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How do I fix an F11 (Output Phase Fault) code for a 9000X Series drive?

The output phase fault is looking for the loss of current draw or a significant difference in current draw on the output of the drive. The drive will look for this fault when it gets above .5Hz and the output current exceeds 2.5% of the high overload (VT) rating of the drive. It will get this fault if a phase is less than 1/8 the sum of all the filtered output currents. If this condition lasts for more than 2 seconds you will get an output phase loss. The first thing to do with this fault is disconnect the output of the drive and start the drive. If the drive faults on output phase loss there is something wrong with the current measurement on the output of the drive. If it does not fault, ramp the drive up to 60 Hz and check the voltage on the output of the drive. Normally, if the fault is coming from the drive it is because you are not firing one of the phases and you can see this by the voltage on the output. If you still do not see a problem run the drive on a test motor and check the 3 phase current on the output and compare that to the monitored value of all 3 phases. If this is all equal and everything looks good on a test motor hook the original motor back up and try this. If the drive trips right away you will need to use an oscilloscope on the output to be able to view the currents. If the currents are uneven at this point you will need to check the motor and its connections out.