Functional path
Driver output
Turn-off diode path
Gate resistor / capacitor network
IGBT gate-emitter junction
Diagnostic signals and checkpoints
Driver-stage integrityDiode open-circuit conditionGate resistor damageReplacement module protection
Technician notes
- A diode in this path can require out-of-circuit confirmation because parallel resistance may disguise an open-circuit failure.
- This circuit deserves inspection whenever a power module failed or the repaired drive fails to produce output correctly.
Evidence intake
Turn this record into a qualified service request
A repair decision is much more reliable when the request includes the exact identity of the drive, the first fault evidence and the machine condition when the symptom appeared.
- Complete drive type code / MLFB or nameplate model
- Fault code, fault value and first event before reset
- When the event appears: power-up, enable, ramp, run, decel or stop
- Motor/cable connected or isolated during the symptom
- Visible board, option-card, module and connector identifiers
- Previous repair history, replacement parts and repeat-failure pattern