Input Undervoltage

What does Undervoltage mean?

This fault indicates that the incoming mains supply voltage has dropped below the VSD's minimum permissible operating threshold. This can be due to a brownout, a fault in the supply network, or incorrect sizing of supply components. Sustained undervoltage can cause erratic drive operation, reduce motor torque, and potentially damage internal power components if the drive attempts to compensate. It also prevents reliable operation.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Verify the capacity of the upstream power supply and distribution system to ensure it can support the VSD's demand.

2. 4

   Consult the power utility if widespread undervoltage or brownout conditions are suspected in the facility.