Gentry loses all mastering

[Jim]

I encountered a problem with our gentry type robot (A1M, A1S1=X A2=Y A3=Z), , please help me with your advice.
After one or two minutes I get this message about drivers error and encoder cable failure. I checked the cables, connections, everything seems to be fine.
The strange thing is, it loses mastering on all axis in the same second.
Can a broken cable cause this? I swapped the RDC board (RDW2) with our other robot, but the problem remained, and the other robot works fine with that card.

The message:

1216      Ackn. DRIVERS ERROR A1 M No. TRIP
1216      Ackn. DRIVERS ERROR A1 S1 No. TRIP
1216      Ackn. DRIVERS ERROR A2 No. TRIP
1216      Ackn. DRIVERS ERROR A3 No. TRIP
106        Perform mastering A1
106        Perform mastering A2
106        Perform mastering A3
1204      Ackn. Encoder cable failure A1 M
1204      Ackn. Encoder cable failure A1 S1
1204      Ackn. Encoder cable failure A2
1204      Ackn. Encoder cable failure A3

Today I swapped the MFC card also, and now its only A1 S1 is problematic. What the heck is wrong?
It seems to be happening when axis Z is moving downward.
If I have to check a cable which one is to check out of 26? (I know most of them only for the read switches)
Please help...

[SkyeFire]

Every KUKA servo motor has two cables: the resolver cable (lots of little pins) and the power/brake cable (a few big pins).

Your first error suggests a problem with the main data cable (which runs from the RDC to the KRC cabinet), since all the axes lost mastering together.  But the new single-axis error suggests a problem with just that motor, possibly a short that was enough to cause the other axes to lose mastering the first time.

If the resolver cable for the problem axis undergoes flexion when the machine moves, I would look at that cable first, particularly at any spot where it bends.

All KUKA servo resolver cables are interchangeable, so you could also try swapping them around, as long as the lengths match up.

[Jim]

I have found the problem, it was a broken limit switch cable for the A1 axis. After I checked the encoder cables and everything was fine , I checked all the rest one by one removing them from the igus chain.
It took me four days but it's working now.
Thanks for the help