Rich wrote;
Just a note to ask if anyone has any knowledge on auto electrics. I been
chatting to a list member whose electrics are playing up and keep draining his
battery within a couple of miles, even with a new battery and a new alternator.
Any ideas, also the car is fitted with an Alternator to replace the previous
dynamo(generator), so I am wondering wouldn't that make the control box
redundant(could this be draining the power) other than as a means to connect a
few various wires together. Any help by anyone would be appreciated, how about
you Phil W, you work with electrons all day, any ideas :-)
My personnal knowledge of electrics extends to getting an unhealthy dose of 240v
off a Drill in the garage the other the other day(Oouch). So there was nearly
one list member less :-) (R.I.P), who said men don't scream!!!!
A "typical" small battery for an LBC has the capacity for several hundred
Amp-hours. Assuming a nominal figure of 200 Ah, you can draw 1 Amp for 200
hours, 10 Amps for 20 hours, 200 Amps for 1 hour... of course it is not quite
this simple because as the current goes up, the internal heat generated in the
battery by the chemical reaction goes up, as well as the internal resistance and
power dissipated by it. These reduce the amount of power available in electrical
form substantially. To take a fresh battery and drain it in a few miles would
require an extremely high drain, easily over 100 amperes, which would definitely
generate a lot of heat in the ten minutes it might take to go two miles at a
slow speed. Open up the bonnet and see what electrical components are
incredibly hot (glowing at red heat!) after you drive the two miles.
regards, John Pratchios
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