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Wayne.B
 
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Default cross-battery voltage

On Sun, 9 Nov 2003 19:33:18 -0500, "Charles T. Low"
wrote:


However, the thing which really puzzles me is that when (for some reason) I
tested the voltage between the positive and negative posts of the opposite
batteries, i.e. neg on battery one and pos on battery two, and vice versa,
there was a momentary reading in the 5V range, which within a split second
dropped to 1.5V, and from there plummeted. I watched it down to about 0.6V,
but it was still dropping rapidly.

If I let them rest for a minute, the same sequence would repeat. So, I
disconnected the positive leads too, and wiped off any dust and grime from
the battery surfaces, but the same thing kept happening.

Any explanation? I doubt very much that it indicates any kind of a problem.
But I'm not sure. Mainly, however, I'm curious and puzzled. Thanks in
advance.

================================

What you describe sounds like a capacitor bleeding off its charge
through your voltmeter. Other than that it's difficult to say what is
going on. If you have a voltmeter with very high input impeadance,
there's a possibility that you are just picking up stray electrical
noise originating somewhere else. If you disconnect both the positive
and negative leads there should be no possibility of stray leakage. I
usually don't bother however on my own boat, just turn off the
battery switches. The only exception is my generator battery which
has three leads to the positive terminal. Those I disconnect.