> for the inductive snubber I was using a 30V 5W zener across
> the drain & source

In motor drives and for SMPS inductors I've always seen, and used,
a power Schottky, as it's meant to conduct before the body diode.
A large zener is comparitively slow because of its capacitance.

The place I'd put a zener (generally 12 or 15V 0.5W in a 12V system)
is g to s

Typically the Schottky might be something like an STPS1545, where
'15' is the amperage and '45' is the voltage. Manufacturer prefix varies,
eg MBR, MBRB etc

STSP1545

http://www.st.com/web/en/resource/technical/document/datasheet/CD00000819.p=
df

On a couple of occassions I've had to add an ultrafast power diode,
(eg MURxxx, BYVxx), and an RC snubber at the motor terminals
to clean up some of the hash

Joe=20



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