Air compresser

When pressure get's near 30 lb, motor starts to drag and then kicks the motor out. it is a 60 gallon, 7hp motor

_________________________
Bill says...

As air is compressed into the compressor tank, the pressure, obviously, builds up.

As that pressure builds, the electric motor has to work harder to drive air into the tank. They are built to handle this increasing load.

In your case, your motor is lugging because (I suspect) the load is building to the point where the motor cannot overcome it.

You haven't given me enough details to try to help determine why this is happening on your compressor.

Dump all air, disconnect the power, and pull the check valve to make sure it's working OK. See the check valve info page linked from the valves page.

Make sure there is no restriction on the intake (plugged filter or valve not opening).

Assuming that the compressor pump is working properly, the next check is the motor. If you can't test it, take it to an electric motor rebuild shop and ask them to.

Good luck,

Bill