Overcurrent During Acceleration
Mitsubishi Electric · Mitsubishi FR-E800 Variable Frequency Drive
What does E.OC1 mean?
When the inverter's output current rapidly increases to approximately 230% of the rated current during the acceleration phase, the internal protection circuit is triggered, leading to an immediate shutdown of the inverter output. This can indicate excessive load, improper acceleration settings, or an output short-circuit condition. Left unaddressed, this can cause repeated trips, motor damage, or inverter component stress.
Additional Steps
Steps 1–2 are listed in Priority Fix.
- 3
Verify the motor and inverter capacities are matched and adjust Pr.3 (Base frequency) if needed (e.g., 50Hz for 50Hz motor).
- 4
Lower the stall prevention operation level or activate the fast-response current limit function.
- 5
Confirm encoder and motor wiring/specifications are correct, especially when using Vector control.