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I am a tinkerer, you will have to excuse me as I am not well versed as most of the professionals here. I just have what I think is a simple question that I’ve looked everywhere for on the internet but I could not find a direct answer I could trust.

A little back story:

The victim of my electronic experiments is my little Razor dirt bike. Through the years (since I was twelve) I’ve upgraded every electronic part in the thing. I’ve learned a lot along the way. I’m now 18 and after not touching it for the last 2 or 3 years, I’ve just started to tinker with it a little.

If I use a three-way switch-over switch as a park-neutral-drive sort of thing, by shorting the motor terminals on one side of the switch, will this cause damage, such as demagnetization of the motor if it is only used at 0 RPM and left on for long periods? I’d prefer not to use any resistors as that adds a whole new level of complexity to my simple little idea.

I forgot to mention that the whole point of this idea is for when the bike is parked on a hill. I’ll just switch the switch to park and the motor will act as a parking brake.

Specifications:

  • 48 V, 10 Ah lithium-ion battery (built myself)
  • 48 V, 1800 W BLDC motor
  • 48 V, 1800 W cheap China controller
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  • \$\begingroup\$ Shorting the coil of a BLDC motor is fine as long as you've fully isolated it from the rest of the circuit. If it's still connected, we can't really know what will happen. A DPDT switch should be able to provide the necessary isolation (but don't throw the switch when the motor is spinning) \$\endgroup\$
    – Matt S
    Jan 25 at 15:44
  • \$\begingroup\$ (Though you might want to add a braking resistor instead of a dead short just in case the switch is thrown during motor operation) \$\endgroup\$
    – Matt S
    Jan 25 at 15:50
  • \$\begingroup\$ Maybe you can implement a slight modification that only allows the "short" should the terminal voltage be less than (say) 1 volt? \$\endgroup\$
    – Andy aka
    Jan 25 at 16:00
  • \$\begingroup\$ I like the idea of the switch not being allowed to activate unless the terminal voltage is less that 1 volt. How would I create something like that though? I should mention that the controller is non-programable. \$\endgroup\$
    – Johnny
    Jan 25 at 16:09
  • \$\begingroup\$ I'd be more worried about damage to the ESC in case you try to go forward while the brake is still on. \$\endgroup\$
    – user253751
    Jan 25 at 16:49

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