Direct Ground Short-Circuit (Hard Detection)

What does SCF3 mean?

A hard detection of a direct ground short-circuit. This indicates a severe fault where a motor phase or internal component is directly shorted to earth ground. This condition poses a significant safety hazard and can cause severe damage to the drive. This fault can be manually cleared if the 'Reset restricted fault configuration' (HrFC) parameter is set to 'Yes'.

• Motor phase wire directly shorted to the motor frame or earth ground due to insulation failure.
• Internal wiring within the drive or motor starter shorted directly to chassis ground.
• Significant water ingress or conductive foreign material bridging a phase conductor to ground.
• Damaged motor cable insulation causing a direct short from a phase conductor to conduit or machine frame.

Click steps to track your progress.

1. 1

   1. Disconnect all motor phases (U, V, W) from the drive output terminals.

2. 2

   2. Use a megohmmeter to measure insulation resistance from each motor phase (U, V, W) to the motor frame ground (PE).

3. 3

   3. Visually inspect the motor terminal box for moisture, debris, or damaged wire insulation.

4. 4

   4. Inspect the entire length of the motor cable for insulation damage, pinch points, or water ingress.

5. 5

   5. If the motor and cable test clear, power down and check for internal drive wiring shorting to its chassis.