The “P-LOSS” message indicates that an input phase is missing or has low voltage. Check the incoming power supply connections, are tightened correctly with the specified torque.
Measure the phase voltages, and ensure they are within the allowed operating range of the drive.
Confirm the voltage levels are balanced across the phases.
Ensure that one phase does not reduce in voltage when the drive operates under load, which would indicate a poor connection or contact in the drive supply line..