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Rod McInnis
 
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Default Removing battery


"jps" wrote in message
...
In article , gould0738
@aol.com says...

Remove the negative cable first, then the positive.


Chuck, can you explain why? I'd think it'd be safer to remove the
positive first...



On a boat it isn't as critical as on a car, but it still applies.

In a car, all the metal surrounding the battery will be at the "negative"
potential. If you put a wrench on the positive terminal, then rotate the
wrench as at it will go it will very often hit something metal. You have
now created a short from the positive terminal, through the wrench to the
frame of the car. Very, very bad things occur when this happens.

If you start by removing the negative terminal, then touching the wrench to
the frame is harmless because they are already at the same potential. Once
you have the negative terminal off the frame is no longer at any potential
with respect to the battery so the positive terminal is now safe.

Rod