Delta Inverter OVD Alarm (Overvoltage During Deceleration) – Causes & Solutions

Delta Inverter OVD Alarm (Overvoltage During Deceleration) – Causes & Solutions

During operation, if the DC bus voltage rises too high while decelerating, the inverter will trigger an OVD alarm (Over Voltage Deceleration). At this point, the inverter output is shut down immediately, the motor coasts freely, and the panel displays the OVD fault code.

Common Causes:

• Deceleration time too short, excessive regenerative energy

• Braking resistor/unit not installed or wired incorrectly

• Input power supply voltage too high or surge voltage present

• Motor grounding short circuit or control circuit interference

Effective Solutions:

1. Increase deceleration time (parameters 01-13, 01-15, 01-17, 01-19)

2. Enable overvoltage stall prevention function (parameter 06-01)

3. Use automatic acceleration/deceleration function (parameter 01-44)

4. Install or replace proper braking resistor/braking unit

5. Check input supply voltage and suppress surges with AC reactors if needed

6. Inspect motor cables and grounding to prevent short circuits

7. Optimize wiring and grounding to minimize interference

⚠️ Safety Note: Always power off the inverter and ensure the DC bus capacitors are fully discharged before making any parameter changes or wiring adjustments. If the problem persists, contact a qualified technician or Delta support.

By properly adjusting parameters and configuring the hardware, OVD alarms can be effectively resolved, ensuring reliable and long-term operation of the inverter.