Short circuit

What does 16 mean?

A direct short circuit condition has been detected either within the motor's windings or across its terminal connections. This is a highly critical fault that triggers a trip-lock, requiring a power cycle to reset after the cause is rectified. Operating with a short circuit can cause immediate and irreparable damage to the frequency converter's IGBTs or other power components.

• Direct phase-to-phase short circuit within the motor windings due to insulation failure.
• Loose strands of conductor or foreign metallic objects causing a short circuit at the motor terminal block.
• Severe damage to motor cable insulation, leading to direct conductor-to-conductor contact (phase-to-phase short).
• Drive internal power component (IGBT) failure on the output stage, resulting in a permanent short.
• Incorrect wiring in the motor terminal box, causing a misconnection (e.g., two phases directly connected).

Click steps to track your progress.

1. 1

   Power off the drive and disconnect input power. Disconnect motor cables from drive output terminals (U, V, W).

2. 2

   Measure resistance between each pair of motor phase terminals (U-V, V-W, W-U) at the motor. All three readings should be similar and low (e.g., < 1 Ohm for large motors).

3. 3

   Visually inspect the motor terminal box for loose wires, metallic debris, or damaged insulation between phases.

4. 4

   Perform an insulation resistance test (megger) phase-to-phase and phase-to-ground on the motor windings.

5. 5

   If motor and cable tests are clear, a drive internal fault is likely. Contact authorized service personnel for internal diagnosis.