Overcurrent

Hva betyr OCF ?

This fault indicates that the current drawn by the motor has exceeded the drive's maximum permissible limit. Common causes include incorrect drive or motor parameters, excessive mechanical load, or a mechanical locking of the driven equipment. An overcurrent condition can quickly damage both the motor windings and the drive's output power stage (IGBTs).

• Excessive mechanical load on the motor (e.g., jammed conveyor, seized bearing, binding mechanism).
• Incorrect motor nameplate parameters entered in the drive (e.g., P0-02 Rated Voltage, P0-03 Rated Current).
• Short circuit in the motor windings (e.g., phase-to-phase, phase-to-ground) or motor cable.
• Drive output phase imbalance due to internal IGBT failure or damaged output filter components.
• Too short acceleration ramp time (e.g., Parameter P1-03) for the connected load and motor inertia.
• Faulty internal current sensor within the drive providing an inaccurate measurement.

Klikk på steg for å spore fremgangen.

1. 1

   1. Disconnect the motor from the load and check if the motor shaft can rotate freely by hand.

2. 2

   2. Verify all motor nameplate data (e.g., P0-02, P0-03, P0-04, P0-05) are accurately entered in the drive parameters.

3. 3

   3. Perform a motor insulation resistance test (Megger test) on motor windings and motor cable for shorts.

4. 4

   4. Increase the acceleration ramp time (e.g., Parameter P1-03) to reduce the initial current surge.

5. 5

   5. Measure output currents on all three phases (U, V, W) using a clamp meter during startup to check for imbalance.

6. 6

   6. Temporarily reduce the maximum current limit (e.g., Parameter P1-54) to see if the fault can be avoided (for testing only).