fightingrobots.co.uk

Hi All,

Matt of Team Plumb Crazy alerted me today about a potential safety hazard when using the Sidewinder with the Magmotor or other 4-brush motor with the Left and Right motor outputs connected to the brush pairs.

Basically the problem is in Brake mode at zero speed command it is possible to get a battery voltage across the windings of the motor. When connected with Left and Right Sidewinder outputs connected to the brush pairs.

This voltage will be at full battery voltage but running through the coils in a non-standard way so the motor may spin at 1/2 speed.

It is recommended that you run the Sidewinder only in Coast Mode or do not connect both motor outputs to a single motor unless you know the brush pairs are isolated.



Chris Baron
chris@robotpower.com
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Note, some older Sidewinders won't have Coast mode. They will be susceptible to this problem and without a mode to avoid it.

In that case do not connect the Sidewinder to a single motor using independent brush pairs with the Left and Right motor outputs.

There is no marking to tell. Basically if you got a set of three jumpers with your Sidewinder you have Coast available. If you got two jumpers it is probably not available without a software upgrade.



Chris Baron
chris@robotpower.com
Need Low Cost High Performance Speed Controllers?
Visit www.RobotPower.com and kick bot!


Want to try a different robotic sport? Check out

As much as I love using Sidewinders I'd never use them with Mags. But it's good information none the less.