Testing Regan resistor

[UBRacing]

I' have tried to get hold of the local service center but they never did ever call me back.

I'm been fighting with this 95 haas VMC

I been getting over voltage alarms. Its fine if I run it at 50 % rapid or less but its to slow :-)

Does any one know the procedure to test the regan resistor ( sp?)

From the research I been doing on the forums it looks like it could be the problem.

Thanks

For any help!

[PBMW]

Wow...
Local service center never called back.
I'm shocked

I've had the same thing happen to me.

As a matter of curiosity, Is this machine on real three phase or are you using a converter? Does it have a Delta wye transformer?
The reason I ask is that I have an SL10 that will low voltage alarm on hot days and with many spindle accells and decells...
I am on a Phase Perfect with no transformer. So am curious if that may have anything to do with it.

[serviceman]

the first thing you need to do is check the incoming voltage on the machine and make sure the taps on the transformer on the bottom right of the cabinet are set properly. the only way to test the regens is to ohm them out but haas had a lot of different regen styles and can have many ohm reading anywhere from 8 ohms to 12 ohms for 20 hp drives if they are not smoking and getting real hot theres probably nothing wrong with them. you can check them for shorts to ground also. if your machine is a vector drive you need to make sure the dc buss voltage is around 325 vdc this will go up and down with the taps. you can also have a bad motor if it is a dc machine.

[UBRacing]

HI, I'm on a phase convertor. I have this in my home shop so I needed a convertor to get three phase.

I'm pretty new to this so don't LOL if you confuse me bit :-)

We checked the taps coming in and the voltage stays constant even when I get the overvoltage alarm. And they are set in the correct voltage location.

I had also been getting a phase loss 1-2 alarm before but I managed to turn that off in the parameters. Not sure if thats related to the same deal.

The regen is not hot I have checked it.

The problem always seems to be when the spindle starts up and goes to make a rapid move after a tool change most of the time. Soem times it will do it with out a tool change.

Is there a parameter to change so the spindle is up to full speed before it makes a rapid move? Thought I seen that some were on the forums.

Might be enough to patch it till I can get a tech to look at.

Worst part is i'm about 8 hours form the service place :-(

[UBRacing]

One other thing is when I watch the DC Buss it normally runs 157-160V.

When I get the overvoltage alarm it climbs up to 183v then slowly goes back down to 157v.

If that helps.

[RDesign]

When I first bought my TM1 I would get an overvoltage alarm when the spindle stopped from higher RPM's. - maybe that is the opposite problem you have maybe but I hope this helps...

A TM1 is a little different power supply that you have but this is what I did...
I have two wires going up to a pair of stove-top looking resisters. After the power was disconnected long enough the 320VDC supply had discharged I disconnected those two wires. I measured 8 Ohms across them which was in the range of other posts I had found on this site.

I reconnected the wires, hooked up my mulitmeter set it to record min/max powered up the machine and stopped the spindle from 2000rpm. Looking at the meter the voltage never peaked at all - the power supply never dumped load to the resistors.

I ran a similar test this time checking the dc voltage level, it peaked at almost 400VDC before the power supply shut itself down. Normal for me is 324-325VDC.

For me it took a $2700 power supply to fix. Your problem sounds different but I would still check the regen circuit resistance and operation.

Good luck

[serviceman]

have you tried running at 50% or 25 % rapid? you can also slow the accell down on the spindle.

[UBRacing]

Hi. I been running it at 50% rapids then I don't get any overvoltage.

How do I slow the accell on the spindle?


Thanks

[gar]

071119-2102 EST USA

UBRacing:

Does your machine have brushless motors? If not I believe you have two different DC buses.

If the spindle is an induction motor, then you will have a variable frequency drive for that motor, and I believe it has its own DC supply.

I believe the DC bus voltage you have mentioned is for the servos.

On acceleration there is never a need for a regen resistor load. This is only necessary on deceleration to absorb excess energy that would force the DC power supply capacitors to too high a voltage.

.

[Geof]

Originally Posted by UBRacing Hi. I been running it at 50% rapids then I don't get any overvoltage. How do I slow the accell on the spindle? Thanks

Parameter 196 ACCEL LIMIT LOAD; factory set at 195 and you can reduce it to whatever you want.

There is also another Parameter that you can look at. Parameter 209 COMMON SITCH 2. This has two columns of entries and near the bottom of the right column is one called SPNDL NOWAIT. When this is 1 if the command line following an M03 is a rapid move the machine will rapid while the spindle is accelerating, when it is 0 the machine waits until the spindle comes up to speed before doing the rapid.

Normally you do not get an overvoltage alarm during acceleration but because you are running on a phase convertor I wonder if the way the phase convertor responds to a sudden load has anything to do with it. I have a diesel generator running a Super MiniMill. When the machine starts up the spindle and does a rapid at the same time the diesel fires up to full throttle to handle the load and the three phase supply voltage droops a little, then when the spindle is at speed and the rapid move stops the power draw from the machine drops very quickly and the diesel overruns briefly spiking the three phase voltage up. Perhaps a rotary phase convertor responds in a similar manner to a sudden short load, drooping first then peaking for a very short time immediately after the load is removed. You could try putting an analog voltmeter on your incoming lines to see what the voltage does during the machine start up.

[UBRacing]

Thanks Geof I will give that a try.

[gar]

071124-1030 EST USA

Our 1993 HAAS uses a Magnetek GPD 503 spindle drive. This has its own DC bus and a pair of large regen resistors in series inside the rear enclosure. These have a total series resistance of 19.4 ohms. Each are a nominal 10 ohms and probably rated 200 W each.

The DC bus for the servos is labeled as 160 in the HAAS manual. This is for the DC brush type servos. The regen resistor is a single resistor about 1/2 the size of one of the others and has a resistance of 51 ohms.

I only see one over temperature sensor and that is close to the 51 ohm resistor. The HAAS manual might imply two different over temperature sensors.

HAAS machines with brushless DC servos (actually AC synchronous motor with commutation sensors) use one DC bus for both the spindle and servos and this is 325 V. Thus only one regen resistor and this is more logically located outside of the enclosure.

.