Scope of this technical record
Functional brake-chopper area used in deceleration overvoltage, brake resistor and regenerative energy cases.
Brake chopper and resistor circuits are tied to the DC link and can be hot or energized. Follow rated braking procedures.
Brake-chopper board evidence route
The brake area must be judged with resistor value, wiring and machine duty cycle.
Brake-chopper board evidence image
What to document on the brake path
A useful brake-chopper submission shows whether the drive uses an internal chopper, an external braking unit or no braking hardware. The evidence should include resistor value, thermal contact, terminals, chopper transistor area and whether the resistor ever warms during a deceleration event.
Brake board evidence table
The table separates missing braking capacity from damaged chopper hardware or DC-bus feedback problems.
Brake-chopper board evidence
| Area | Why it matters | Evidence |
|---|---|---|
| Brake transistor | Switches bus energy | Short/open/driver area evidence |
| Resistor terminals | Common wiring failure | Terminal photos and resistance |
| Thermal contact | Can disable braking | Thermal input wiring |
| Bus feedback | Determines switch threshold | Feedback divider area |
| Duty cycle | Resistor overheating | Machine stop frequency and load |
Field record checklist
- Internal/external brake type
- Resistor value and rating
- Thermal contact status
- Chopper transistor area
- Bus feedback evidence
- Load and stop frequency
Technical basis and reference documents
This is an independent editorial technical reference. Original manufacturer documentation remains controlling for installation, repair and commissioning decisions.
Circuit path for this board area.
Linked circuit records
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