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Unread 26-01-2006, 16:28
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Re: Is Back EMF Safe for Victors?

Quote:
Originally Posted by Tom Bottiglieri
When a motor is backdriven, it becomes a generator and creates a voltage across its input terminals. This is called Back EMF, and the voltage produced is proportional to the angular velocity of the output shaft.

Does anyone know if creating this Back EMF will damage a powered Victor speed controller? And if so, what is the max amount of current that can be "backdriven" into a Victor without damaging the electical components?

In laymens terms... Can I set a Victor to coast mode, hook up a CIM motor to it, turn the bot on, backdrive it at 5000 RPM and live to tell about it?
The back-EMF that a CIM develops at 5000 RPM is just under 12 Volts. That voltage will not damage a Victor.

Backdriving at much faster speeds could create a problem, but you'd need to analyze the particular loading conditions. In general, backdriving above the 12 Volt free-speed of any motor will create the potential for it to regenerate back into the 12 Volt supply (battery), and extreme regeneration can overload circuit elements just as extreme motor loading can.

Someone at IFI may be able to comment on regenerative capability of Victors.
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