What all is involved in doing this conversion and what is it likely to
> cost me assuming I don't have lots of time to shop for bargains on any
> needed components?
The generator sort of Monarch 10ee has a three phase motor at
the line side, spinning a generator which produces DC of the needed
voltage and current, and then the speed control feeds voltage separately
to the rotor and the field -- first increasing the rotor voltage as the
speed is turned up, then holding it constant and reducing the field
current, resulting in faster and faster spinning.
Later ones use electronics to produce the DC for the spindle
motor -- and some are more difficult to fix because they use tubes which
are rather rare and expensive these days.
The latest have solid state electronics which are also expensive
to fix.
The simple form of conversion mentioned is simply putting a VFD
between the three phase input and the single-phase power line.
A much more complex one involves removing the three phase motor,
generator, and DC motor, and installing a higher horsepower three phase
motor in place of the DC motor. A friend in the local metalworking club
did this -- and had to do a lot of metalworking to come up with a proper
mount for the three phase motor.
Or -- Monarch will do the conversion for you -- for lots of
money. This may be what he is talking about. And if so, it means that
the current motor/generator and DC spindle motor may be bad, thus the
factory conversion is the best bet.
> Will the 10EE cut metric threads native, or does it require transposing
> gears? If the latter, how hard is it to locate the required parts?
The gears and leadscrew produce inch threads normally. I don't
know whether there is a place to put transposition gears or not. (I've
not actually used one to that extreme -- just the old motor-generator
one at work where I never needed to cut metric threads, so I never
opened up the left-hand side of the headstock.
But -- if so -- the threading dial will not work when doing
metric threads (a common problem with any lathe with an inch thread
leadscrew) -- you will have to stop and reverse the lathe spindle to
back up as you wind the tool out of engagement with the workpiece while
in reverse, and then wind it back in as you switch to forward. You
can't release the half-nuts and expect to cut the same thread path on
another pass.
> Anyone here see this lathe in person and know anything about it's
> overall condition? The trip down would burn a day for me and I've got
> lots of work.
A lot greater distance for me. I would have to take two flights
to get there and back in a single day (if I were lucky). :-)
> Looking for an engine or toolroom lathe and there's a few
> on CL that look promising. Might come down to what comes with the most
> tooling ready to run. I've always wanted an HLVH, but a 10EE is
> something I think I could live with... <G>
The 10ee is a very good machine. Even one as old as the
motor/generator style. (But you may have to turn the commutators and
replace badly worn brushes.
Good Luck,
DoN.
--
Remove oil spill source from e-mail
Email: <BPdnic...@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---
DoN. Nichols
> On Nov 3, 11:38 am, sta...@prolynx.com wrote:
>> On Nov 3, 10:09 am, Jon Anderson <janders1...@comcast.net> wrote:
>>
>>
>>
>>
>>
>> > Found a 10EE in the SF Bay Area on Craigslist,http://sfbay.craigslist.org/sby/tls/2034511321.html
>>
>> > Generator model, says ready for VFD conversion.
[ ... ]
>> If it's an MG setup, that's a DC motor in there, not the 3-phase
>> needed for a VFD. You'd end up gutting it, finding a 3-phase motor
>> that would fit, then hooking up a VFD to that. That's if the DC motor
>> were a complete wreck, they can usually be overhauled reasonably
>> easily, if needed. If the machine was really cheap and in really good
>> shape, it might be worth it. Old electromechanical DC motor controls
>> are usually pretty robust, they don't take an EE degree to fix. No
>> way to really know that without a personal inspection, though. Unless
>> it's got a metric leadscrew, it's not going to cut metric without
>> conversion gearing. Most older US-made lathes don't have metric
>> leadscrews, at least the ones that weren't exports to start with.
>>
>> Stan
>
> Would a Variac and rectifier be enough?
Not a single one. I'm not sure what the voltage the motor wants
is, but you need two controls to duplicate what is built into the system
once you have the ability to generate sufficient voltage. (Since the
thing has a three-phase motor turning a generator to produce the needed
DC, there are no bets as to what the voltage is. They may have gone for
low voltage DC or high voltage (each has its own benefits and
drawbacks), but you need two variable voltages -- the one for the
motor's rotor (increased up to a certain maximum speed and then you
start turning down the voltage (and thus the current) applied to the
motor's field to get even higher speeds.
If the motor/generator and the spindle's DC motor are all in
good shape, you can just put a rotary converter on the input instead of
a VFD and use the lathe as it is. But the fact that he is pushing it as
"VFD conversion ready" suggests that there are problems with the
motor-generator or the DC spindle motor.
DoN. Nichols
>
>> If it's an MG setup, that's a DC motor in there, not the 3-phase
>> needed for a VFD. You'd end up gutting it, finding a 3-phase motor
>> that would fit, then hooking up a VFD to that.
>
> Just got off the phone w/seller. All are DC, this one is the generator
> type, not the tube type. It came out of the optics lab at Stanford.
> There was some speculation from the guy running the lab that the problem
> was just a switch, but since nobody knows, it's being sold as a retrofit.
So -- you could luck out and be able to fix it easily to run
from real three phase or a rotary converter, and not need a VFD.
My suspicion is that it is a problem with brushes in the
generator or DC spindle motor.
> He mentioned two approaches to retrofitting these, one is to do away
> with the gearbox and drive the spindle direct, this loses back gear.
> The other is to machine some sort of adapter to fit a 3ph motor to the
> gearbox.
This latter is the approach the friend in the local metalworking
club took. It was not a quick project, but he did a beautiful job.
> If I were to go for this, I'd prefer the latter and would love
> to hear from anyone that's done it. But would like to solicit input on
> the two approaches.
>
> I need another project machine like I need a hole in the head, but this
> might turn out to be a decent deal...
A heavy (but good) decent deal.
Ignoramus3281
separate field and main windings, why can't it be controlled by two
separate DC power supplies?
Karl Townsend
<jande...@comcast.net> wrote:
I have a 10EE. I LOVE THAT LATHE.
I did the VFD mod keeping the backgear box. Its a bit of a pain to
build, sounds like you don't have time. I'd suggest getting a 10 hp.
thee phase motor and 10 hp. VFD. You'd have it running the same day.
Super easy.
I bought a pair of gears from Scott Logan to do metric 47 and 37 IIRC.
You just put them in the threading gear train.
This lathe could be a pretty good deal. Tooling is VERY expensive and
you've getting a lot with this machine. of course, condition is
everything.
I would buy the 10 hp. 3 phase motot used from a local jockey. i get
one that size for $120 at a place where you just stop and pick it up.
Check automation direct for cost of a 10 hp VFD, I'll guess $1K
without looking.
if you do buy it, I'll go into detail.
Karl
Ignoramus3281
you can buy a 10 HP 3 phase motor from me.
Same day pick up.
Baldor 10 HP 1750 RPM 230/460.
i
> Karl
Jon Anderson
> you can buy a 10 HP 3 phase motor from me.
>
> Same day pick up.
Same day I arrive after driving cross country. <BG>
One of Murphy's corollaries,
"Odds are when you find a great deal on something you need or want, it's
far enough away or too expensive to ship to net any savings"
I'm not sure I even have the power available to run a 10hp spindle...
5hp, is no problem, 7.5, probably. 10hp, might need to do some rewiring.
Unless programming the inverter for a second or two of ramp-up would
keep the motor from drawing the usual inrush spike?
Jon
Karl Townsend
>Why 10hp? Is that to insure adequate torque at low RPM with (I assume
>you're talking about) direct drive?
This is how Monarach does it without a back gear. You need a large
motor to have enough torque at low RPM.
Yes, this is direct drive. Just toss everything out in the bottom of
the machine. Put a pulley on the motor and hook up the VFD.
Karl
Karl Townsend
you'll never come close to using 10 Hp. Like you said, give it a
couple seconds to get to speed and you could go pretty small. have one
of the local EEs check me but I'd use 30 amp 240 single phase. Bet 20
amp might work.
karl
Martin Eastburn
torque but slow speed.
Martin
Jon Anderson
> you'll never come close to using 10 Hp. Like you said, give it a
> couple seconds to get to speed and you could go pretty small. have one
> of the local EEs check me but I'd use 30 amp 240 single phase. Bet 20
> amp might work.
Ok, I could do 30 amps. I have 50 amps single phase available in total,
with my rotary phase converter coming off that circuit with 30 fuses in
the disconnect. I know I don't use all that, so wouldn't have much
concern over pulling 25-30 amps for the lathe.
So, is a motor's inrush draw rate for full load, no load, or some
percentage load? This is good stuff to know even if I end up with
something else.
Jon
Ignoramus3281
2 seconds spin up time == no inrush
Brian Lawson
Hey Iggy,
For starter's, why?? What's wrong with the as-designed method of
supplying the DC voltage to the spindle motor rotor and field from the
same source (in this case, an MG set)? Why two?
Probably not that it can't be done, but safety would dictate a lot of
control circuitry so that the motor can't over-speed because of the
loss of field excitation. Bad news on a lathe if it were to happen.
The motor would probably fly apart within a few seconds, but imagine
the chuck and work-piece speeds for that second or so. If you've
never seen it happen, it's hard to imagine.
Take care.
Brian Lawson,
Bothwell, Ontario.
Gunner Asch
wrote:
>
> Or -- Monarch will do the conversion for you -- for lots of
>money. This may be what he is talking about. And if so, it means that
>the current motor/generator and DC spindle motor may be bad, thus the
>factory conversion is the best bet.
Ive been recently told that Monarch is making a new batch of 10EEs, but
all the machines have been spoken for..primarily the US government
And they are selling for $125,000
Gunner
--
Gunner Asch
Just fire up your mill first and let it run, and it adds to the
capacity of the RPC
Richard J Kinch
I don't see why not. That's certainly how the off-the-shelf controllers
operate, with an optional field winding supply.
I don't know about this particular DC motor, but in general DC motors
with separate field windings can be wired in parallel or series and
run off a single power supply, with varying torque-vs-speed
characteristics for those two configurations.
Jon Anderson
> Just fire up your mill first and let it run, and it adds to the
> capacity of the RPC
It's the inrush draw on top of a couple other machines running that I
was concerned about, not RPC capacity. With everything running right
now, I total 9.5hp, but 5hp is the biggest motor, and it starts just
fine off a 3hp RPC. I'd assume a 10hp motor is going to have at least
double the inrush of a 5hp motor.
Jon
Gunner Asch
Im running 7.5 hp Clausing on my 5hp rotary with no issues
Jon Anderson
> Im running 7.5 hp Clausing on my 5hp rotary with no issues
Well again, it's not RPC capacity I'm worried about, it's the inrush
current that concerned me. If I really need a bigger converter, one of
my customers has a 10hp commercial RPC he's offered me for free.
But if it's going to pop the breaker every time I light it off.
Sorta like the air compressor I bought a couple years ago at an estate
sale. Bought and paid for it, and they let me strip the disconnect box
off the wall. I was aghast when I found 60 amp fuses inside! My whole
house only has 100 amp service. But that's the max inrush. It'll pop 20
amp fuses, but has been running 3 years now on 20 amp slo-blow fuses.
Much as I might like to go look and seriously consider it, I've decided
the Monarch is not for me. I need something I can bring in, level out,
plug in, and run...
Jon
DoN. Nichols
It can. All you need is two power supplies of the right voltage
and current. All of that is produced by the generator in the early ones,
and by the electronics in the later ones. Most people don't have
variable power supplies of the proper ratings on hand. (And no, I don't
know what the proper ratings are. :-)
Enjoy,
DoN. Nichols
The 10EE separately varies the rotor and field at different
times to achieve the various speeds. Think two variable resistors
(probably set up as rheostats in the early M/G types, and as
potentiometers in the later electronic types. The rotor is increased
until you reach a maximum voltage -- and then to continue increasing the
speed, the field current is decreased.
The separate variation si why not a single power supply. No
wiring in either parallel or series in this case.
Enjoy,
Ignoramus30154
> On 2010-11-04, Richard J Kinch <ki...@truetex.com> wrote:
>> Ignoramus3281 writes:
>>
>>> Can someone educate me a little bit. If the drive motor is DC, and has
>>> separate field and main windings, why can't it be controlled by two
>>> separate DC power supplies?
>>
>> I don't see why not. That's certainly how the off-the-shelf controllers
>> operate, with an optional field winding supply.
>>
>> I don't know about this particular DC motor, but in general DC motors
>> with separate field windings can be wired in parallel or series and
>> run off a single power supply, with varying torque-vs-speed
>> characteristics for those two configurations.
>
> The 10EE separately varies the rotor and field at different
> times to achieve the various speeds. Think two variable resistors
> (probably set up as rheostats in the early M/G types, and as
> potentiometers in the later electronic types. The rotor is increased
> until you reach a maximum voltage -- and then to continue increasing the
> speed, the field current is decreased.
>
> The separate variation si why not a single power supply. No
> wiring in either parallel or series in this case.
So, then, there is no real need to change to a 3 phase motor and VFD,
all one needs is to make or buy a proper set of power supplies? That
seems far easier than making all those shaft and mount adaptors and
much more straightforward.
I made a power supply for my mill and it was completely trivial. It
was not adjustable or regulated, though, but I do not think that it
needs to be regulated. Adjustability, may be a bit tricky, but not
totally impossible with a multitap transformer or something like
that.
i
Karl Townsend
wrote:
>On 2010-11-03, Ignoramus3281 <ignora...@NOSPAM.3281.invalid> wrote:
>> Can someone educate me a little bit. If the drive motor is DC, and has
>> separate field and main windings, why can't it be controlled by two
>> separate DC power supplies?
>
> It can. All you need is two power supplies of the right voltage
>and current. All of that is produced by the generator in the early ones,
>and by the electronics in the later ones. Most people don't have
>variable power supplies of the proper ratings on hand. (And no, I don't
>know what the proper ratings are. :-)
>
> Enjoy,
> DoN.
I've heard it said they named the Monarch the 10EE because that's how
many EEs it takes to maintain one.
Karl
Richard J Kinch
> The separate variation si why not a single power supply. No
> wiring in either parallel or series in this case.
The speed and torque characteristics may have been varied that way by the
original antique controls, but that doesn't mean it is the only way to run
that motor. One might, for example, apply a fixed field current and have
it act as a permanent magnet motor, which is quite suitable for this type
of application and horsepower. Such a power supply is easy nowadays with
solid state rectifiers, versus when it was all new.
Multi-KW variacs show up on eBay all the time with little buyer interest
(read: cheap). Typically surplus from theater lighting systems.
Jon Elson
lathe chuck on the high-speed range, will really dip your power, if
running off wimpy single-phase power. However, starting the same motor
off a VFD won't make the slightest flicker in the lights. The VFDs have
soft-start, and you can set the start ramp time to your liking.
Even a fraction of a second ramp-up reduces the surge by a huge factor.
Jon
Jon Elson
> On 11/3/2010 5:58 PM, Karl Townsend wrote:
>
>> Yes, this is direct drive. Just toss everything out in the bottom of
>> the machine. Put a pulley on the motor and hook up the VFD.
>
> Monarch parts to sell that might offset the motor and VFD somewhat...
The problem there is you lose the torque that the DC motor could provide
in its lowest range. DC motors generally have a much wider speed-torque
range than induction motors, and the special motor on the EE was
designed to extend that as far as possible. That's how they got away
without having a back gear. If the DC drive can be fixed relatively
easily, I'd do that. If either the motor or generator are shot, then it
would be REALLY expensive to fix, like a rewind. But, that is fairly
unlikely. It is much more likely to be bad brushes, dirty rheostat or
relay contacts or something like that.
Jon
Ignoramus7928
> Starting a 10 Hp motor right off the mains, especially with a heavy
> lathe chuck on the high-speed range, will really dip your power, if
> running off wimpy single-phase power.
I actually measured the starting current of a 10 HP motor.
Mine, starts very nicely from just 180 uF capacitance on one leg (run
caps only).
At the starting moment, the motor draws 120 amps.
> However, starting the same motor off a VFD won't make the slightest
> flicker in the lights. The VFDs have soft-start, and you can set
> the start ramp time to your liking. Even a fraction of a second
> ramp-up reduces the surge by a huge factor.
In fact what VFDs do not have is hard start. So a VFD may not be able
to start the worst loads, like a crusher or a big conveyor. A lathe,
though, is not a hard starting load.
i
DoN. Nichols
> On 2010-11-05, DoN. Nichols <BPdnic...@d-and-d.com> wrote:
[ ... ]
>> The separate variation is why not a single power supply. No
>> wiring in either parallel or series in this case.
>
> So, then, there is no real need to change to a 3 phase motor and VFD,
> all one needs is to make or buy a proper set of power supplies? That
> seems far easier than making all those shaft and mount adaptors and
> much more straightforward.
Assuming that the spindle motor has no problems. You may need
to skim and re-groove the commutator and put in new brushes.
> I made a power supply for my mill and it was completely trivial. It
> was not adjustable or regulated, though, but I do not think that it
> needs to be regulated. Adjustability, may be a bit tricky, but not
> totally impossible with a multitap transformer or something like
> that.
The trick is getting all that to adjust at the right times.
There is a single knob on the lathe which has the two rheostats or pots
on a single shaft, which each have a range during which they do not
change, as the other one changes.
Doing this with switched taps -- or even a pair of Variacs --
gets a bit tricky.
Yes -- you could use the two pots on the single shaft to control
two power supplies -- with the proper control electronics and SCRs or
triacs -- but you are then getting close to the original electronics in
the later models. If you have one of the later models with a dead set
of electronics, this might be the best way to go. But for a M/G
version, I think that making that work as designed is the better
approach.
There is also a mechanical tach in the headstock to tell you the
RPM you are currently using. (The one at work had that dead,
unfortunately, so I never knew the actual speed -- just went for what
felt right. :-)
If the motor and generator still work -- or can be made to work
fairly easily -- it is easier to go that way.
When you come in to use the lathe, you bend over and hit a
button which (IIRC) is near the floor on the tailstock end. You hear
the motor generator spin up, and then it is ready to use. Then all you
have to do is remember to turn it off when you are done.
DoN. Nichols
> DoN. Nichols writes:
>
>> The separate variation si why not a single power supply. No
>> wiring in either parallel or series in this case.
>
> The speed and torque characteristics may have been varied that way by the
> original antique controls, but that doesn't mean it is the only way to run
> that motor. One might, for example, apply a fixed field current and have
> it act as a permanent magnet motor, which is quite suitable for this type
> of application and horsepower. Such a power supply is easy nowadays with
> solid state rectifiers, versus when it was all new.
I think that with a fixed field current, you will either not get
the designed maximum spindle speed -- or you will be applying so much
voltage to the commutator and brushes that you will burn it out fairly
quickly.
> Multi-KW variacs show up on eBay all the time with little buyer interest
> (read: cheap).
Other than shipping cost. :-)
> Typically surplus from theater lighting systems.
Enjoy,
Jon Anderson
> At the starting moment, the motor draws 120 amps.
My whole house only has 100 amps...
The 10EE is no longer being considered. I found a very very nice Siamp
lathe just up the road. It's got a 5hp motor, so I should have no
problems with that. And, it's 50Hz, so no issues with it down under.
It's just a bit more than I can afford at the moment. :(
But... I have seen soft start controls for 3 phase motors. If I run into
issues with any motor with an inrush draw that blows fuses or pops
breakers, these might be a good option?
Question is, do they install between the motor and mains, and work
automatically upon current flow? Or are they used as a switch between
mains and motor? The former is essentially a zero hassle install.
The latter, seems it would require a rewire of the starting switch on
say, a lathe?
Jon
Ignoramus15579
The soft starts require incoming 3 phase and the switch controls the
soft start (soft start itself is the switch for the motor).
i
Jon Anderson
> The soft starts require incoming 3 phase and the switch controls the
> soft start (soft start itself is the switch for the motor).
Hate to showcase my denseness when it comes to stuff like this, but I'm
not clear on your description. Does the soft start require an input
(remote contact closure) to work, or is it a passive inline device that
does it's thing automatically upon current flow?
Thank you,
Jon
Michael A. Terrell
Download and read the manual for a VFD drive. Not all require a
three phase input, either. Some have to be derated for single phase
service.
--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.
Ignoramus15579
>
> Jon Anderson wrote:
>>
>> On 11/6/2010 7:51 AM, Ignoramus15579 wrote:
>>
>> > The soft starts require incoming 3 phase and the switch controls the
>> > soft start (soft start itself is the switch for the motor).
>>
>> Hate to showcase my denseness when it comes to stuff like this, but I'm
>> not clear on your description. Does the soft start require an input
>> (remote contact closure) to work, or is it a passive inline device that
>> does it's thing automatically upon current flow?
>
>
> Download and read the manual for a VFD drive. Not all require a
> three phase input, either. Some have to be derated for single phase
> service.
>
>
Would you have an example of a single phase "soft start"?
i
Joseph Gwinn
Ignoramus3281 <ignora...@NOSPAM.3281.invalid> wrote:
> Can someone educate me a little bit. If the drive motor is DC, and has
> separate field and main windings, why can't it be controlled by two
> separate DC power supplies?
It can. Considering your programmer background, two big remote-control
power supplies with ethernet interfaces driven by a PC. Make that two
very big power supplies. These are commercially available.
The control law is not simple (I bet those two pots on a shaft are full
custom), but would be easy to program. The hard part will be figuring
out the exact control law, unless Morarch put enough details in a patent.
Hmm. Did a little searching using Google Patents (because USPTO search
does not go back far enough).
Monarch does give a lot of detail in their patents. Here are some hits;
there may be more:
2,055,277 "Motor Automatic Lathe", a pure motor-generator setup.
2,546,692 "Control System", with vacuum tubes and a motor-generator set.
2,864,047 "Motor Control System", also with vacuum tubes (some of which
may be thyratrons) and a motor-generator set.
I haven't read these, but they are clearly on point.
To get printable copies, enter the patent numbers at
<http://www.pat2pdf.org>. (You can also use Google Patent, but be aware
that Google sometimes mangles the drawings.)
Joe Gwinn
Michael A. Terrell
Ignoramus15579 wrote:
>
> On 2010-11-06, Michael A. Terrell ?mike.t...@earthlink.net? wrote:
> ?
> ? Jon Anderson wrote:
> ??
> ?? On 11/6/2010 7:51 AM, Ignoramus15579 wrote:
> ??
> ?? ? The soft starts require incoming 3 phase and the switch controls the
> ?? ? soft start (soft start itself is the switch for the motor).
> ??
> ?? Hate to showcase my denseness when it comes to stuff like this, but I'm
> ?? not clear on your description. Does the soft start require an input
> ?? (remote contact closure) to work, or is it a passive inline device that
> ?? does it's thing automatically upon current flow?
> ?
> ?
> ? Download and read the manual for a VFD drive. Not all require a
> ? three phase input, either. Some have to be derated for single phase
> ? service.
> ?
> ?
>
> Would you have an example of a single phase "soft start"?
I'm talking about the input to the VFD. WTF would you have to derate
a VFD drive with a single phase load?
Jon Anderson
> Download and read the manual for a VFD drive. Not all require a
> three phase input, either. Some have to be derated for single phase
> service.
I was asking about a soft start device, which is NOT a VFD, it's used to
reduce inrush current and mechanical shock to whatever the motor is
driving. Not sure exactly where they're used, nor how. I've just seen
them on ebay now and then, so aware they exist.
This question is totally removed from the discussion of getting that
Monarch up and running. Rather, I'm looking at other lathes, some of
which have 10hp spindles. All I would be looking to do is reduce the
startup current.
Yeah, could go see if I can hunt down a manual, just thought I'd ask
here, on the chance someone has used them and knows how they operate.
Jon
Ignoramus15579
A soft start is NOT a VFD. It works completely differently.
http://en.wikipedia.org/wiki/Soft_start
This is basically a SCR operated device that clips the waveforms given
to the motor, at startup.
i
Ignoramus15579
http://en.wikipedia.org/wiki/Soft_start
All soft starts that I know are three phase only.
To soft start a phase converter, the standard way is to use a pony
motor start.
To run three phase machinery from single phase, to get soft start, the
easiest is to get a VFD (which is not a soft start, but has a benefit
of a soft start in addition to other benefits).
i
Jon Anderson
> To run three phase machinery from single phase, to get soft start, the
> easiest is to get a VFD (which is not a soft start, but has a benefit
> of a soft start in addition to other benefits).
Looking into using a soft start with 3 phase input to a 3 phase motor,
-just- to reduce starting inrush IF I decide I really want a lathe with
a 10hp motor. If it'll do what I want, it makes a 10hp lathe doable,
otherwise I'll have to stay at 5hp or less.
Any discussion of a VFD has nothing to do with the situation I'm looking
at. Maybe I'll just see if I can hunt down a manual online.
Thanks,
Jon
Jon Anderson
that not only do they require external switching to engage, but at least
the ones at Automation Direct require 24v power. And, for what they
cost, at least in the lower HP ratings, I might as well go with a VFD
for the additional benefits provided....
Jon
Michael A. Terrell
> ??
> ?? On 2010-11-06, Michael A. Terrell ?mike.t...@earthlink.net? wrote:
> ?? ?
> ?? ? Jon Anderson wrote:
> ?? ??
> ?? ?? On 11/6/2010 7:51 AM, Ignoramus15579 wrote:
> ?? ??
> ?? ?? ? The soft starts require incoming 3 phase and the switch controls the
> ?? ??
> ?? ?? Hate to showcase my denseness when it comes to stuff like this, but I'm
> ?? ?? (remote contact closure) to work, or is it a passive inline device that
> ?? ?? does it's thing automatically upon current flow?
> ?? ?
> ?? ?
> ?? ? Download and read the manual for a VFD drive. Not all require a
> ?? ? three phase input, either. Some have to be derated for single phase
> ?? ? service.
> ?? ?
> ?? ?
> ??
> ?? Would you have an example of a single phase "soft start"?
> ?
> ?
> ? I'm talking about the input to the VFD. WTF would you have to derate
> ?
> ?
>
> A soft start is NOT a VFD. It works completely differently.
>
> http://en.wikipedia.org/wiki/Soft_start
>
> This is basically a SCR operated device that clips the waveforms given
> to the motor, at startup.
Soft start is a function, not a device.
Michael A. Terrell
Jon Anderson wrote:
>
> On 11/6/2010 10:29 AM, Michael A. Terrell wrote:
>
> ? three phase input, either. Some have to be derated for single phase
> ? service.
>
> I was asking about a soft start device, which is NOT a VFD, it's used to
> reduce inrush current and mechanical shock to whatever the motor is
> driving. Not sure exactly where they're used, nor how. I've just seen
> them on ebay now and then, so aware they exist.
Soft start is a function of the VFD. Otherwise it would blow the
semiconductors the first time it applied power to the motor.
> This question is totally removed from the discussion of getting that
> Monarch up and running. Rather, I'm looking at other lathes, some of
> which have 10hp spindles. All I would be looking to do is reduce the
> startup current.
>
> Yeah, could go see if I can hunt down a manual, just thought I'd ask
> here, on the chance someone has used them and knows how they operate.
I suggested the manual, because you'll have more questions, and the
manual describes how the entire system works so it's easier to grasp the
basics. :)
John
> Can someone educate me a little bit. If the drive motor is DC, and has
> separate field and main windings, why can't it be controlled by two
> separate DC power supplies?
D C motor drives are available to drive both PM and field wound motors.
They are designed with current sensing to shut down for field loss
condition. The Allen Bradley 1336 series is one such drive. Fincor is
another. I would not screw with the DC motor unless it needed new
brushes or some other minor maintenance. Unless you are operating the
machine 24/7 the brushes will last a very long time. It is a very minor
project to install a D C drive. The hardest thing is to add a tach
generator for better speed control if the motor doesn't already have one.
John
John
Brian Lawson
wrote:
>Ignoramus3281 wrote:
>> Can someone educate me a little bit. If the drive motor is DC, and has
>> separate field and main windings, why can't it be controlled by two
>> separate DC power supplies?
>
Hey Iggy,
As I wrote previously, the peril with using two separate sources is in
losing the source for the field winding . If the current supplied for
the armature is available, the motor will literally overspeed to
destruction. Kirchoff's Law will apply. Immediately!!!!
<http://en.wikipedia.org/wiki/Kirchhoff's_circuit_laws>
Now, that usually won't quite happen, as there is normally a current
sensing gadget, like a dash-pot overload, a fast circuit-breaker, or
fast-acting fuse (not a Type D) in the armature circuit, which will
quickly remove the armature source. But for the stated use, that
being the spindle, chuck, and work piece in the lathe, you will be
amazed at how many RPM's that motor can speed up in even 1/2 second,
and the possibility of injury and/or damage is a real risk.
Using the SAME source for both is the simplest of safety
responsibilities. The field should be hard-wired to provide a minimum
current. Opposite to the logical, the motor is SLOWED by INCREASING
the field voltage, or decreasing the armature voltage.
Normal operation would see a constant voltage applied to the field
windings, and controlled changing applied voltage to the armature.
The field voltage is always applied first, and then as the voltage to
the armature is increased you will begin rotation and the rotor will
speed up to some controlled RPM. At the point of maximum voltage
applied to the armature, and where a further increase in RPM is
required, then the field voltage is reduced by some limited amount,
and the RPM will go up, but the current to the field must have that
minimum amount mentioned earlier HARD-WIRED in. Any reversing of the
motor is done ONLY by changing the polarity to the armature.
There are lots of refinements, but this is a simple reason for NOT
using two sources
Good luck.
Take care.
Brian Lawson,
Bothwell, Ontario.
Brian Lawson
<jande...@comcast.net> wrote:
SNIP
>I was asking about a soft start device, which is NOT a VFD, it's used to
>reduce inrush current and mechanical shock to whatever the motor is
>driving. Not sure exactly where they're used, nor how. I've just seen
>them on ebay now and then, so aware they exist.
SNIP
>Jon
Hey Jon,
Soft-Start is very common on hydraulic elevators, especially if the
elevator is of any size. It helps extend the motor life, and reduces
pulley wear and belt wear of the multi -Vbelts (some are direct drive
pumps and don't have the V-belts). But for the owner/customer, it
REALLY cuts down on "dimming the lights" in the building. The only
instant load on the motor at start-up is the motor itself and the
screws in the pump, which is unloaded for at least a few seconds.
There is some use of SoftStart on large MG sets, but in general the MG
sets are going the way of the Dodo-bird and being replaced on new
installations with V.V.V.F. (Variable Voltage-Variable Frequency )
control and use new style AC motors designed for the duty. "Standard"
AC motors are not able to handle VVVF, due to tremendous harmonic
problems. I don't know if the same sort of problems are the reason
that some common use AC motors today are noted as being designed for
VVF use. I really suspect that has more to do with heating than
harmonics.
Dave H.
"John" wrote...
>
> D C motor drives are available to drive both PM and field wound motors.
> They are designed with current sensing to shut down for field loss
> condition. The Allen Bradley 1336 series is one such drive. Fincor is
> another. I would not screw with the DC motor unless it needed new brushes
> or some other minor maintenance. Unless you are operating the machine
> 24/7 the brushes will last a very long time. It is a very minor project to
> install a D C drive. The hardest thing is to add a tach generator for
> better speed control if the motor doesn't already have one.
>
Not to hijack the thread, but does anyone have or know where I can get a
service / repair manual or schematic for the ABB ACS-301-4P9-3 VFD? I have
it up and working (spins the drive, speed control and fwd/rev work) but DHL
managed to drop it (from quite a height) in transit and there's no DC to the
control/programming panel so I can't get in and set the various motor and
braking parameters... The control board (not the programming panel, the top
board in the main unit) is all surface-mount and multi-layer, and is going
to be a sod to trace, although no so hard to add a few repair jumper-wires
if I can find what's broken and where.
I've tried ABB's UK distributors, their answer was "we don't keep
spares/manuals/schematics for anything that old so buy a new one"!
I'd rather not, as it's oldish and so has been easily hacked to fool it into
thinking it has 415V in and thus it can run the Difficult Motor in my
Holbrook (England's Monarch?) C13 (415v only, 3-phase, 3 sets of windings
for the 3 speeds) and, of course, I'm cheap ;)
Thanks all,
Dave H.
--
(The engineer formerly known as Homeless)
"Rules are for the obedience of fools, and the guidance of wise men" -
Douglas Bader
Ignoramus26353
John, then it would seem that a drive like that, in a 10EE monarch,
should be more or less perfect for the job? Am I wrong?
i
John
Yup, all you need to do is add a tach generator so you have better
speed control even though it would work without the tach. All the field
generating ckts are in the drive. The most critical is field loss
detection. Brush type DC motors are not that maintenance intensive.
you check the brushes once in a while and replace when necessary,blow
out the carbon, usually with about five years of continuous use.
As far as alignment, you only have to set the field current as stamped
on the motor and set the crossover at the base speed of the motor as
stamped on the motor tag the crossover being when the armature current
is at the max and the field current is reduced to further increase the
speed of the motor.
John