[Trebol]

Hi there.

Recently had an issue with a DC FADAL 3016 where the X axis (Glenteck) started to become rough. I took the machine apart and checked the table and it moves freely.

Seemingly it could be the motor that was causing the issue as with every rotation there would be a slight judder at the same position. I took the motor apart and cleaned up the comutators (main and tach) and checked the brushes. The tip of one of the brushes on the tach was cracked so it was removed and replaced.

The motor was run for a while outside the machine on a 12v computer transformer and ran well. After putting everything back together, on start up the maching spins the x axis for an instant then gives error codes of:
(1) Motor Overload and
(2) #3 error (a possible tach issue). After pushing "jog" to reset the axis' the same errors pop up and the machine goes into E-stop.

I had a thought that maybe either the tach or the resolver was on the way out previously, hence the rough running (or maybe hunting) earlier and I'm guessing that the subsequent error messages may confirm this.

As a final check to eliminate any other prossibilities, I interchanged Y axis cards (amp and controller) with the X axis, and the fault stayed with the X axis motor, hence the problem should NOT be in the electronics.

I also connected the motor to the lathe and ran it at RPM's ranging from 70 to 750 whilst measing tach output. Using 7v per 1000RPM (reference Maintainance manual) in each instance (and assuming lathe RPM is relatively close to the mark) the tach output voltage was 7-8% overreading.

Fully assuming the the motor/tach or resolver is at fault here, I have sent the motor off to a servo motor repair place to test out and repair if needed.

So I'm wondering if anyone else has had simular symptoms and whether it was a tach or resolver issue?

Very interested to hear any thoughs...

Thanks,
Tre.

[alex gitzel]

try swapping the wires around,normal is red-red and black-black on the power side and black-shield and black-red to the tach but it can be any combo,try the tach first then the power wires.this is a very common issue when installing a motor.otherwise something may be wrong with the resolver the plugs are touchy sometimes make sure the pins are all tight.