On 2006-03-08 18:58:29 -0800, said:

John;

I think there is no reason for it to even tolerate 20 volts. It does
not need any voltage higher than its test signal. Setup to test current
or voltage, doesn't matter.

If you want to test ESR on charged batteries, you can capacitively
isolate it with a large electrolytic.

BTW, what kind of ESR readings should one expect from a given battery ?
Is it like a go/nogo thing, or are you trying to match these batteries
in series or something like that ?

You have piqued my curiousity.
JURB

Ah, well, I did provide the link to the battery test on flippers. Not
much info, but it is a guidline for interested folks to expand on.

I wanted to protect the meter from accidental surges. I also want it to
be somewhat idiot proof. So having to remember to put a capacitor in
series with the meter to check a battery is easy to forget...don't ask
how many times I've destroyed a peice of test equipment by touching a
charged capacitor or live circuit (OK, maybe ten times). Bob and I have
had too many (perhaps 20(?) out of 12,000) kits blown up blown up and
more simply damaged.

I got the MOVs (Panasonic ERZ-V07D220) from Digi-Key for $0.34C - about
30 cents US, 20V 250A.

Best to quote messages you respond to as well, so here is the link I spoke of:
http://www.flippers.com/esrkthnt.html#battery

John :-#)#
--
(Please post followups or tech enquires to the newsgroup) John's
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