What is the possible cause of NLP code in an ATV12 drive?
What is the possible cause of NLP code on an ATV12 drive?
ATV12 Altivar 12
Drive will not run it is tripped on NLP.
NLP means no line power or no line voltage. The drive thinks that there is no input voltage coming into the drive.
Check the and verify the line voltage on L1 L2 L3 of the drive. Go to the MON menu and check the ULn Mains voltage to see what the drive thinks the main voltage is.
Verify DC bus voltage on PA+ and PC- compare your DC bus voltage readings divide by the square root of 2 to see if it matches the Mains voltage in the MON ULn display.