[cobiecat]

Hello,

I've got four old Parker APEX 604-MO servo motors in near perfect unused condition. I'm trying to get one of them working with a Parker Gemini GV-H20R drive. I'm getting some strange behavior in Auto Run mode DMODE 13. The motor shaft is supposed to turn at about 1 rev/second with the resolver counts being positive and increasing. The counts can be monitored with the TPE command. The shaft does turn in the clockwise direction, but the counts are negative and increasingly negative instead of being positive and increasing. The motor shaft also tends to shutter or cog for a few revs before becoming smoother. Sometimes the shaft will actually start in the CCW direction before reversing to CW direction. There are no drive faults, and I'm pretty sure I have the motor parameters set correctly in the drive.

I'm thinking that I just don't have the drive feedback cable wires connected to the proper pins on the motor connector. The APEX motor guide does not have the pinout for the feedback connector for some reason. Parker sells a Gemini to APEX cable set, but they cost a fortune, so I've made my own up. The drawing for the Gemini to APEX resolver cable doesn't seem to be available for some unknown reason, even though I have the Parker part number for it. The only thing I could find was a connection diagram for using the APEX motor with an APEX drive (I don't have an APEX drive). I was able to Ohm-out the pins to determine the two sets with equal resistance (SIN/COS) and the REF (rotor) pins with higher resistance.

Attached is a photo of the connector, which reflects the wiring I'm using to the Gemini feedback connector. The pinout is probably not quite correct as marked. The U and T pins are the motor temperature switch connections.

Can someone tell me the typical symptoms of reversing the sin / cos connections by accident, and also how not having the correct +/- polarity might screw things up.

I'm not very knowledgeable about this sort of stuff, and don't have an oscilloscope or other test equipment.

Thanks in Advance
Mark

[spumco]

I couldn't find anything exactly on target, but this might help:

https://community.parker.com/technol...n-1-connection

Also, there's a note on the Parker site which states that the "Z" motor is the same as the Apex. That might help during research.

Another option is to replace the resolvers w/commutation encoders. The Gemini series drives can use encoders, including the -R models.