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Subject: Re: [CCHS] Electric Bikes
From: Clifford Heath <clifford.he...@gmail.com>
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On 11/04/2012, at 11:54 PM, Jarrod Tuma wrote:
> ... the transients are not so bad with most motors due to winding =
inductance.

Large inductance means you get fast voltage transients. Plan to mount
a small high-current inductor right at the switches so those steps don't
couple in elsewhere. Keep the return loops super-close, preferably on
the exact opposite side of the board. Twist all high-current wiring, =
etc=85
Don't forget about ground currents; ground is just the trampoline that
everything else bounces off.

> I doubt software is fast enough (assuming you meant braking, not =
breaking :)).
> software can be pretty quick ;)
> This is not a high-rpm motor, but yeah it could be a challenge.

The RPM isn't the issue. The braking effect is achieved in response to
the L/R time constants, not the RPM.

Clifford Heath