"Kelly E Jones" wrote in message
...
In article nZZec.123791$gA5.1527613@attbi_s03,
Tweetldee wrote:

Relays used to switch inductive loads, such as your pump motor, are prone
to
arcing when they switch on and off. This is quite normal, and unless
some
sort of arc suppression (snubber circuit) has been used across the
contacts,
they will eventually fail.

Can I buy a snubber somewhere? Can I build one with a few parts from
RadioShack?

BTW, it seems most people switch their pumps with a pressure switch (as
opposed to a relay), and I've never seen a snubber on a pressure
switch.

Kelly


A snubber is simply a series resistor-capacitor connected dierctly across
the contacts. Usual values are 47 ohms and 0.005 uF. I've seen a few
relays with MOVs across the contacts. You might try either, or both. The
trick is to keep the RC from being burned to a crisp when lightning strikes
nearby. I tried that combo on a pressure switch on a pump, but living in
FLA, the lightning capitol of the world, it turned out to be more trouble
than it was worth. Was having to replace the RC every week or so during the
summer months when afternoon storms blew through the area.
I finally abandoned the idea and just left the switch contacts alone. Never
had any trouble from them aside from the pitting and sticking, which is
quite normal for that use. You might try something like that if your area
doesn't get a lot of thunder storms.

--
Dave M

Good judgement comes from experience, and a lot of that comes from bad
judgement.