Output Open-Phase

Hva betyr LF ?

An open-phase condition has been detected at the Drive's output, where the output current imbalance exceeds 5% (L8-07=1 enabled). This is commonly caused by a broken wire in the motor cable, a broken winding in the motor, or loose output terminal connections. Operating with an open phase can cause motor damage due to imbalanced currents and vibrations, as well as reduced performance.

• Broken conductor within the motor cable preventing current flow to one phase.
• Loose or corroded connection at the Drive output terminal (U, V, W) or motor terminal box.
• Internal motor winding open circuit (e.g., one phase coil broken).
• Blown fuse in one phase of the motor protection circuit (if external fuses are used).
• Improper Drive output contactor operation, preventing one phase from closing.

Klikk på steg for å spore fremgangen.

1. 1

   1. Power down the Drive. Disconnect the motor leads from the Drive output terminals (U, V, W).

2. 2

   2. Using a multimeter, measure the resistance between motor phases U-V, V-W, and W-U. Look for an open circuit (infinite resistance) or significantly imbalanced readings.

3. 3

   3. Check all motor cable connections at both the Drive output terminals and the motor terminal box for tightness and signs of corrosion.

4. 4

   4. Verify parameter L8-07 (Output Open-Phase Detection) is set to '1' (enabled) for reliable detection.

5. 5

   5. If resistance readings are normal, inspect for external motor fuses and test their continuity with a multimeter.