[Trebol]

Hi all.
Without my A axis connected the Fadal starts and CS's fine in XYZ.
With the A axis connected (VH65) I get the following two error messages:

A Axis:
Error 1
Motor Overload

And it will not allow a CS (after pushing Jog to reset, the axis controllers are reset, but the issue continues and will not allow the machine to start).

From the manual, Error 1 is a faulty resolver. Is it possible that the issue is simply a faulty resolver and the motor message is just in sympathy with this (ie. no movement from the motor because the resolver is faulty, so the system thinks the motor is jammed as well, when it is really just a basic relover problem?) or is there something deeper here??

Would like to test the resolver (J1 and J2 1.6-1.7 Vdc) but for whatever reason I don't see a voltage on any axis when I do this (even when just running OK in XYZ only...) and sometimes the axis' will jump when I put the voltmeter across J1 and J2, so I thought I would wait for replies..

Thanks for your thoughts,

Cheers,
Marty.

[alex gitzel]

you need to put the dummy plug in,when you take off the a-axis wire.check in the rear cabinets for it.

[Trebol]

Hi.
Just to be clear:
"Without my A axis connected the Fadal starts and CS's fine in XYZ."
That is with the dummy plug in as per normal XYZ operation.

"With the A axis connected (VH65) I get the following two error messages:"
This is with the dummy plug out and the A axis connected as mentioned.

Thanks, any advice on this combination of faults and whether this could simply be a basic resolver issue (DC machine) would be appreciated.

Kind regards,
Marty.

[Trebol]

Hi Neal.
Just saw your PM. Thanks for getting back to me. Wondering with this combination of messages (and I know this will be hard to estimate) but at a guess what likelyhood is it of being a pure resolver issue?
Thanks again,
Marty.

[iess525]

Hi Marty,

Give me a call at the office and we'll help you out.

-Shelvin
TheFadalParts.com
(818) 678-9456

[Neal]

Marty--
Both of those error messages will come up with a resolver fault. If this is a DC motor take the lowest cable that plugs into the 1010 controller card and measure the voltage on the coaxial connector. It sould read approx 1.8 volts DC. if has no voltage the either the cable is bad, the resolver is bad or no voltage is getting to the resolver.

Neal

[Trebol]

Thanks for the reply Neal.
With regards to voltage testing of the coax (1.8V) into the 1010 board, against what am I measuring the voltage eg. is J1 to J2 or the voltage across the coax to the machine chassis (earth) or something else??
Thanks again.

[Neal]

Measure the bottom coax from outside the plug shell to the center core of the wire.
Neal

[Trebol]

Hi Neal.
Sorry about the delay, I've been away for a few days.
Hoping to ask you what I'm sure will be a silly question...
Attached is a picture of the lower portion of the 1010 cards. To the left the XYZ and to the right the A.
To get a baseline and to make sure I'm doing this right I have been trying to measure the voltage at the lower coax plug on the 1010 card (to check resolver voltage) at either XYZ (which I know are working) before moving to A (whose resolver is in doubt).
I have tested as you suggested, from the core of the lower coax to its jacket, with the cable plugged in, disconnected and testing at the plug, disconnected and testing at the socket (card) end etc...
Seemingly no matter what I do I can't get a reading across an axis that I know is working. Obviously I'm hoping to get this squared away so that I can get a meaningful test done on the A axis to determine whether the A issue is in fact the resolver. The only other thing I can think of is maybe there needs to be a test program running and the axis moving to see a following voltage there whilst measuring??
Could you give me the step by step rundown on this test that you might otherwise save up for dummies because I sure feel like one...
Either that, or my axis' are running fine on zero voltage
Thanks for your help.
Kind regards,
Marty.

[denmar]

..

[Trebol]

Hi.
Just ran the resolver test on the X axis (end of the J1 plug to the end of the J2 plug on the 1010 board while the X axis resolver program is running) and got the voltage at 1.8V. Just as expected for a working resolver and to set the baseline for the test.
Problem is that when I take the dummy plug out and connect the A axis the machine will not start up as it has the constant error on the A axis, therefore I cannot run a resolver program to test the voltage on the A axis.
I did however test the resisitance of the resolver with the A axis disconnected. (All units in ohms)...

_________Manual________Mine
Pair A____70 to 80_______50
Pair B____190 to 220_____136
Pair C____190 to 220_____136

So all I can do is suspect a resolver pending any other thoughts??
Thanks,
Cheers,
Marty.

[Neal]

Siknce the 1.8v is at the bottom connetor at the 1010 controller card indicates that the resolver is ok. Look for motor, controller card or amp issue.

Neal

[Trebol]

Sorry Neal maybe I wasn't clear, I got the 1.8V testing an axis I know is working (the Z axis) to make sure I was doing the test right. Unfortunately I now can't do this test on the faulty axis (the A axis) because the machine errors out every time it is connected. Therefore all I can do is test the resistance of the resolver while it is disconnected and these seem to be off... (See figures above).
Thinking I'm going to have to get a resolver and just assume that is the issue. Just wondering if there were any final thoughts.
Thanks,
Marty.

[denmar]

The A axis was working before? and suddenly you got all this problems?

[Trebol]

Yes.

Was able to test the resolver just now, 1.7V so OK. From a FADAL tech, suspected motor burned out, same amp card as the XYZ axis which is apparently too much for the smaller motor in the VH65. Was advised that XYZ motors are around 15-20 amps whereas the rotary motor is more like 7.5 amps and hence needs a lower output Amp card...
Will take the rotary motor out tomorrow and see (and smell) if it has been fried...

This would explain why the sudden errors..

[Andy Fritz]

Hi Trebol,

I get the same error from time to time. It is always a blown fuse on the VH65.
Just stick a new one in and it works. I found that if I start the VMC with Emergency stop engaged, then release it and hit "Start" at the opening CS prompt the fuse blows. The work around is to instead hit "manual" to get rid of the prompt. Then release emergency stop, jog, and then manually do a CS.

BTW I am also using an AMC amp-0015 which is normally used for large motors but you can turn down the current limit pot to clip at 7 amps.

Cheers,

Andy

[Trebol]

Thanks Andy.
Appreciate your feedback.
Just as a matter of interest, could you please advise which pot adjusts the overall output of the amp card? Thanks.
Also how do you personally measure the output of the amp? Is it with a DC clamp meter while the axis is under load to check the max current draw for setting the output current?
Thanks again,
Cheers,
Tre.

[Andy Fritz]

Hi,

I dont really meassure the output. Each amp has a stated max amp rating and a current limit pot. For example;

AMC AMP-0015 is rated up to 20 amp, (peak i think), but for my small Glentek GM4020 rotary motor I only want 6 amps. On the Amp is a sticker which says; "GM4020 - Turn current limit pot 15 turns CW (max) and then 8 turns CCW". Thats it.

I just got a new aftermarket amp in which is said to run all dc motors. I have not yet tried it, but it has one RMS current pot and another Peak current limit pot where as all other amps I have seen only has one current limit pot.

If you want to be on the safe side, just turn down the CL pot more and then try a few rapid moves. Find the point where you get motor overload errors in rapid and then raise the CL a little from there until you can rapid with out errors.

Which amp do you have?

Andy

[Trebol]

Its a DC machine, and the Glentek AMP has 4568-4201 (C) on it.
A sticker says the model is GA4568EA-1HP.
This is on the A axis (VH65).

All the other AMP cards are 4568-4201 (E) 's.

The CL pot on this AMP only has one turn to adjust.

[Andy Fritz]

Ok they are all Glentek AMP-0021, so yes they are usually used for the large motors like GM6000 (20 amp). I have a few of those and tried checking resistance between some of the test points while playing with the CL pot. The problem is that I dont know which is the correct test point. There are three of them. All show some variance in resistance when moving the CL pot, but none show large enough resistance. I have a brand new amp from Fadal CNC and it has more test points. The instructions say that at the correct test point there should be 9.6 kohm when the CL pot is at highest i.e. set up for a 20 amp motor. If a 6 amp motor is used the CL pot should be set so there is a 5.2 kohm at the test point. I am sure these values dont translate to the AMP-0021, but the resistance closest was at test point 3 which gave 8,5 kohm with the CL pot fully CW and unfortunatly only dropped to 7,55 kohm which would suggest the current is clipped at around 10 amps.

Now the thing is I really dont know much about this so the above is just one of my ideas. I have been trying to get thorough info regarding tuning of amps and fault checking for a few years, but I think the one's who really know this stuff dont want to put the info on a forum as they make a living rebuilding amps.
Then there is a layer of service techs who dont really know all the ins and outs as they mostly just swap out troublesome amps for their customers.

In your case it is a very straight forward question though; What is the minium current when the CL pot is rock bottom? The AMC version of this amp is called AMP-0015 and it has a 15 turn CL pot and there is more happening between full CCW and full CW.

The new amp I installed this morning is cheaper than the Glenteks and is said to go from 0 - 20 amps. I am tuning it now. So far so good, but it remains to be seen how long it lasts. If it works ok I will likely replace the rest of the glenteks as they burn out. It is quite convenient to use only one type as you can nick the A amp when one of the others go bad as the A is not as vital as the other axis.

The Amp-0015 is also useable this way, but cost a few hundred US more.

Andy