"Leo Lichtman" writes:

"Curt Welch" wrote: (clip) It seems to me that keeping the battery
connected is more likely to protect
all the electronics in the car than harm them while welding. It acts as a
voltage regulator so in case there are any currents induced in any of the
wires, it's more likely to clamp the voltage levels to 12V instead of
allowing them to rise to higher levels that could do some harm.
Actually, following that logic, you should turn everything on--radio,
ignition, lights, global navigator, etc. Otherwise, the 12v clamp isn't
there.


Just about anything somebody would regard as "modern" electronics that
might be damaged by the welder is actually still powered-up (albeit in
a standby mode) even when the ignition is turned off -- that certainly
includes the engine controller and radio. Haven't checked, but I'd be
pretty surprised if that wasn't also true of the transmission
controller, GPS, etc etc.

The only thing I would expect to be protected by disconnecting the battery
is the battery.

And it will carry more current without harm than most welders will put out.

Right.