[Bunya]

16i-MB control, ?i spindle drive, ?i-M motor encoder and a prox. switch for orientation driving a 2-speed gearbox. ?i-M motor encoder was replaced w/ new, gap set @ 0.004" and it's correctly reading the motor RPM. If i try to run the spindle I get a 31 (motor lock/v-sig loss) on the spindle amp, motor turns slowly one direction, reverses going even slower, then alarms out, the motor load jumps to 150% but I don't hear the motor loading down. In the Servo Tune page I'm getting the correct motor RPM, a spindle load, but spindle RPM stays @ 0. I have the HIGH/LOW gear selection simulated and it manually switches back and forth in the DSPOPR page, the relevant I/O is correctly changing in response, ladder 'knows' which gear it's in. Followed the data flow in the ladder as far as I could, PMC flips back and forth between reading the motor speed and motor load data from D1110 and sticks the speed data in D0520. That runs thru a multiply then divide operation using the gear ratio data as operands, then spits the spindle speed out to D0914 which I verified is correctly updating and changing based on LOW/HIGH gear status. I lose it from there, the only references to D0914 are in the speed calcs, I'm guessing it's doing a bulk memory transfer somewhere to pass it back to the CNC for display but I haven't been able to find it in the ladder. I've been going under the assumption that the 31 alarm is being caused by the spindle speed staying at 0. I haven't been able to determine if the motor speed or spindle speed reading is being used to generate the 31 alarm. I checked the IGBT modules in the drive, they all passed basic diode tests. I'm not sure where to go from here. If somebody can verify if the ?i-SP drives use motor speed directly or uses the spindle speed information to determine if the spindle is locked would help to focus me in the correct direction. I've run across several other posts with similar issues but none have any responses beyond parameters or sensor, both of which I've eliminated in this case.

Background

I'm resurrecting a Niigata HN-80D that was damaged by fire and declared a complete loss. I kept the control cabinet/servo motors to build a training / test stand. I'm using a couple of cheap microcontrollers and level converters as an easy to learn/understand, inexpensive PLC to simulate the missing bits like the pallet and tool changers, and whatever else that requires a response in the ladder. I got the 'virtual' pallet changer working well, but I can't test the ATC because the spindle isn't working. I have multiple backups of CNC & PMC parameters, SRAM images, etc. from when the machine was in production and the memory was never lost so I know all the parameters are correct. The original ?i-M motor encoder was bad, the foil had some scratch damage due to a failing bearing the the motor so it was replaced w/ new and the motor speed is now working. This is the ?i-M motor encoder without the Z (one rotation) signal, Niigata's using a prox. switch in the gearbox for Z info.

I greatly appreciate any help in figuring this out...

Marc --

[cncmakers001]

Motor lock or vector signal loss.
The drive cannot correctly detect rotation or motor vectors due to missing or invalid signals from the encoder.

[zavateandu]

Did you change by mistake 2 phases from the motor power cables on motor side or amplifier side?
for a correct sensor mount you need to hook up a osciloscope and see the sinusoid form for A and B signals