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dpb dpb is offline
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Default Mixing metals in water pipes

Bob F wrote:
"dpb" wrote in message ...
Jeff Wisnia wrote:
...

I'm afraid you are wrong there, dpb. the electrical connection between the
two dissimilar metals does NOT have to be in the (wet) electrolyte area.

I _said_ there's still a potential. But it's still visible for inspection and
it's still the lesser of the evils -- the electrical ground has to be made.


They attach a zinc block to metal parts underwater on boats - sometimes even
with a wire going to an above water connection point. This reduces corrosion of
all the metal connected to it. The corrosion does not just occur at the
connection point. Connect a metal from the other end of the chart the same way -
everything would corrode faster, right?


The also make compatible metal grounding clamps.

However, I've ground connections of copper to galvanized and black iron
that have been in place for 40 years or longer and they simply have not
been a problem.

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