Input line supervision

What does 10 mean?

The drive has detected a missing phase in the incoming AC supply voltage. This typically indicates a power supply issue, such as a blown input fuse, a tripped circuit breaker, or a disconnected supply cable. Operating the drive with a missing input phase can lead to internal damage, particularly to the input rectifier bridge.

• Blown fuse or tripped circuit breaker on one or more phases of the incoming AC supply to the drive.
• Loose or disconnected wiring on one phase at the drive input terminals (L1, L2, L3), input contactor, or upstream breaker.
• Faulty main contactor where one or more contacts fail to close, preventing full three-phase power.
• Imbalance in the incoming AC supply voltage, with one phase significantly lower than the others.
• Malfunction of the drive's internal phase detection circuit.

Click steps to track your progress.

1. 1

   Measure the incoming AC line-to-line voltages (L1-L2, L2-L3, L3-L1) at the drive input terminals using a true RMS multimeter, ensuring all three are present and balanced.

2. 2

   Verify continuity of all input fuses or proper operation of input circuit breakers upstream of the drive using a multimeter.

3. 3

   Inspect the wiring connections at the drive input terminals (L1, L2, L3), main contactor, and input disconnect switch for tightness and integrity.

4. 4

   Check the state of the main input contactor (if used) by observing its auxiliary contacts or measuring voltage across its main power contacts when energized.

5. 5

   Disable the input phase supervision parameter (e.g., P7-03 to "0") for testing purposes only, if allowed by application, to confirm the fault source is external.