AB 1336E-CX300 strange problem

[Onil]

Have AB 1336E-CX300-ANENHA1. Motor not hookuped. No Faults or Allerts. Pushing Start button. Light CW ON. Light CCW blinking. RPM all time quickly jumping: +200; -10; +350; -100... etc. AC output voltage jumping 200; 50, 420; 5; 320... etc. What could be a problem?

[Ken Roach]

The 1336E is an IMPACT drive, one of the simplified FORCE drives, which use fairly sophisticated speed and torque controls that rely both on encoder feedback and on current feedback from the motor windings. I would not expect any predictable output from a Field-Oriented Vector Control drive if there is no motor attached. If you can place the drive into "V/Hz" mode (I'm not sure you can do that with the IMPACT drive) you could get a more predictable output because it's an open-loop system then. Why are you concerned with the voltage and frequency output with no load attached ?