Industrial Engineer · phase 8 of 16
Braking Chopper
Electronic switch that connects a braking resistor to the DC bus when bus voltage rises during deceleration.
The Explain card
- Plain English
- The braking chopper is a switch inside or beside the drive that connects a braking resistor across the DC bus when the bus voltage climbs too high. It turns excess energy into heat.
- Example
- A loaded conveyor decelerates quickly and the motor becomes a generator. The bus rises, the chopper fires, and the resistor on top of the cabinet glows instead of the drive tripping.
- Why it matters
- Without a chopper, any fast deceleration of a high inertia load ends in an overvoltage fault. The chopper needs a resistor sized for the energy and the duty cycle, and a resistor that runs too hot is a fire on the cabinet roof.
- Hook
- The place to throw energy the motor is giving back.
Where it sits in the deck
Phase 8: VFD Drive Hardware and Power Path
Inside the drive: rectifier, DC bus and inverter, the three stages every variable frequency drive uses to rebuild the waveform a motor sees.
