In article , "Dave Plowman (News)"
writes:

In article ,
Mike Fleming wrote:
In article , "Dave Plowman (News)"
writes:

Got a switch story from my old car. The window switches control relays.
The exact same Lucas switch is used on other makes with no relays. On
mine, the switches need regular cleaning. In the high power use, not.

When switching relays, presumably it's breaking the supply to a
reactive load?

Yes - although with only about 100mA flowing, not enough of a spark to
keep them clean.

I was thinking of the high voltage arc as the field collapses causing
damage to the contacts.

--
Mike Fleming