Annual inspection

Item

Inspection

Methods and tools

Expected results

Input / output circuitry insulation

Insulation between input/output terminals and earth terminal

Measure

Disconnect the Clean Power VFD and short R/S/T/U/V/W terminals, and then measure from each terminal to the ground terminal. Use a DC 500V insulation meter.

Must be above 5 MΩ

Input / output terminals

Tightening torque of all screw terminals.

Manual validation

Is there anything loose in the device?

All screw tightened at the specified torque.

Connections and cables

Are there any corroded cables?

Is there any damage to cable insulation?

Check cable for breakage and deterioration (crack, discoloration, etc.).

Visual

No abnormality

Terminal blocks

Check for damage.

Visual

No abnormality

Motor

Insulation resistance

Measure

Disconnect the cables for terminals U/V/W and test the wiring. Measure the insulation between U/V/W and the earth terminals with a DC 500V insulation meter.

Must be above 5 MΩ

Safety function STO (to be done for STO1 and STO2)

Check the power output

Turn off the main power supply of the Clean Power VFD and then on again.

Activate the STO function and the RUN function.

Connected test:

While the motor is running, activate the STO function.

STO alarm is displayed.

No voltage between U/V/W terminals.