Brake Resistor Short-Circuited

What does 25 mean?

The connected braking resistor has been detected as short-circuited. This prevents proper energy dissipation during braking, potentially damaging the drive's braking chopper or causing overvoltage trips during deceleration.

• Internal winding short circuit within the braking resistor due to thermal stress or aging.
• Short circuit in the wiring connecting the braking resistor to the drive's terminals (e.g., R+ and R-).
• Moisture ingress or conductive foreign material bridging the braking resistor terminals.
• Incorrect selection or faulty internal connection of the braking resistor enclosure.

Click steps to track your progress.

1. 1

   1. Power off the drive and disconnect the braking resistor wiring from the drive's terminals (e.g., R+ and R-).

2. 2

   2. Measure the resistance across the braking resistor terminals using a multimeter. Compare the reading to the nominal resistance specified (e.g., 20 Ohms). A near-zero reading indicates a short.

3. 3

   3. Visually inspect the resistor wiring for damaged insulation, frayed conductors, or accidental bridging between conductors.

4. 4

   4. Check the resistor terminals and enclosure for conductive dust, metal shavings, or moisture that could cause a short.

5. 5

   5. Replace the braking resistor unit if the measured resistance is significantly below its specified nominal value, indicating an internal short circuit.