## Re: old ammeter

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• You are right Dave. For DC: V_fullscale = I_fullscale * R_coil So if: I_fullscale = 45.8 uA R_meter = 982.5 Ohm V_fullscale = 45 mV
Message 1 of 51 , Feb 14, 2013
You are right Dave.

For DC:
V_fullscale = I_fullscale * R_coil

So if:
I_fullscale = 45.8 uA
R_meter = 982.5 Ohm

V_fullscale = 45 mV

--- In Electronics_101@yahoogroups.com, Dave C wrote:
>
> What if the meter is labeled "F.S.=45.8 uA"? The meter coil measures just under 1K ohms.
>
> Is this just another way of labeling the meter as (nominal) 50 mV?
>
> Thanks,
> Dave
>
> -=-=-=-
>
> On 13 February 2013, at 5:12 AM, Kerim F wrote:
>
> > ...
> > In parallel.
> > An ammeter is actually a sensitive voltmeter.
> > It seems the full scale voltage of your ammeter is 50mV.
> > If the the shunt is 1 Ohm, the full sacle current would be 50mA
> > If the the shunt is 0.1 Ohm, the full sacle current would be 500mA.
> > If the the shunt is 0.01 Ohm, the full sacle current would be 5A.
> > If the the shunt is ?? Ohm, the full sacle current would be 100A ;)
>
Message 51 of 51 , Mar 21, 2013