E.OC1 is a fault code displayed on Mitsubishi inverters (also known as Variable Frequency Drives or VFDs) that indicates an overcurrent condition. This means the current flowing through the output of the inverter to the motor has exceeded the safe operating limit.

Here's a breakdown of the E.OC1 fault on Mitsubishi inverters:

Cause:

Several factors can contribute to an E.OC1 fault:

• Motor overload: The motor connected to the inverter might be experiencing an overload condition due to excessive mechanical load, seizing, or binding. This can cause the motor to draw more current than the inverter can handle.
• Incorrect inverter settings: If the inverter's parameters, such as the current limit or motor capacity settings, are not configured correctly, it might not be able to handle the actual motor current, leading to an overload fault.
• Rapid acceleration/deceleration: Very rapid acceleration or deceleration settings on the inverter can cause temporary current spikes that exceed the limit, triggering the E.OC1 fault.
• Internal inverter issue (Less Likely): In rare cases, a malfunctioning component within the inverter itself could be causing the overcurrent condition.

Effects:

• The inverter will shut down to protect itself and the motor from damage caused by excessive current.
• The motor connected to the inverter will coast to a stop.
• An E.OC1 fault code will be displayed on the inverter's Human Interface Module (HIM) or keypad.

Troubleshooting:

Here's how to troubleshoot an E.OC1 fault on your Mitsubishi inverter:

1. Reduce Mechanical Load: If possible, check if the motor is experiencing any mechanical overload that might be causing it to draw excessive current. Reduce the load or address the mechanical issue if possible.
2. Verify Inverter Settings: Ensure the inverter's current limit and motor capacity settings are configured correctly for the specific motor being used. Refer to the inverter's user manual for proper configuration procedures.
3. Adjust Acceleration/Deceleration Settings: If you suspect rapid acceleration or deceleration settings might be causing current spikes, try adjusting them to a more gradual ramp-up and ramp-down profile.