Need help with 3-Phase Lathe motor VFD error please

I'd guess the VFD- it's presumably ~10 years old, about time for the caps to be dying.

(spec%20A%20_%20E).pdf&FileType=Manual

A couple of thoughts. I have a vfd on my lathe. When I disconnect the pow er the fan on the VFD continues to run until the caps are discharged. Have you noticed this? And if you have is the time before the fan stops short er than it was.

I would check the DC voltage on the caps. Be very careful in doing this. Make sure the power is completely disconnected for say five minutes before opening the case. Then take a insulated wire with bare ends and put the e nds across the big capacitors. Fasten the wire to some wood dowel or equiv alent with electrical tape so you do not have to have you hands close to th e capacitor terminals. Now connect your multimeter across the caps and s et to high DC volts before applying power. Is the voltage about what you w ould expect? About 1.4 times the input voltage to the VFD.

Shut the power off and discharge the caps as above before disconnecting the multimeter.

Better yet is to get a friend who knows electronics and have him show you how to check the voltage on the caps.

Dan

kawa (EMS) 606 PC3 VFD.

ramming panel.

ess, and then the Control & VFD alarm out with a spindle fault. On the VFD it shows a Over/Under Voltage fault light, stopping the motor.

alarm briefly flashes red, then status goes back to normal (flashing green ).

seconds rate.

into and out of machine's main power switch.

l 3-Phase power, not running an RPC.

e EM contactor's voltage checked OK in/out, as far as i can tell, but that could certainly still be at fault intermittently. Need a way to monitor Vo ltage changes as the fault occurs I guess.

r on all 3 legs.

else in the power system's input to the VFD?

nual

Hi,

Yes it is over 10 years in fact. So I suppose i should not complain too mu ch ;-(

So that is a common failure mode for a VFD then? When the Caps go they voltage alarm?

Thanks for the link, BTW i had already found and read that. RTFM I can do!

That manual says a bad EM contactor might cause UV/OV alarms, which is why I was thinking that might be the reason. Oh well.

Now how about a source for a new VFD to fit my spec?

Thanks.

ower the fan on the VFD continues to run until the caps are discharged. Ha ve you noticed this? And if you have is the time before the fan stops sho rter than it was.

Make sure the power is completely disconnected for say five minutes befo re opening the case. Then take a insulated wire with bare ends and put the ends across the big capacitors. Fasten the wire to some wood dowel or equ ivalent with electrical tape so you do not have to have you hands close to the capacitor terminals. Now connect your multimeter across the caps and set to high DC volts before applying power. Is the voltage about what you would expect? About 1.4 times the input voltage to the VFD.

he multimeter.

u how to check the voltage on the caps.

Thanks.

Drives Warehouse.

awa (EMS) 606 PC3 VFD.

amming panel.

ss, and then the Control & VFD alarm out with a spindle fault. On the VFD i t shows a Over/Under Voltage fault light, stopping the motor.

alarm briefly flashes red, then status goes back to normal (flashing green) .

into and out of machine's main power switch.

3-Phase power, not running an RPC.

EM contactor's voltage checked OK in/out, as far as i can tell, but that c ould certainly still be at fault intermittently. Need a way to monitor Vol tage changes as the fault occurs I guess.

on all 3 legs.

else in the power system's input to the VFD?

Thanks for all the help.

To follow up, I'm going to try the "repair the one I've got" route. Two quotes so far, one for $450, other is $660. 1-yr warranty, week or so turnaround.

This drive is too old to find a direct replacement, at least I've not been able to, and the new V1000 series from Yaskawa is what the upgrade path wou ld be for my old model 606 PC3 (CIMR-PCU23P7).

Looks to me like upgrading to the V1000 would require some added work in th e mounting, wiring, and programming for my application. Cost also looks to be higher, as far as I've been able to get any prices. An Ebay V1000 is g oing for about $750. Might be better prices out there, but I'd like to avo id a major "science project" in figuring out/putting this back together.

If anyone has a favorite AC drive repair house, I'm getting quotes now, and would welcome contact info for any good places you might have experience w ith.

T'care,

On 2013-08-22, snipped-for-privacy@krl.org wrote:

Better to use a moderate value resistor (maybe about 100 ohms) capable of handling 50 Watts or more ( it would take closer to 1200 Watts if you were leaving it connected while power was applied, but for the time needed to discharge the capacitors, 100 Watts shodlu suffice. The really high surge from shorting the terminals can shorten the life of the caps if they are still fully functional.

I would actually expect the same DC voltage even on quite old caps, as long as they have *some* capacitance and the VFD is not driving a load. Better to have it driving a load, and to measure the AC across the caps, (which will show how well the capacitor is holding the voltage up between charging cycles from the power line.) If both measure the same, then both are probably good. Expect perhaps as much as 50 VAC on one powered from 240 VAC if the load is close to a full load. If it is less near a full load, they are in pretty good condition. If it is significantly greater, the caps are letting the voltage get too low, and that is triggering the voltage limit alarms. (Hmm ... that 50 VAC was assuming a single phase power to the VFD -- with your full three phase, if it gets much below 25 VAC consider replacing the caps. They ware easy to spot -- bit fat long cylinders with two screws on one end. (When replacing them, beware that each terminal is either positive or negative -- the positive will have either a red dot near it, or a '+' molded in the top. These must go exactly as the old ones were oriented, and likely they will be arrange so the positive side of one will be near the negative side of the other, so check both cap's orientation when you take the board connecting them off. (And be sure to discharge them as above just before touching the screws.) With my test equipment, and my knowledge, I would perform the tests live, but if you are not experienced, the above path with discharging is much safer. A simple slip could result in a fat arc and blobs of molten metal spraying around.

Good Luck, DoN.

Its the VFD. You have lost either a can (capacitor) or there are chips on the traces (blow it out with high pressure air...with the power OFF)

Hows that AW=100 been working out for you? Was it one of those with the Omniturn control and slide or one of the later versions?

Ive serviced several of the Omniturn cored ones..the later ones were trash and there is NO data around for them.

Gunner

"There are no leftists in mainstream American politics.

Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013

They are easily replaced btw.

Very common

And its nearly identical to my slightly later model PC3 that ate shit. It was running my Gorton Mastermill and finally died. One of these days Ill replace it.

It was such a reliable drive that everybody put their label on it

Hell..you can even stick in a GS2 drive...but you will probably need to change the breaking resistor to a different value (and will need to be 200 watts)

"There are no leftists in mainstream American politics.

Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013

$410 for a 5hp

Decent drives..but check ebay

Gunner

"There are no leftists in mainstream American politics.

Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013

Thank you for this vivid warning Don.

I will endeavor to avoid any flying blobs of molten metal as I work this through. I know when I'm in over my head, being somewhat more comfortable with SW than HW.

Drive is now securely packed up for a trip to Precision in VA for a full overhaul.

Thanks Gunner,

Yes, my VFD is now on the way to be rebuilt by an outfit in VA. I'll let you know how that works out.

GS2 looks like a nice drive at a fair price.

The AW100s (two of them) have run 8-hrs every work day for the past 13 or 14 years. They were both the last and latest of the versions with all AW controls.

One made in 1998, other a 1999 model year.

I've heard your opinion of them before, I respect your experience, but for me they have been excellent lathes.

I've maintained them myself, and have upgraded things like switching to an LCD monitor, and a CF card hard drive. Course good Sony floppy drives are getting scarce ;-)

For what it's worth, I NEVER power them down. I think that has been one of the reasons they still work as well as they do.

I've collected enough spare parts and sources over the years to keep them running a bit longer I hope. Most of the parts AW used were off-the-shelf stuff and is still available.

5C spindle still runs tight and true, and the ball-screws & ways get greased twice a year. Found a good company to rebuild the way-covers to better than original condition. The Baldor DC-brushed axis servos are still rebuildable, and I keep a couple of spares to swap in when needed.

The only thing that can't be sourced now is the AW control board itself.

If I can get 3 or 4 more years from these lathes it won't matter anymore as I'll be retired. Heck I'm semi-retired already. Really only keep doing what I do because it's still fun.

When I bought these machines there was quite a controversy about a DOS based control. Everyone on AMC and RCM said it would never work. However, time has proven it to be a viable approach. The DOS-based control has been rock solid for me.

Thanks again for your help. T'care

So where they the non OmniTurn versions? If you copy your paperwork..you could probably sell a number of them on Ebay. Speaking of which..there is or was another one on Ebay a week or so ago. I dropped em a message asking if it were Omniturn guts..but never did hear back from them.

A very good decision.

Same way with the OmniTurns themselves. I seldom buy parts from the factory.

Got a link?

Cool!

DONT TALK ABOUT THAT BOARD!! Bad luck to speak of something made of unobtainium.

Fair enough! I only work because Ive become accustomed to food. Shrug.

You to!

Gunner

"There are no leftists in mainstream American politics.

Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013