"Robert Allison" wrote in message
news:joZwi.10203$Ns6.10019@trnddc01...
I built a lake home for some clients and later installed an underground
drop to a pedestal with a 240 volt disconnect (exactly like an AC
disconnect). From there, the people who built the dock tied into the
disconnect to run wire out to the dock.

Then the rains came. The lake rose almost 35 feet in a matter of weeks.
More rain. The lake rose to flood stage and submerged the pedestal. Yet
power remained to the dock. The pedestal was under about 15' of water,
yet did not trip the breaker at the main service. The owner called me and
asked if this was dangerous and I said yes, turn off the breaker at the
breaker box, which he did.

My question is: why did the breaker not trip when the disconnect was
submerged? It is not waterproof by any means.

--
Robert Allison Rimshot, Inc.
Georgetown, TX

There is not enough surface area of the contacts and the water is not
conductive enough to trip the breaker. Depending on how long it was under
water with the power applied, i'd bet there is pretty heavy corrosion of the
contacts.
John