Toshiba VS-11 motor over load parameter

We have 1 odd ball inverter in the plant and its a Toshiba VS-11 and it is startin to fault out on error OC3. The manual says over current.

I can find in the manual where the over load setting is. A/B is easier for me but being as we only have 1 of these I am not used to them.

Can some one guide me in the right direction?

Thanks

First, overload fault and overcurrent fault are not the same thing. Overload fault is the drive's motor thermal protection calculations identifying the estimated temperature of the motor to be excessive. Overcurrent fault is the drive protecting ITSELF. It is seeing either continuous output amps or shortterm overcurrent amps in excess of its rating. The overage is not so high as to cause an output short circuit fault but is simply above the drive ratings and will lead to drive overheating or failure if not corrected.

Usually, this fault occurs during startup or acceleration periods where the shortterm rating is exceeded.

oc1: Over-current during acceleration
oc2: Over-current during deceleration
oc3: Over-current during constant speed operation
ocl: Over-current in load at startup
oca: Short circuit in arm
ol1: Over-LOAD in Inverter
ol2: Over-LOAD in motor
oh: Overheat trip

I suspect a problem with your load. Bad bearings, etc. VFD and motor may be okay.

Thanks, but I know what the error codes mean, I just need to know what parameters to check to see if there correct.

Mainly F415. See page 64 here, or page K-15 here.

bright676 said:

Thanks, but I know what the error codes mean, I just need to know what parameters to check to see if there correct.

Click to expand...

I'm not sure you do know what it means, because your title says "motor overload" and as DickDV and keithkyll explained, that is NOT what OC3 means.

If nobody has been changing parameters in the drive and it starts tripping on OC, 9 times out of 10 that means something has changed on the LOAD side of the drive. Either there is some brief sharp spike in torque requirement at the motor shaft, or something is going on inside of the motor. If nothing about the machine or load has changed, it's the motor.

In my experience, assuming this is an "experienced" drive installation, your motor windings are experiencing turn-to-turn shorts as the insulation begins to fail, the likely result of nobody paying attention to the possibility of standing wave spike generation in the drive-to-motor circuit and/or not using an inverter rated motor (or using a cheap one that just says the words). This will only continue to get worse. You will likely need to replace or rewind the motor. A phase to ground megger test would not detect this condition, you need to do a phase to phase test if you want to be sure.

Thats why I needed to know what parameter to check, to see if it has changed.