Randall has made some excellent points! This subject reminds me of
something my father told me a little while back, and I would like to find
out if the list can confirm or deny the following: He says that a battery
left directly on a metal surface can lose charge through the plastic case of
the battery! You should always have the battery on some sort of insulating
pad. It sounded a little far fetched for me, but what do I know!
Thanks
Rob Swift
Manassas, VA
-----Original Message-----
From: owner-triumphs@autox.team.net [mailto:owner-triumphs@autox.team.net]On
Behalf Of Randall
Sent: Friday, April 21, 2000 12:25 PM
To: triumphs@autox.team.net
Subject: RE: Slow battery drain
John :
As others have pointed out, many stereos and alarm systems draw a few ma all
the time. A clock shouldn't draw that much, unless it has a display that
stays lit all the time. (An old mechanical/electrical clock will draw a
fair amount of current, maybe a few hundred ma or even an amp, but only for
a very brief period every few minutes. Average draw is quite low.)
Another problem I've seen is a combination of dirt (road salt?) and moisture
forming a leakage path to ground, or sometimes the phenolic base frequently
used in relays in the 70's will become partially conductive. I had an Audi
100LS once that would turn on the rear window defogger if the evening dew
was heavy enough.
Which leads me to the next point : 2ma should not be enough to appreciably
drain your battery in a month, unless your battery is extremely borderline
to start with. .002 amp * 24 hrs/day * 30 days/month = 1.4 amp-hours per
month which should be less than 5% of your battery capacity.
The 2ma should be fairly easy (if somewhat tedious) to find : with your
ammeter in place, start disconnecting things until it goes away. I'd
probably start with all the fuses, then the junction on the main battery
cable, and go from there. Unless you have a very good memory, it's worth
taking notes <g>
Randall
John Linnerth wrote :
>
> I find that even with everything off I still have a small
> current flow from
> the battery enough to draw it down in about a month if I
> don't run the car.
> 1976 TR6
>
> I measured a drain of 2ma at the battery.
> Any ideas what to look for, I didn't have this problem before
> I stored the
> car for the winter.
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