Industrial Engineer · phase 14 of 16
Output Phase Loss
Detected open motor phase or severe output-current imbalance between phases.
The Explain card
- Plain English
- Output phase loss means one motor lead is open or the current in the three phases is badly unbalanced. The drive is trying to run a three phase motor on two.
- Example
- A motor terminal works loose and one phase drops out. The motor hums, draws high current on the other two phases, and the drive trips on output phase loss.
- Why it matters
- A motor single phasing overheats fast, so the trip saves the winding. The cause is nearly always a connection, a contactor, or a broken conductor, and the drive is telling you which side of itself to look on.
- Hook
- The motor is running on two legs and the drive knows it.
Where it sits in the deck
Phase 14: VFD Safety, Faults, and Diagnostics
What a drive does when it trips, what the fault codes are telling you, and how safe torque off stops the motor without killing the panel.
