[volt-nuts] volt-nuts Digest, Vol 36, Issue 14

[Dan Kemppainen]

This one looks more complex than you describe.

However, I have one of the more simplified units, as you describe (At 
least, I think I do), which I would like to learn more about...

Dan



On 8/24/2012 8:00 AM, volt-nuts-request at febo.com wrote:
> Its a potentiometer used to measure dc voltage.
> A standard cell was used to set the total voltage across a series string
> of resistors and a slide wire.
> The dc voltage to be measured was balanced against the voltage developed
> across a selected substring of resistors and the tap on a slide wire.
> Lead acid batteries and similar cells were used as a source for the
> slide wire and series resistor string current.
> A galvanometer was used a s a null detector to determine when the
> v0oltage across the slide wire and series resistor string were equal.
> The resistors were typically immersed in mineral oil contained within a
> copper tank below the ebonite (or similar ) faceplate.
>
> Bruce