PhaseShift
Senior Member
We were trying to start a 5hp motor today with a FLA of about 7A. The motor is a 480V six lead motor. As soon as the motor was started under load it would draw about 100A and then quickly trip the overload. This 100A seems extremely high for this motor
We then meggered the motor to find it was o.k. and uncoupled it from the load and found that we were able to spin the shaft by hand so that the motor wasn't binding. We then went ahead and started the motor uncoupled and saw the same results.
The motor nameplate was missing however we believe we found the correct datasheet and that the motor should be wired in Delta. However if the motor is supposed to be wired in wye, can having it wired in Delta cause this increased current that we are seeing?
What else could possibly be causing this if everything else mentioned above looks fine? We verified all motor connections and verified that the motor is not single phasing.
We then meggered the motor to find it was o.k. and uncoupled it from the load and found that we were able to spin the shaft by hand so that the motor wasn't binding. We then went ahead and started the motor uncoupled and saw the same results.
The motor nameplate was missing however we believe we found the correct datasheet and that the motor should be wired in Delta. However if the motor is supposed to be wired in wye, can having it wired in Delta cause this increased current that we are seeing?
What else could possibly be causing this if everything else mentioned above looks fine? We verified all motor connections and verified that the motor is not single phasing.