DB Resistor Overheat

What does RH mean?

The RH fault signifies that the dynamic braking (DB) resistor has overheated, detected when its duty cycle exceeds 3% as monitored by the inverter's software. This protection mechanism prevents damage to the resistor from excessive braking energy, causing the inverter to coast to a stop.

Complete Troubleshooting Guide

1. 1

   Evaluate the application's braking requirements; determine if the braking frequency or duration is exceeding the resistor's capacity.

2. 2

   Verify that the dynamic braking resistor is correctly sized and has adequate ventilation for its operating environment.

3. 3

   Inspect the resistor and its wiring for any damage, loose connections, or obstructions impeding airflow.

4. 4

   Review parameter L8-01 (Protection Selection for Internal DB Resistor) to ensure this protection is enabled for external resistors.

5. 5

   If applicable, consider adjusting deceleration times or installing a higher-capacity braking resistor.