On Sat, 12 Jan 2008 06:13:16 +0000, John Rumm
wrote:

Sorry, what is a snubber circuit?

A circuit that helps dissipate the big spike of voltage that is
generated when you switch an inductive load. At its simplest it can be a
metal oxide varistor suppression type device (cheap at maplin).

If they are cheap, why don't the valve manufacturers fit them as
standard?