VFD Not Powering Up (Public)

If a VFD display is blank or will not turn on, confirm the following:

1. Verify that the breaker is turned on.

2. Ensure that the breaker is properly sized for the fan.

3. Confirm that the wire gauge is appropriate for the voltage, load, and length of the wire.

4. Verify that the voltage being provided is within the drive's rated input power.

5. Ensure that the disconnect switch is properly assembled (if present).

6. Confirm that the disconnect switch is on (if present)

7. Test the fuses (if present).

8. Verify that the VFD is wired correctly using the VFD wiring diagrams located in the installation manuals here.

9. Ensure that voltage is present directly on the VFD input terminals. If there is voltage, and the VFD is Schneider, proceed to step 11. If there is no voltage, proceed to step 10.

10. Check for voltage at every termination until you find where it is being stopped. Inside of the VFD control panel (excluding AVD370, AVD3, and AVD5), voltage can be verified at the following spots:

• On top of the disconnect
• On the bottom of the disconnect
• On top of the fuse holder
• On the bottom of the fuse holder

11. (Schneider only) Confirm that the ribbon cables inside of the VFD are plugged in (instructions here).