Fanuc 11M Control - Torque Limitation Command Applied

Reading through the manual for our Fanuc AC Spindle Servo unit, being used with our Fanuc 11M controller, on a MOri Seiki MV35/40 VMC, there are two conditions occurring on our machine, which both refer to the 'Torque Limitation Command is Applied'. The conditions are no torque at the spindle i.e. when making a cut (even a light one) the spindle/cutter stalls in the workpiece, and the second one... the spindle is very slow to accelerate up to the assigned spindle speed.

Does anyone have a sense how to terminate this command? Is it done at the console or is there something on the VFD boards that needs to be tweeked. This is not a case of slipping belts... The monster is from the mid 80's, when I was knee high to a grasshopper. I am very comfortable dealing with modern VFDs, but this one is real dark ages to me. Trying to save us from the $140/hr repair call, just to be told we could have pressed the 'any key' to corr4ect it.

Any thoughts are very much appreciated as always!

The torque limiting command on the 6044 drive is on one of the inputs to the drive.
One for low speed and one for high speed. TLML is pin 5 and TLMH is on pin 21 of connector CN1 the common for both of them is pin 6. The control closes a switch to activate the function. I think they use this during gear changes.

The drive sends out confirmation of if it is in torque limiting on pins 9 and 10 on CN1. If those pins ring through. it is in torque limiting.
If they are open, something else is wrong.

The 6044 is a good drive. Its just great big.

You dont have belts on this mv35/40 do you?

The book I have for these drives is B-53425E/05

Did you check your ROM version? Table starts on page 9. I dont know if you just got this machine.

Thanks General.

It does indeed have belts from the AC servo motor to the spindle. I was told there is no rigid tapping, perhaps that is why?
Do you have the same machine?
I am just getting acquainted with it myself, but it has been in service for the last 37 years. The fellow who ran it the last 20 odd years just retired, so it's been left to use, a little worse for wear. We are trying to get it back to usable condition, since it would have to be chopped to pieces to get it out of the building, but more importantly it still holds a couple tenths at its ripe old age!

One other note, the actual rpm is no longer reading out on the console.

I have a mv40, no belts though. This drive was used for a long time by many builders.

I would have a look at the belts. Think Horse not Zebra.

Rigid tap was still a twinkle in an engineers eye when they were making these machines.

Are you sure it used to have actual rpm displayed? Spindle actual RPM display would come from something external to the drive. There is a speed display output from the screw terminals on the drive. But it is for the motor itself.