Leakage fault

What does F89 mean?

This fault is triggered by a digital input fault, indicating an electrical leakage detected by an external monitoring device. This is a general leakage indication from an external system.

• Excessive earth leakage current detected by an external residual current monitoring device (e.g., RCM, RCD) on the input supply or motor output circuit.
• Damage to power cable insulation (input or motor cables) due to mechanical stress, chemical exposure, or rodent activity, creating a leakage path to ground.
• Breakdown of insulation in the motor windings or other connected equipment (e.g., braking resistor, input reactor), leading to current flowing to protective earth.
• Contamination by conductive dust, moisture, or chemical residues on busbars, terminals, or printed circuit boards within the drive or switchgear causing reduced insulation resistance.
• High frequency leakage currents from long shielded motor cables or EMI filters exceeding the trip threshold of a sensitive external leakage detection device.

Click steps to track your progress.

1. 1

   1. Isolate power to the entire system. Use a megohmmeter (e.g., 500VDC or 1000VDC) to measure insulation resistance from each phase conductor (L1, L2, L3 and U, V, W) to protective earth (PE) on both the input and output circuits.

2. 2

   2. Disconnect the motor from the drive. Measure insulation resistance between each motor phase (U, V, W) and the motor frame. Also check between phases.

3. 3

   3. Visually inspect all input power cables, motor power cables, and associated terminal blocks for any signs of damage, arcing, or excessive contamination (e.g., oil, water, conductive dust).

4. 4

   4. Check the wiring from the external leakage monitoring device to the drive's digital input (e.g., DI10). Verify the device's trip current setting and test its functionality if possible.

5. 5

   5. Use a clamp-on leakage current meter to measure actual earth leakage current on the input and output power cables during brief, controlled operation, if safe to do so.

6. 6

   6. Verify the integrity of the protective earthing system. Ensure all equipment frames are properly bonded to protective earth with low resistance connections (e.g., <1 Ohm).