11
Output phase supervision
Vacon · NXP/C
What does 11 mean?
The current measurement system has detected that there is no current flowing in one of the motor phases. This typically indicates an open circuit condition in the motor cables or within the motor windings, which can lead to motor damage or uncontrolled operation.
Common Causes
- One or more output phases are open or shorted.
- Uneven phase current distribution (P1-04, P1-05).
- Faulty output transistors (IGBTs) in the inverter stage.
- Motor winding insulation breakdown.
- Incorrect motor connection to output terminals.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Check all physical connections and the integrity of the motor cables between the frequency converter's output terminals (U, V, W) and the motor's input terminals.
- 2
Perform a winding resistance test on the motor phases (U-V, V-W, U-W) to check for open circuits or abnormally high resistance windings.
- 3
Perform an insulation resistance test (megger test) between each motor phase and the motor frame to check for ground faults.
Verified technical data. Last updated: March 2026
Related Faults
Source: Vacon NXP/C