"Tristan" wrote in message
ups.com...

No need to go the "transformer" route. Check yur power cord very
carefully. Pull the pump out of the pond, and clean and wipe the cord
dry. Under good lighting and maybe even with a good magnifying glass
(depending on how good yur vision is) inspect the cord for any nicks
or cuts or cracks. Even a new pump can have a nicked or cut power
cord. This cut or nick can let in moisture which will wick through the
cords fiberous separators and insulation. Eventually it can get into
the area were the wires terminate to attach to plug or windings of
motor and then it changes resistence values which can play hell with a
GFIC device or if its bad enough it can kick off a regular breaker.
Given enough time, it can eventually wick in enough water even through
a very small minute cut to fill any air spaces in a encapsulated
motor, or even fill an oil filled motor up with water and displace the
oil. Also check where cord enters pump housing itself. I would also
give the housing of the pump a good visual inspection for cracks
etc.......Its not at all uncommon for rodents like field mice etc to
gnaw on a power cord, and eventhe portion that is not in the water can
eventually start wicking in moisture. Put a good load on yuor circuit
that you have the pump plugged into. If its a 15 amp circuit load it
up at 15 amps..using other devices (lamps, electric weed eater,
blower, TV etc etc etc) and see if circuit remains ok. If it trips
without the load rating on it,I would replace the GFCI device or check
for loose or corroded connections.

Have fun, remember live circuits and water do not mix so be carefull!
==============================================
I think I will clean off the cord thoroughly and see if there is some kind
of crack or rodent nibbling. We never thought of that. Thanks. I'll let
you guys know if I find anything. There's old mud and thick algae growing
on the cord that could well have hidden such a thing.

All the pumps have been running without a hitch since we removed the bad
one.

I know he checked the circuit but I don't know how. It does appear the pump
was the problem.
--
RM....
Frugal ponding since 1995.
rec.ponder since late 1996.
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
Zone 6. Middle TN USA
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