Abnormal Output Current Detection

What does E.CDO mean?

The inverter output has been shut off because the output current exceeded the threshold set in Pr.150 Output current detection level. This protective function is only active when Pr.167 Output current detection operation selection is set to "1". It indicates an overcurrent condition that is monitored independently of the main overcurrent trip.

• Motor load experiencing mechanical binding or a jam, causing the motor to draw excessive current.
• Incorrect setting of Pr.150 (Output current detection level) set too low for the application's normal operating current or transient peaks.
• Inverter output phase loss (e.g., due to loose motor terminal, damaged cable, or motor contactor failure) leading to unbalanced currents.
• Motor insulation breakdown (phase-to-phase or phase-to-ground short circuit) causing a significant current draw.
• Inaccurate current sensor calibration or fault within the inverter's current measurement circuit.

Click steps to track your progress.

1. 1

   1. Measure actual motor operating current with a clamp meter and compare it against the inverter display and Pr.150.

2. 2

   2. Increase Pr.150 (Output current detection level) by 10-20% above the maximum normal operating current, ensuring it's still below the inverter's maximum output.

3. 3

   3. Inspect motor wiring for loose connections at the inverter output terminals (U, V, W) and the motor terminal box.

4. 4

   4. Perform motor winding resistance test (U-V, V-W, W-U) to detect phase-to-phase shorts (expected: balanced, low resistance) and insulation resistance test to ground (expected: > 1 MOhm).

5. 5

   5. Check for mechanical binding or obstruction in the driven load by manually rotating the motor shaft (if safe to do so).