My Powermaticdrill press with VFD
Greg O
chips with it today.
http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFDmounted.jpg
http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFD.jpg
--
Greg O
Ignoramus15449
Looks way cool. Where is the switch, though?
i
Greg O
"Ignoramus15449" <ignoram...@NOSPAM.15449.invalid> wrote in message
news:W6KdnaXPytjgD7jW...@giganews.com...
Switch? Switch for what?
I got it set up to run it all through the VFD, and axed the factory on-off
switch. I have forward/reverse, jog, start, and stop. I have the braking set
to one second, which is the lowest setting, so at any speed it will come to
a complete stop in one second, or less. When running the VFD at 30 hertz,
and the variable speed cranked all the way down, about 60 RPM, the spindle
will stop in 1/2 a revolution.
What more do you need?
Greg
co_f...@yahoo.com
> Pics with the VFD mounted, and all up and running. I actually produced some
> chips with it today.
>
>
> http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFD...
>
> --
> Greg O
The bins to the left in the picture are empty. What kind of a
metalworker has empty bins?
Paul
Bill McKee
"Greg O" <goo...@hotmail.com> wrote in message
news:P4gVm.343843$Xw3.1...@en-nntp-04.dc1.easynews.com...
Kool. I mistread it as Problematic drill press. ;>)
Greg O
"pdr...@coinet.com" <co_f...@yahoo.com> wrote in message
news:3eb58c0e-6eec-43a5...@y32g2000prd.googlegroups.com...
Bolt bins, and they are not empty. They are just not real full, just full
enough!
Greg O
Steve W.
Nice set-up, seems to be missing the OH-SH(T button though. The one that
you can mash when things go wrong and stop it NOW.
--
Steve W.
Greg O
"Steve W." <csr...@NOTyahoo.com> wrote in message
news:hg6e13$g0k$1...@aioe.org...
The stop button stops the spindle in one second. Fastest braking this VFD
will do.
Good enough "oh shit" button for me.
Greg O
Bill Noble
it for 1 sec on a donward RPM slope - you want the E-stop to cut power to
the motor - every VFD I've ever seen (a few dozen that I've looked at
carefully) had a feature that put it into "neutral" - sometimes you had to
choose but it is always there. Set the "off" switch to "coast" rather than
the decl profile - much safer.
Note that you can have surprises due to too fast decl, such as a screw
mounted thing unscrewing - coast is a much better choice
"Greg O" <goo...@hotmail.com> wrote in message
news:gHDVm.377336$sz1....@en-nntp-10.dc1.easynews.com...
Ignoramus18922
> no - that 1 sec "braking" is really a deceleration profile that will power
> it for 1 sec on a donward RPM slope - you want the E-stop to cut power to
> the motor - every VFD I've ever seen (a few dozen that I've looked at
> carefully) had a feature that put it into "neutral" - sometimes you had to
> choose but it is always there. Set the "off" switch to "coast" rather than
> the decl profile - much safer.
>
> Note that you can have surprises due to too fast decl, such as a screw
> mounted thing unscrewing - coast is a much better choice
You obviously have not tried elecronic deceleration. It may be the
best feature of a VFD on a drill press and other machines.
i
Greg O
"Bill Noble" <nob...@nowhere.invalid> wrote in message
news:hg97nc$k19$1...@news.eternal-september.org...
> no - that 1 sec "braking" is really a deceleration profile that will power
> it for 1 sec on a donward RPM slope - you want the E-stop to cut power to
> the motor - every VFD I've ever seen (a few dozen that I've looked at
> carefully) had a feature that put it into "neutral" - sometimes you had to
> choose but it is always there. Set the "off" switch to "coast" rather
> than the decl profile - much safer.
>
> Note that you can have surprises due to too fast decl, such as a screw
> mounted thing unscrewing - coast is a much better choice
>
>
Stopping too fast on a drill press?? Never heard of such a concept! I would
rather stop right now, than coast to a stop when something goes to hell!
And what is this screw mounted thing you talk of??
Greg O
Gunner Asch
I concure. There are some issues with power stop and coasting..but
frankly..they are less in number and severity when using power stop.
Gunner
"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.
This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost
Greg O
"Gunner Asch" <gun...@lightspeed.net> wrote in message
news:fnvoi5t7k8o8h30h7...@4ax.com...
>>
>>On 2009-12-15, Bill Noble <nob...@nowhere.invalid> wrote:
>>> no - that 1 sec "braking" is really a deceleration profile that will
>>> power
>>> it for 1 sec on a donward RPM slope - you want the E-stop to cut power
>>> to
>>> the motor - every VFD I've ever seen (a few dozen that I've looked at
>>> carefully) had a feature that put it into "neutral" - sometimes you had
>>> to
>>> choose but it is always there. Set the "off" switch to "coast" rather
>>> than
>>> the decl profile - much safer.
>>>
>>> Note that you can have surprises due to too fast decl, such as a screw
>>> mounted thing unscrewing - coast is a much better choice
>>
>>You obviously have not tried elecronic deceleration. It may be the
>>best feature of a VFD on a drill press and other machines.
>>
>>i
>
>
> I concure. There are some issues with power stop and coasting..but
> frankly..they are less in number and severity when using power stop.
>
>
> Gunner
I worked at a machine shop for a few years and I can not think of one time,
when things went wrong, that you wanted the machine to coast to a stop.
Sooner the better when parts are crashing together or flying apart!
I remember years ago watching a couple guys using a drill press. The vise
came loose from the clamp, and next thing you know the drll vise starts
spinning at 500 RPM. The one guy hits the switch, and the guy running the
feed panics and drops the handle, and off course the tooling came loose from
the part, and now you have a drill vise/projectile fly across the room.
Luckily it flew 10 -15 feet from the drill press and did not hit anything or
anyone on the trip. This is a good example where braking to a stop would be
preferred.
Greg O
Bill Noble
"Greg O" <goo...@hotmail.com> wrote in message
news:Od9Xm.397727$BL3.1...@en-nntp-08.dc1.easynews.com...
so, should I tell you about having a heavy blank unscrew from a wood lathe
when the decel was set too high? you can set your stuff any way you want, I
posted how I set my stuff, and why. I, for the information of whomever said
I had never used "tried electronic deceleration", certainly have done so, on
both a wood and on a metal lathe, and have turned it off on both, because of
negative results.
Greg O
"Bill Noble" <nob...@nowhere.invalid> wrote in message
>
>
> >
>
> so, should I tell you about having a heavy blank unscrew from a wood lathe
> when the decel was set too high? you can set your stuff any way you want,
> I posted how I set my stuff, and why. I, for the information of whomever
> said I had never used "tried electronic deceleration", certainly have done
> so, on both a wood and on a metal lathe, and have turned it off on both,
> because of negative results.
No arguement over that one, Each machine/situation may need differant
emergency stops setings. Personally, I have never run a machine with a
screwed on face plate or chuck. The only lathes I have run had cam locks,
and reversing motors so quick stops were not an issue.
Going back to the drill press, I see abssolutely no reason not to stop it
quickly, which is where the topic started!
Greg O
Bill Noble
"Greg O" <goo...@hotmail.com> wrote in message
news:J0cXm.369316$8m4.3...@en-nntp-07.dc1.easynews.com...
Greg - here is why it's a bad idea on a drill press - let's suppose you are
drilling away and the bit jams - it doesn't break the bit and it's pulling
on whatever you were drilling (I don't' know about you, but this does happen
to me from time to time) - if I set the stop to "coast", when I hit stop the
force stops immediately. If I set stop to "decelerate", the force continues
for the length of the deceleration time. I prefer the former.
Gunner Asch
Thats why you set the machinery in your shop the way you wish.
As for me...whenever I use a VFD...it will have a ramp up and a ramp
down time..and the ramp down time will be just about as fast as I can
get it.
This includes the VFD run OmniTurn CNC lathes that I install and
service..that have the ramp down times set to under 2 seconds where
possible...direct from the factory.
Now Id be happy as hell to sell you one...got a nice used one mounted on
a Hardinge HC bed..only $9k..and Ill turn off the VFD braking function
for you when I set it up.
I take checks, cash, money orders, paypal and so forth. Just let me
know when you wish to have it delivered and voila! It will be there.
Greg O
"Bill Noble" <nob...@nowhere.invalid> wrote in message
I have the braking set at one second, the lowest setting, but on this VFD it
seems that it will stop sooner, depending on the load, and RPM. At low RPM,
and low spindle speed on the variable it stops in way less than one second.
At 30 Hertz, about 60 RPM, and low speed it will stop in 1/2 a revolution,
or about 1/2 second. At higher speeds even on coast to stop you have inertia
to be concerned about. The way this machine reacts I believe if the tool is
jammed and the motor or spindle stalled the braking would be instant. Keep
in mind on most VFDs, if the motor is stalled, the braking time is zero, the
VFD will not continue to apply power to a stalled motor after the stop
button is pushed because the VFD sees that the motor is stopped. I guess I
don't worry much either way as my reaction time is slow enough that what
ever carnage that results from a problem will most likely be way over before
I can hit the stop button any way!
Greg O
Gunner Asch
Bill..the fact of the matter is...if you hang a bit, with coast or with
Stop..you are likely to bust the bit no matter what, if its too small
for the mass of the spindle.
Shrug..there it is...
GeoLane at PTD dot NET
<gun...@lightspeed.net> wrote:
>As for me...whenever I use a VFD...it will have a ramp up and a ramp
>down time..and the ramp down time will be just about as fast as I can
>get it.
I can set the VFD I use for my Bridgeport to stop in 1 second. Would
it be hard on the VFD to come to a quick stop like that? Sould you
have an external add-on resistor if you're going to be doing that? My
VFD is rated at 3 HP and the motor is 2 HP.
RWL
Gunner Asch
It really SHOULD have an external resistor. Its a slush pond that all
the nasty stuff gets sent to when you slam on the brakes. And if you
brake to a stop a lot..it really needs to be what the manual calls for,
given some margin for farting around with surplus goodies.
If you can find something appropriate..you really should install it.
The BP spindle is a fairly massive group of steel chunks and needs a
braking resistor to stop it quickly.
A good wirewound works pretty well, and is adjustable...and are often
damned cheap.
Joseph Gwinn
Gunner Asch <gun...@lightspeed.net> wrote:
> On Sat, 19 Dec 2009 23:34:47 -0500, GeoLane at PTD dot NET <GeoLane at
> PTD dot NET> wrote:
>
> >On Sat, 19 Dec 2009 15:27:15 -0800, Gunner Asch
> ><gun...@lightspeed.net> wrote:
> >
> >>As for me...whenever I use a VFD...it will have a ramp up and a ramp
> >>down time..and the ramp down time will be just about as fast as I can
> >>get it.
> >
> >I can set the VFD I use for my Bridgeport to stop in 1 second. Would
> >it be hard on the VFD to come to a quick stop like that? Sould you
> >have an external add-on resistor if you're going to be doing that? My
> >VFD is rated at 3 HP and the motor is 2 HP.
> >
> >RWL
>
>
> It really SHOULD have an external resistor. Its a slush pond that all
> the nasty stuff gets sent to when you slam on the brakes. And if you
> brake to a stop a lot..it really needs to be what the manual calls for,
> given some margin for farting around with surplus goodies.
>
> If you can find something appropriate..you really should install it.
> The BP spindle is a fairly massive group of steel chunks and needs a
> braking resistor to stop it quickly.
>
> A good wirewound works pretty well, and is adjustable...and are often
> damned cheap.
Yes. However, if you use a wirewound resistor not intended as a braking
resistor, there are a few things to ensure:
1. If the open-tube vitrified type (which is what adjustable units
usually are), the resistor must be mounted in a grounded metal enclosure
such that no fire will result should the resistor achieve red heat.
This can happen, and will not damage an open-tube vitrified wirewound
resistor if it doesn't happen too often. Be sure to use heater wire to
connect to the resistor. Unless the resistor is too large for such
overheating to occur.
2. The resistor mounting enclosure must prevent accidental contact with
the terminals, as their normal voltage is around 350 volts DC.
3. Entry of and shorting by metal chips must be prevented. Mounting up
high helps a lot.
4. The resistor must be physically large enough to absorb the stored
energy of all that rotating metal without burnout, as no real heat
dissipation can occur over the one-second stopping time. The energy
from stopping is stored in the resistor as heat, which is only later and
slowly transferred to the atmosphere.
For metalworkers, none of this is hard to do, but I wanted to be sure
that the issues are understood. The easiest option is probably a large
aluminum-clad boltdown power resistor. These are available on the
surplus market for small dollars, as are the big open-tube vitrified
units.
Joe Gwinn
Bill Noble
">> Greg - here is why it's a bad idea on a drill press - let's suppose you
>> are drilling away and the bit jams - it doesn't break the bit and it's
>> pulling on whatever you were drilling (I don't' know about you, but this
>> does happen to me from time to time) - if I set the stop to "coast", when
>> I hit stop the force stops immediately. If I set stop to "decelerate",
>> the force continues for the length of the deceleration time. I prefer
>> the former.
>
> I have the braking set at one second, the lowest setting, but on this VFD
> it seems that it will stop sooner, depending on the load, and RPM. At low
> RPM, and low spindle speed on the variable it stops in way less than one
> second. At 30 Hertz, about 60 RPM, and low speed it will stop in 1/2 a
> revolution, or about 1/2 second. At higher speeds even on coast to stop
> you have inertia to be concerned about. The way this machine reacts I
> believe if the tool is jammed and the motor or spindle stalled the braking
> would be instant. Keep in mind on most VFDs, if the motor is stalled, the
> braking time is zero, the VFD will not continue to apply power to a
> stalled motor after the stop button is pushed because the VFD sees that
> the motor is stopped. I guess I don't worry much either way as my reaction
> time is slow enough that what ever carnage that results from a problem
> will most likely be way over before I can hit the stop button any way!
> Greg O
the characteristic you report is apparently dependent on the VFD - on the
Eurotherm drive on my wood lathe, for example, it will power for the entire
ramp down time even if stalled. So, I guess the final answer is "it
depends"
Gunner Asch
wrote:
Very well stated Joe. I tend to simplify things perhaps too much for
some readers.
GeoLane at PTD dot NET
My Teco VFD specifies a 70 Ohm, 200 Watt braking resistor. I did
some quick looking on eBay and Mouser. It looks like the least
expensive ones are the open tube ones - BUT at around $33 and up. Is
there a less expensive place to buy these or a different way to search
either site that would bring up the less expensive alternatives?
RWL
Bill Noble
series
<GeoLane at PTD dot NET> wrote in message
news:bivti5llebj0qqc00...@4ax.com...
David Lesher
Think suplus places as well. You can use multiple resistors if
you don't mind the simple math.
--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
Gunner Asch
One can get away with a 100 watt tubular or solid resistor if you are
simply operating it HSM and not doing rapid starts and stops ie CNC.
Surplus houses often have similar resistors btw....google is your
friend.
Such as this page....time to find it less than 1 minute...
http://www.surplussales.com/resistors/WireWound/WW70-110.html
DoN. Nichols
>
> "Bill Noble" <nob...@nowhere.invalid> wrote in message
> news:hgjl3h$f0h$1...@news.eternal-september.org...
[ ... ]
>> Greg - here is why it's a bad idea on a drill press - let's suppose you
>> are drilling away and the bit jams - it doesn't break the bit and it's
>> pulling on whatever you were drilling (I don't' know about you, but this
>> does happen to me from time to time) - if I set the stop to "coast", when
>> I hit stop the force stops immediately. If I set stop to "decelerate",
>> the force continues for the length of the deceleration time. I prefer the
>> former.
>
> I have the braking set at one second, the lowest setting, but on this VFD it
> seems that it will stop sooner, depending on the load, and RPM. At low RPM,
> and low spindle speed on the variable it stops in way less than one second.
> At 30 Hertz, about 60 RPM, and low speed it will stop in 1/2 a revolution,
> or about 1/2 second. At higher speeds even on coast to stop you have inertia
> to be concerned about. The way this machine reacts I believe if the tool is
> jammed and the motor or spindle stalled the braking would be instant. Keep
> in mind on most VFDs, if the motor is stalled, the braking time is zero, the
> VFD will not continue to apply power to a stalled motor after the stop
> button is pushed because the VFD sees that the motor is stopped. I guess I
> don't worry much either way as my reaction time is slow enough that what
> ever carnage that results from a problem will most likely be way over before
> I can hit the stop button any way!
I have a three-phase motor which I plan to add to my 12x24"
Clausing lathe (currently has a single-phase motor), and since it has a
L-00 spindle, I consider having both stops to be better. A normal stop
with the deceleration set in the VFD (to whatever works with the most
massive chuck, a reasonable size workpiece, and the highest spindle
speed without tripping the limits on the VFD.) But when things are
really going bad, the motor which I am installing has an electrically
operated brake (actually, the brake is released by power, not actuated
by it), so I will set up the emergency stop switch to drop power from
the input to the VFD and to the brake so the motor and spindle will stop
in the shortest possible time.
FWIW The motor originally was the spindle motor on one of the big
washing-machine style disk drives from mainframe computer
centers. I got it at a hamfest.
Enjoy,
DoN.
--
Email: <dnic...@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 ---
Bill Noble
"David Lesher" <wb8...@panix.com> wrote in message
news:hgn0ms$lit$1...@reader1.panix.com...
pent...@yahoo.com
<nob...@nowhere.invalid> wrote:
>note also that you can use a light bulb
>
>"David Lesher" <wb8...@panix.com> wrote in message
>news:hgn0ms$lit$1...@reader1.panix.com...
>> GeoLane at PTD dot NET <GeoLane at PTD dot NET> writes:
>>
>>
>>>My Teco VFD specifies a 70 Ohm, 200 Watt braking resistor. I did
>>>some quick looking on eBay and Mouser. It looks like the least
>>>expensive ones are the open tube ones - BUT at around $33 and up. Is
>>>there a less expensive place to buy these or a different way to search
>>>either site that would bring up the less expensive alternatives?
Do NOT use a light bulb. The cold resistance of a light bulb can
be less than 1/6th of its nominal hot resistance and this much
lower resistance overloads the VFD braking circuit.
Jim
Ned Simmons
Try it without the resistor first. In my experience it's pretty tough
to trip a VFD decelerating a Bridgeport spindle in any reasonable
time. I have my mill set to 1s accel and decel and have never tripped
it. This is with an older Mitsubishi drive which does have a small
internal resistor, with provision to add more capacity externally.
Similar experience with my previous mill and a different Mitsu VFD.
If your drive has the ability to display the DC bus voltage (a common
feature) you can get an idea how close you are to tripping on
overvoltage before you spend time and money installing a resistor.
I recently built a machine that includes a 5HP gearmotor lifting and
lowering a 2000+ pound load at up to 12 in/s. My customer built the
controls and I was concerned that they were not installing an external
braking resistor on the little AB Powerflex VFD. Very bad things will
happen if the drive trips. We tested the thing extensively and were
not able to trip the drive.
--
Ned Simmons
Lloyd E. Sponenburgh
PTD dot NET> wrote:
>
>
>My Teco VFD specifies a 70 Ohm, 200 Watt braking resistor. I did
>some quick looking on eBay and Mouser. It looks like the least
>expensive ones are the open tube ones - BUT at around $33 and up. Is
>there a less expensive place to buy these or a different way to search
>either site that would bring up the less expensive alternatives?
>
A couple of 250W incandescent bulbs in series will work, having a cold
resistance of about 10ohms, and a hot resistance of about 100 ohms.
They'll heat up to incandescence almost instantly (in just a couple of
cycles).
OTOH, there'll be a 100ms or so of very dramatic braking before the
filaments heat; maybe more than the VFD's output transistors can take --
dunno. Most will handle it just fine, but might trip on overcurrent.
$33/resistor isn't all that expensive, if you need more braking than the
VFD will provide without them.
LLoyd
Gunner Asch
Indeed!!!
Martin H. Eastburn
I have two smooth sided resistors - each 8 ohm (nice speaker loads)
but must be 1000 watt. I'd have to look. I also have a 1/2 ohm IIRC
corn cob. Nice to measure current flow in a circuit - voltage drop.
$33 isn't bad for that - I'm surprised myself.
If you get one, look for mounting hardware. It helps. Or you make some.
Martin
GeoLane at PTD dot NET wrote:
Doug White
news:UbYXm.425994$Jp1.4...@en-nntp-02.dc1.easynews.com:
> The large open end ones with ribbon wire - are called 'corn cob' power
> resistors.
>
> I have two smooth sided resistors - each 8 ohm (nice speaker loads)
> but must be 1000 watt. I'd have to look. I also have a 1/2 ohm IIRC
> corn cob. Nice to measure current flow in a circuit - voltage drop.
>
> $33 isn't bad for that - I'm surprised myself.
>
> If you get one, look for mounting hardware. It helps. Or you make
> some.
I like the ones in aluminum housings, like these:
http://www.token.com.tw/resistor-pd/power-resistor-ah.htm
They are less fragile than the ceramic ones, and tend to be a bit smaller
for a given rating. Several vendors make them, and they are available
surplus from time to time. Be careful with the power ratings, however.
They assume a certain level of air flow & heat sinking for continuous
duty. For the 200W braking resistor, you could probably get away with a
200 W rating without heroics because the load is transient.
Doug White
Bill McKee
"Doug White" <gwh...@alum.mit.edu> wrote in message
news:Xns9CE9577D14305...@69.16.186.50...
Give a call to http://www.halted.com/ large surplus dealer in Sunnyvale.
Gunner Asch
wrote:
Some other styles....
http://omniturn.com/bin/RepairParts/rp_additional_components.htm
A bit pricey however.....<G>
Joseph Gwinn
Gunner Asch <gun...@lightspeed.net> wrote:
> On Tue, 22 Dec 2009 13:36:02 GMT, Doug White <gwh...@alum.mit.edu>
> wrote:
>
> >"Martin H. Eastburn" <lion...@consolidated.net> wrote in
> >news:UbYXm.425994$Jp1.4...@en-nntp-02.dc1.easynews.com:
> >
> >> The large open end ones with ribbon wire - are called 'corn cob' power
> >> resistors.
> >>
> >> I have two smooth sided resistors - each 8 ohm (nice speaker loads)
> >> but must be 1000 watt. I'd have to look. I also have a 1/2 ohm IIRC
> >> corn cob. Nice to measure current flow in a circuit - voltage drop.
> >>
> >> $33 isn't bad for that - I'm surprised myself.
> >>
> >> If you get one, look for mounting hardware. It helps. Or you make
> >> some.
> >
> >I like the ones in aluminum housings, like these:
> >
> >http://www.token.com.tw/resistor-pd/power-resistor-ah.htm
> >
> >They are less fragile than the ceramic ones, and tend to be a bit smaller
> >for a given rating. Several vendors make them, and they are available
> >surplus from time to time. Be careful with the power ratings, however.
> >They assume a certain level of air flow & heat sinking for continuous
> >duty. For the 200W braking resistor, you could probably get away with a
> >200 W rating without heroics because the load is transient.
> >
> >Doug White
>
>
> Some other styles....
>
> http://omniturn.com/bin/RepairParts/rp_additional_components.htm
Do you know what these braking resistor units weigh? (Not shipping
weight, actual weight.)
The reason to ask is to estimate the amount of heat they can absorb
without allowing smoke to escape.
> A bit pricey however.....<G>
But pretty.
Joe Gwinn
Gunner Asch
wrote:
>In article <sqf2j59bm2o0qfc6s...@4ax.com>,
Ayup..they are about 1-1.5 lbs. They can absorb a SHITLOAD of heat,
and transfer it to whatever they are bolted to. I think the big units
rated for Short Cycle are about 5lbs or a bit more.
4000 rpm to zero in less than a second, loading, then back to 4000 rpm,
then back to zero..often times every 3-5 seconds all day long.
>
>The reason to ask is to estimate the amount of heat they can absorb
>without allowing smoke to escape.
>
>
>> A bit pricey however.....<G>
>
>But pretty.
>
>
>Joe Gwinn
Gunner, OmniTurn Service tech
Bill Noble
a reasonable selection of large surplus resistors
"Bill McKee" <bmckee...@ix.netcom.com> wrote in message
news:ENSdnbOBs9L0vKzW...@earthlink.com...
Gunner Asch
<nob...@nowhere.invalid> wrote:
>another good source is Ford Electronics in Fullerton CA - they used to have
>a reasonable selection of large surplus resistors
They are about 5 minutes from my shop in Fullerton. Ive driven by there
a number of times in the past month. Ill have to stop in and see what
they have.
Gunner
Joseph Gwinn
Gunner Asch <gun...@lightspeed.net> wrote:
Thanks, that gives us the scale.
For the record, the Hitachi braking resistors JRB 120-series (120 watts)
weigh 0.27 Kg (0.59 lbs), SRB-200-series weigh 0.97 Kg (2.13 lbs),
SRB-300 weigh 1.68 Kg (3.70 lbs), and SRB-400 weighs 2.85 Kg (6.27 lbs),
according to the datasheet.
I have a JRB-120-3 (50 ohms) on the Clausing 5914 lathe's SJ100 VFD, and
I can trip the VFD if I stop too quickly with a big chuck installed.
Don't recall if I can use a lower resistance or not. But I can stop in
2 or 3 seconds, which is good enough for a manual lathe.
Joe
Bill McKee
"Gunner Asch" <gun...@lightspeed.net> wrote in message
news:uqr2j55kmic55gkbi...@4ax.com...
Big light bulbs. Resistance may be wrong, but they absorb a lot of energy.
We used a bank of light bulbs as a dummy load on a TACAN unit. Absorbing
3000 watts.
Carla Fong
Bill McKee wrote:
> Big light bulbs. Resistance may be wrong, but they absorb a lot of energy.
> We used a bank of light bulbs as a dummy load on a TACAN unit. Absorbing
> 3000 watts.
We've had good luck using ordinary hardware store kitchen range heater
elements (tradename Calrod). Cheap, low resistance, high power dissipation.
Carla
Next time you're stopped, just jump out and DEMAND proof of probable
cause. Don't forget to call him PIG! and JACKBOOTED THUG! Ask for his
badge number. Tell him you pay his salary. They like that.
David Lesher
>They are less fragile than the ceramic ones, and tend to be a bit smaller
>for a given rating. Several vendors make them, and they are available
>surplus from time to time. Be careful with the power ratings, however.
>They assume a certain level of air flow & heat sinking for continuous
>duty. For the 200W braking resistor, you could probably get away with a
>200 W rating without heroics because the load is transient.
Put them in a can full of transformer oil of some type.
David Lesher
>another good source is Ford Electronics in Fullerton CA - they used to have
>a reasonable selection of large surplus resistors
Echo re: Halted. Also try a query to Mendelson's -- meci.com &
electronicsurplus.com in Mentor OH. They will have items not in their
catalogs. There are other places too; maybe Skyline in Orlando.
Figure on some choices you can use series/parallel. IOW, if you need 10
Ohms, you can buy not just two 5 ohm resistors, but three 30 Ohms, etc.
RoyJ
get them for $1 each at the appliance recycling place. 2 in series would
be perfect, would max out at 3000 watts dissipation.
GeoLane at PTD dot NET wrote:
Gunner Asch
Indeed. Should work quite well as long as the ohms range is within what
the VFD is expecting.
I did some mods to the VFD running my Gorton MasterMill..and the Yaskawa
MP3 Vfd really diddnt like resistors below or above the range specified
in the manuals.
Gunner
>
>Carla
>
>Next time you're stopped, just jump out and DEMAND proof of probable
>cause. Don't forget to call him PIG! and JACKBOOTED THUG! Ask for his
>badge number. Tell him you pay his salary. They like that.
Gunner Asch
Excellent!! Thanks!!!
Gunner
Martin H. Eastburn
Calrod heater elements can be bought at Lowe's and sockets
for them as well. Mounting is a little tricky - but they
don't get very hot so almost anything goes. Since the rod is
ceramic you can't short it out except at the connection end.
Martin
Gunner Asch wrote:
> On Tue, 22 Dec 2009 20:48:55 -0800, Carla Fong
> <carla.xs...@verizon.net> wrote:
>
<snip>
Martin H. Eastburn
to smoke - smells of peanuts.
Caution - old - read that old transformer oil can give you cancer.
Power line transformers are time-bombs and most have over the last 50
years been replaced.
Just know what you use.
Oil can be a good heat sink assistant. e.g. put the resistor in a 5 gallon
can or 25 - what ever it takes - and add oil. the whole can absorbs.
It might be a tank attached to the legs of a machine that has oil -
something like the coolant oil. A sheet metal box.
Martin
Bill McKee
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:tyAYm.196620$Td3....@en-nntp-01.dc1.easynews.com...
The old transformers had PCB oil. When one blows up, makes a hazardous
waste site for awhile.
Bill Noble
possibly be nearby or passing by is allergic to peanuts - it is a common
allergy now, and those who have it can go into shock from the vapor from
peanut oil -
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:tyAYm.196620$Td3....@en-nntp-01.dc1.easynews.com...
David Lesher
I do like the idea of Calrod or similar stove elements. If you can
find the correct resistance, great. They are sturdy and high wattage.
Immersing them in oil is better.
>> Caution - old - read that old transformer oil can give you cancer.
>> Power line transformers are time-bombs and most have over the last 50
>> years been replaced.
No one will give/sell you PCB oil, unless they want to die filling out
EPA reports. Any transformer oil you can buy today won't be that. I
believe mineral oil will work but not as well.
"Bill Noble" <nob...@nowhere.invalid> writes:
>beware of peanut oil if anyone nearby, or who might be nearby, or who might
>possibly be nearby or passing by is allergic to peanuts - it is a common
>allergy now, and those who have it can go into shock from the vapor from
>peanut oil -
I have a peanut allergy, and was told by an allegist that when they make
the oil, they remove the part that causes the reactions. I know various
fastfood places use it for chicken, and I've never had a reaction.
Michael A. Terrell
Gunner Asch wrote:
>
> On Sun, 20 Dec 2009 23:53:58 -0500, GeoLane at PTD dot NET <GeoLane at
> PTD dot NET> wrote:
>
> >
> >My Teco VFD specifies a 70 Ohm, 200 Watt braking resistor. I did
> >some quick looking on eBay and Mouser. It looks like the least
> >expensive ones are the open tube ones - BUT at around $33 and up. Is
> >there a less expensive place to buy these or a different way to search
> >either site that would bring up the less expensive alternatives?
> >
> >
> >RWL
>
> simply operating it HSM and not doing rapid starts and stops ie CNC.
>
> Surplus houses often have similar resistors btw....google is your
> friend.
>
> Such as this page....time to find it less than 1 minute...
>
> http://www.surplussales.com/resistors/WireWound/WW70-110.html
https://www.fairradio.com/catalog.php?mode=view&categoryid=4230
RS-200 - 200 ohm, 100 watt Resistor, $2.00 each
RS-113 - 200 ohm, 113 watt Resistor, $2.25 each
Use three in parallel for 66.6 ohms at 300 or 339 watts. If one ever
fails, you still have a 100 ohm 200 or 226 watt load.
--
Offworld checks no longer accepted!
Michael A. Terrell
Light bulbs aren't reliable.
Gunner Asch
For those using lower value VFD braking resistors...
RS-35 - 35 ohm 200 watt Resistor,
$4.00 each
Fascinating! Bookmarked!!!
Michael A. Terrell
You're welcome. Fair Radio was always one of my favorite surplus
stores. It was easy to spend the entire day digging through the stuff
they don't catalog. :)
GeoLane at PTD dot NET
<mike.t...@earthlink.net> wrote:
>
>
>https://www.fairradio.com/catalog.php?mode=view&categoryid=4230
>
>RS-200 - 200 ohm, 100 watt Resistor, $2.00 each
>
>RS-113 - 200 ohm, 113 watt Resistor, $2.25 each
>
>
> Use three in parallel for 66.6 ohms at 300 or 339 watts. If one ever
>fails, you still have a 100 ohm 200 or 226 watt load.
Now those are good prices.
I spotted another one that would work well also - 35 Ohms / 200W.
String two of them in series to get the 70 Ohms.
After posting my query to the group, I emailed Factorymation the day
before Christmas asking what the Teco would tolerate without any
braking resistor. I'm awaiting a reply at this point.
As cheap as those ones from Fair Radio though, it might be worth
adding them as an inexpensive insurance policy.
RWL
Michael A. Terrell
GeoLane at PTD dot NET wrote:
>
Definately. Better to have them and not need them, than have the tool
die becasue you didn't. :)
--
Greed is the root of all eBay.
Paul Hovnanian P.E.
>
> "Ignoramus15449" <ignoram...@NOSPAM.15449.invalid> wrote in message
> news:W6KdnaXPytjgD7jW...@giganews.com...
> > On 2009-12-14, Greg O <goo...@hotmail.com> wrote:
> >> Pics with the VFD mounted, and all up and running. I actually produced
> >> some
> >> chips with it today.
> >>
> >> http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFDmounted.jpg
> >>
> >> http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFD.jpg
> >>
> >
> > Looks way cool. Where is the switch, though?
> >
> > i
>
> Switch? Switch for what?
> I got it set up to run it all through the VFD, and axed the factory on-off
> switch. I have forward/reverse, jog, start, and stop. I have the braking set
> to one second, which is the lowest setting, so at any speed it will come to
> a complete stop in one second, or less. When running the VFD at 30 hertz,
> and the variable speed cranked all the way down, about 60 RPM, the spindle
> will stop in 1/2 a revolution.
> What more do you need?
> Greg
A big, red e-stop button hat you can slap when one hand gets wrapped
around the chuck.
--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
You're only supposed to blow the bloody doors off!
Paul Hovnanian P.E.
>
> "Steve W." <csr...@NOTyahoo.com> wrote in message
> news:hg6e13$g0k$1...@aioe.org...
> > Greg O wrote:
> >> Pics with the VFD mounted, and all up and running. I actually produced
> >> some chips with it today.
> >>
> >> http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFDmounted.jpg
> >>
> >>
> >> http://i734.photobucket.com/albums/ww343/PoorUB/Powermatic%201200/VFD.jpg
> >>
> >
> > you can mash when things go wrong and stop it NOW.
> >
> > --
> > Steve W.
>
> The stop button stops the spindle in one second. Fastest braking this VFD
> will do.
> Good enough "oh shit" button for me.
> Greg O
The membrane switch on the VFD panel? Try whacking that in a panic?
Get a real 'big red button'.
--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
Yeah, but you're taking the universe out of context.
Greg O
"Paul Hovnanian P.E." <pa...@hovnanian.com> wrote in message
news:4B36C93C...@hovnanian.com...
No clue why my hand would be anywhere near the chuck with the drill running.
I figure the one hand will be on the feed handle, and the other hovering
over the stop button, or the reverse. I have run drill presses in the past
that make this tning look like a baby. Never needed a e-stop button, and my
hands were never near the working end of the drill press. Running a 5 HP
gear head drill press you clamp the work down good, and stay out of the way.
Same practice I will use with this one.
Greg O
Ignoramus9012
nicely for me.
i
Bruce L. Bergman
That drum switch is NOT a proper "Big Red Panic Button" that you can
mash if things go very wrong, and we both know it. Install one, NOW.
Better yet install two, one high and one low. It doesn't have to be
beautiful, it just has to work.
Do you really want 100 of your best buds all yelling "I Told You
So!!" as you learn to type while short a digit or two for the rest of
your life? Or worse, the whole arm?
Oh, and that drum switch better be connected as a signal-level input
to the VFD, and not be line voltage between the VFD and the motor.
Most VFD's do NOT like it when you open the motor leads under load,
the Magic Smoke tends to escape from the transistors.
--<< Bruce >>--
Ignoramus27446
> On Sun, 27 Dec 2009 00:39:14 -0600, Ignoramus9012
><ignora...@NOSPAM.9012.invalid> wrote:
>
>>My Powermatic 1200 has a reversing switch. It seems to work very
>>nicely for me.
>>
>>http://igor.chudov.com/projects/Powermatic-1200-Drill-Press/02-VFD-Installation/02-VFD-Installation-5845.jpg.html
>>
>>i
>
>
> That drum switch is NOT a proper "Big Red Panic Button" that you can
> mash if things go very wrong, and we both know it. Install one, NOW.
> Better yet install two, one high and one low. It doesn't have to be
> beautiful, it just has to work.
>
> Do you really want 100 of your best buds all yelling "I Told You
> So!!" as you learn to type while short a digit or two for the rest of
> your life? Or worse, the whole arm?
I definitely do not. OTOH, I have never seen a drill press with such a
button, either.
> Oh, and that drum switch better be connected as a signal-level input
> to the VFD, and not be line voltage between the VFD and the motor.
> Most VFD's do NOT like it when you open the motor leads under load,
> the Magic Smoke tends to escape from the transistors.
Yes, 10v signal level input.
Gunner Asch
Damned straight. And not!!! switching the motor leads under VFD is
something Ive mentioned time and again here.
Gunner
"I am for doing good to the poor, but I differ in opinion of the
means. I think the best way of doing good to the poor, is not
making them easy in poverty, but leading or driving them out of
it. In my youth I travelled much, and I observed in different
countries, that the more public provisions were made for the
poor the less they provided for themselves, and of course became
poorer. And, on the contrary, the less was done for them, the
more they did for themselves, and became richer." -- Benjamin
Franklin, /The Encouragement of Idleness/, 1766
Bruce L. Bergman
>On 2009-12-28, Bruce L Bergman wrote:
>> On Sun, 27 Dec 2009 00:39:14 -0600, Ignoramus9012 wrote:
>>>My Powermatic 1200 has a reversing switch. It seems to work very
>>>nicely for me.
>>>
>>>http://igor.chudov.com/projects/Powermatic-1200-Drill-Press/02-VFD-Installation/02-VFD-Installation-5845.jpg.html
>>
>> That drum switch is NOT a proper "Big Red Panic Button" that you can
>> mash if things go very wrong, and we both know it. Install one, NOW.
>> Better yet install two, one high and one low. It doesn't have to be
>> beautiful, it just has to work.
>>
>> Do you really want 100 of your best buds all yelling "I Told You
>> So!!" as you learn to type while short a digit or two for the rest of
>> your life? Or worse, the whole arm?
>
>I definitely do not. OTOH, I have never seen a drill press with such a
>button, either.
Then you haven't been looking very hard, Iggy. Or you simply choose
not to see...
The vast majority of the power switches on newer drill presses and
saws and such (unless they are imported from Elbonia) are right out in
front, and are a hybrid Push-Pull Toggle hinged at the top. Pull out
from the bottom to turn on, mash in to turn off.
The fancy ones on stationary tools have a Key Pin you have to insert
to turn it on, and if there are kids in the house you can take the
plastic key out and hide it. Keeps the under six set from losing an
arm.
The "keys" I've seen are easy to defeat with a sliver of wood and a
little whittling, but if the kid is old enough to defeat the lock he
should also be old enough to realize the tool can be dangerous.
>> Oh, and that drum switch better be connected as a signal-level input
>> to the VFD, and not be line voltage between the VFD and the motor.
>> Most VFD's do NOT like it when you open the motor leads under load,
>> the Magic Smoke tends to escape from the transistors.
>
>Yes, 10v signal level input.
Good. And you used a hunk of CAT-5 cable (4-pair) between the VFD
and the switch, right? Should have taken two pair tops. So take a
spare pair and hook the NC contacts on a mushroom head Panic Button to
the E-Stop contacts on the VFD.
And the second remote switch down low or a few feet away can't hurt
- if there's a large piece of work spinning around on the chuck, you
might not get close enough to hit the button on the machine...
If I was running a CNC Shop where I wanted to start the machine and
let it do it's thing as I wander away to do something else, like
paperwork...
I'd have a video camera on each machine and a monitor on my desk -
with a remoted Little Yellow button for a regular machine stop (to go
out and replace a broken tool without losing the zero and the program)
and a Big Red Button for E-stop if you see (and/or hear) a full-on
crash happening.
Remember our r.c.m motto: Safety Third.
--<< Bruce >>--