Braking resistor

Braking Resistor is, as it's name suggests, a general-purpose braking resistor primarily intended for handling regenerative power from low to mid-power servo and stepper-motor drives.

An external high-power shunt resistor is switched on, drainging power from the bus when the bus voltage exceeds some limit $V_{bus,high}$, and kept on for at least $t_{min}$ and until the bus voltage falls below $V_{bus,low}$.

Braking Resistor can be used with bus voltages ranging from 12 V to 75 V, and can sustain an average load of 8 A, or 35 A at a 5% duty cycle with 1 ms pulses, with the default pass transistor. Other transistor choices allow operation at up to 300 V and significantly higher currents.

This entire project is open source hardware and made available under the terms specified in each file. Commercial solutions are available upon request, see Desel.

Braking Resistor documentation V1.0.0

Braking Resistor V1.0 Gerber files

Braking Resistor V1.0 Eagle project