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Brian Whatcott
 
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On Mon, 16 May 2005 01:18:55 GMT, "Roger Long"
wrote:

It's a diesel boat.

Would you please explain the snubber business? I'm sure a lot of us
besides myself would like to know what it's for.



An inductive element like a relay coil or a motor stator or rotor
has a predictable reaction to suddenly cutting off the current through
it: a back voltage which can rise to a fast peak of hundreds of volts,
making a spark that jumps the opening contacts for a little while.

This wears the contacts out. And ignites gasoline vapor too.

If something is arranged to let the current through a coil fall more
slowly, the voltage rise is much lower. If some resistance is in
circuit, the energy stored in the coil is used by the resistance -
which heats up a little.
This combination of a capacitor and series resistor is called a
snubber, because it snubs (or damps out) the spark.
The cap and resistor is placed across the coil.

Make sense?

Brian Whatcott Altus, OK