Eaton Logo

How do I fix an F9 (Under Voltage Fault ) code for a 9000X Series drive?

The under voltage fault is taken from the DC bus (trip level is 183V for 230V drives, 333V for 480V drives and 461V for 575V drives). This fault will only occur if the drive is running when the DC bus gets to the trip level. This problem predominately is a loss of input power which the drive is running. This fault can be caused by an incorrect reading of the DC bus. This is easy to diagnose, as you can take a DC bus reading and compare this to the monitored value of the drive. If these readings aren’t really close to each other you may have a monitoring problem in the drive.