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Can stepper motor use electrical braking? I think I can stop a running stepper motor more quickly with an electrical braking resistor. Is this feature popular among stepper motor controllers? I am a little confused that most manuals of stepper motor driver don't say about electrical braking resistor or other electrical braking method.

(I know electrical braking is popular in inverters for AC motor, like brake resistor or DC braking in Omron inverter)

Thank you.

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  • \$\begingroup\$ A resistor won't give you any more braking torque than actively driving the coils in the usual fashion will. The maximum electrical torque of the motor is what it is; if the load on the shaft exceeds this value (accelerating or decelerating), the motor will "slip". \$\endgroup\$
    – Dave Tweed
    Commented Aug 19, 2014 at 15:10
  • \$\begingroup\$ @DaveTweed: An advantage of using a passive braking approach is that the motor will always resist motion; by contrast, when driving the coils in the usual fashion, once the motor has rotated past the current "step", the current driven into the coils will try to push the rotor ahead toward the next step. That having been said, if the goal is simply to stop the motor as quickly as possible, I would think that dead-shorting the leads together would be as effective as using a resistor. \$\endgroup\$
    – supercat
    Commented Aug 19, 2014 at 15:19
  • \$\begingroup\$ @supercat: Valid point, but that isn't what the OP is asking. He wants to brake as quickly as possible, not as smoothly as possible. Active drive will always be able provide more torque (current) than back-EMF alone. \$\endgroup\$
    – Dave Tweed
    Commented Aug 19, 2014 at 16:10
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    \$\begingroup\$ @DaveTweed: Active drive will provide more torque, but in the absence of positional feedback that torque won't always be in the right direction. If the motor is turning rapidly, the torque in the wrong direction may cancel out much of the effect of torque that would be in the right direction. \$\endgroup\$
    – supercat
    Commented Aug 19, 2014 at 16:43
  • \$\begingroup\$ @supercat: You're arguing in circles. If the torque is in the "wrong direction", then you either aren't driving the motor correctly, or the system has exceeded the torque capability of the motor, and the motor has "slipped" (lost sync with the drive circuit). \$\endgroup\$
    – Dave Tweed
    Commented Aug 20, 2014 at 17:53

2 Answers 2

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No for 'typical' use, especially when use with standard IC chip, like TB6560, which you sent a step-pulse and direction signal and it does the rest automatically, data sheet. The chip automatically provide a reduced holding current, as section 5 in data sheet, to maintain holding torque and shaft at sub-degree accuracy, once motor is stopped. Holding torque and sub-degree shaft accuracy is one of the advantage of stepper.

In 'typical use' stepper is locked so that it trace out a precise profile, like page 14 of data sheet for micro stepping, as used in floppy disk drive, many industrial CNC machines and 3D printer 3D printer stepper software

Of course, one can open circuit the coil or short circuit the coil, if needed.

Stepper motor work on different principle than brushed DC motor.

Stepper normally maintain locking on each step and, by nature, lock is breaked.

To decelerate steppe motor, adjust pulsing frequency in a downward trend s to gradually slow down the stepper to zero speed.

speed profile over time

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    \$\begingroup\$ I've seen stepper motors that can freewheel, and only lock when a phase is shorted. \$\endgroup\$
    – Ignacio Vazquez-Abrams
    Commented Aug 19, 2014 at 15:41
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Normal, non-freewheeling, stepper motors generally require no braking... especially if they're used to drive a mechanism with high mechanical advantage.

BUT... any stepper motor CAN be forced to a stop by short-circuiting the leads together, in pairs. That must be done VERY carefully (see below), only when NO power is being supplied to the motor by its driver.

Circuit and/or software design must be done very carefully to ensure that short-circuit braking never occurs while the motor is still under power - even a momentary short-circuit for braking purposes may destroy the driver electronics.

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  • \$\begingroup\$ I could understand "That must be done when NO power is being supplied to the motor by its driver." What does "That must be done VERY carefully, ..." refer to? It seems redundant unless there is some other piece of information which you haven't included in your answer. \$\endgroup\$
    – gbulmer
    Commented Aug 19, 2014 at 18:44
  • \$\begingroup\$ It probably could stand some clarification - circuit and/or software design must be done very carefully to ensure that short-circuit braking never occurs while the motor is still under power - even a momentary short-circuit for braking purposes may destroy the driver electronics. \$\endgroup\$
    – TDHofstetter
    Commented Aug 19, 2014 at 19:13
  • \$\begingroup\$ You could update your answer with that comment. \$\endgroup\$
    – gbulmer
    Commented Aug 20, 2014 at 11:00

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