On Mon, 17 Jan 2000 Z27407@aol.com wrote:
> I need a broken amp meter for an experiment. I have recently put a
> alternator on a TR4a and the customer wants to have an original looking amp
> meter that will read correctly with the high output alternator and I think
> that I can modify a factory amp meter to read up to 60 amps accurately. I
FWIW, ammeters aren't that accurate. They're only an approximation of
what's going on. (or NOT going on)
> just need a broken meter that I can take apart and rework since there is no
> guarantee that this will work. I dont want to destroy a good working meter..
You can alter the reading on an ammeter without getting into the guts of
it. You need a shunt.
A shunt is basically a piece of wire that lets 'most' of the current go
around the ammeter instead of through it.
A while back someone calculated the size & length of steel wire required
to bring the ammeter scale 'down' so that it would read higher (I think 55
A instead of 30A) I can't remember the final results but I think it was
around 5 inches of 10 or 12ga wire, shorting the terminals on the ammeter.
...Of course you still need to pull the bezel off and change the numbers,
if necessary, but IMHO it's an easier fix than fiddling around inside, and
it's 100% reversible.
Anyone got the correct numbers for the Magic Wire?
-Malcolm
* There is a FAQ for this list! Its new home is:
http://www.islandnet.com/~walker05/triumph/trfaq.htm
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