[GreenKeys] Milliamp meter shunting...

[Roy Morgan]

Ken,

Yes, your meter apparently needs a shunt to operate correctly.

Do you have any sort of DMM that shows current?  (The Harbor Freight one
does I think - cost is usually four dollars.)

You can easily make the shunt(s) you need, often with a piece of #22
telephone wire, or some low value resistors.  You can get an approximate
cut and try value for the shunt with a known voltage and a known resistor
(say 10 volts, and an R for some value of current in the upper third of
your meter).

There are period catalogs for Simpson meters that would tell you the full
scale current for your meters, and maybe the internal resistance.  (there's
a procedure you can use to measure the internal resistance of a meter
fairly easily.)
Roy

On Sat, May 6, 2017 at 1:49 PM, Kenneth Gartland <trnsrme at gmail.com> wrote:

> Hi guys...
>
> I have a couple of old Simpson ma meters rated
> at 100 ma... both pegged at over the scale limit...
>


-- 
Regards,
Roy

Roy Morgan
k1lky since 1958
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