Bud :
I posted the info, but it was only for a TR3A ammeter (the only ones I
had).
I have been trying to locate a TR6 ammeter to measure, but haven't found
one yet. One of the local club members promised to measure his, and tell
me the value at the next club meeting, so there's still hope ...
The TR3 info :
>> I just measured the resistance of two Lucas ammeters (both from 59
>> TR3A's, with the setscrew terminals), using fairly
accurate digital
>> meters. Both are 1.2 milliohms.
>>
>> Some quick work with a resistance table & calculator
shows that a 50%
>> shunt (equal resistance) could be made from 5.5" of 14
gauge copper wire
>> (8.29 milliohms/meter) or 3.5" of 16 gauge copper (13.2
>> milliohms/meter). At 30 amps (50% of 60 amps total), the
shunt will
>> dissipate 1.1 watts, which shouldn't be a problem.
>>
>> YMMV
BTW, I have no particular reason to believe the value is different for a
TR6, but Murphy's law says if I don't check, it will be ! <g>
Also, while I have no objection to revisiting the issue, did you know that
listquest.com keeps a record of all our ramblings ? To get the above
quote, I went to http://www.listquest.com/lq/search.html?ln=triumphs and
entered search terms of "ammeter resistance shunt" (without the quotes).
Randall
On Saturday, July 17, 1999 6:56 AM, levilevi@home.com
[SMTP:levilevi@home.com] wrote:
>
> Does anyone have the info. on the length of 14 gauge wire and/or the
> length of 16 gauge wire to use as a shunt on the ammeter? We had a
> thread a while back on this subject but of course now that I'm ready to
> do it I can't find the darn info.
>
> I was thinking 4 inches of 16 gauge was suggested.
>
> Anybody save the info. or is Randall or Dan online yet?
>
> Thanks in advance.
>
> Bud Rolofson
> 71TR6 CC57365
> 71TR6 CC65446
> 66TR4A CTC57806
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