What causes fault code 50002 (VFD Fault â€” Overvoltage)?

Deceleration time too short â€” regenerative voltage spike exceeds DC bus rating. Dynamic braking resistor open circuit or undersized for application. Incoming power voltage too high â€” check utility supply. Load has high inertia and is overdriving the motor during stop. Braking transistor in VFD failed â€” cannot dissipate regen energy

How do I fix fault code 50002?

Increase deceleration ramp time in VFD parameters â€” try doubling current setting. Check dynamic braking resistor â€” measure resistance with multimeter, verify wiring. Measure incoming AC voltage at VFD input terminals â€” should be within drive rating. Enable coast-to-stop mode for high-inertia loads if application allows it. Check VFD braking transistor output â€” consult drive manual for test procedure

VFD Fault â€” Overvoltage

50002

VFD DC bus voltage exceeded safe threshold, typically during deceleration when motor regenerates energy back to drive.

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vfd drive overvoltage braking deceleration

Probable Causes (ranked)

Deceleration time too short â€” regenerative voltage spike exceeds DC bus rating
Dynamic braking resistor open circuit or undersized for application
Incoming power voltage too high â€” check utility supply
Load has high inertia and is overdriving the motor during stop
Braking transistor in VFD failed â€” cannot dissipate regen energy

Fix Steps

1 Increase deceleration ramp time in VFD parameters â€” try doubling current setting
2 Check dynamic braking resistor â€” measure resistance with multimeter, verify wiring
3 Measure incoming AC voltage at VFD input terminals â€” should be within drive rating
4 Enable coast-to-stop mode for high-inertia loads if application allows it
5 Check VFD braking transistor output â€” consult drive manual for test procedure

Suggested Replacement Parts

Parts matched to fault category: Vfd Drive

Allen-Bradley PowerFlex 525 AC Drive 1HP P/N: 25B-D2P3N114 1HP, 480V, 3-phase, built-in EtherNet/IP, EMC filter

AutomationDirect $395.00 Amazon $450.00 Grainger $520.00

ABB ACS580 General Purpose Drive 2HP P/N: ACS580-01-05A7-4 2HP, 480V, built-in safe torque off, adaptive programming

AutomationDirect $425.00 Amazon $480.00 Grainger $550.00

GS20 AC Drive 1HP (Budget Option) P/N: GS20-20P5 1HP, 230V, sensorless vector, compact size — good replacement for testing

AutomationDirect $149.00 Amazon $175.00

Prices are estimates. Verify part numbers match your equipment before ordering.

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