What should be done if the pump motor's current exceeds full load current?

There are several reasons as to why the permitted full load current could be exceeded when operating the pump: Undervoltage, current imbalance in three-phase motors, motor has a short circuit, incorrect wiring or faulty electrical connections, viscosity or density of the pumped medium too high, or the pump is worn or blocked.

However, the pump may also be undersized for the application in question, and may be operating in excess of its nominal flow rate. In this case, try to partially close the shut-off valve on the pressure side in order to throttle the flow rate until the motor current returns to the acceptable limits.