Brake Resistor Short-Circuited
Danfoss · VLT HVAC Drive FC 102
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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.
Vanlige årsaker
- 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.
Reparasjonssteg & Sjekkliste
Klikk på steg for å spore fremgangen.
- 1
1. Power off the drive and disconnect the braking resistor wiring from the drive's terminals (e.g., R+ and R-).
- 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. Visually inspect the resistor wiring for damaged insulation, frayed conductors, or accidental bridging between conductors.
- 4
4. Check the resistor terminals and enclosure for conductive dust, metal shavings, or moisture that could cause a short.
- 5
5. Replace the braking resistor unit if the measured resistance is significantly below its specified nominal value, indicating an internal short circuit.