Standard Cell

[WXYZCIENCE]

I will start with a picture of this piece of test equipment that my brother Bill found at our local take it or leave it shed in our Sunshine Store (dump).






There was no manual with it. We tested the unit and all seem to be working fine. The heater light is turning on and off about every 5-10 seconds.
The six terminal voltages read 1.018 volts.
My questions:
1. Has anyone on this forum ever used this type of unit?
2. There are two terminals marked, GA, just left of the toggle switch. What are they for and what do I connect them to?
Joseph.

[Flux]

I have no idea what your GA terminals are for.

What you seem to have is six standard cells in a temperature controlled enclosure.

Possibly the terminals are something to do with checking the temperature as you need to know that to know the exact voltage.

These would originally have been used with a potentiometer and compared one with the other to establish the most accurate voltage. You must not take current from them but the 10m input impedance of a digital meter will not hurt them.

Unless you collect curiosities I really can't think what you are going to use them for except to check your digital meter which seems to be spot on.

Hang on a minute, I think your GA terminals and the toggle switch may be part of the comparison process. I think GA means galvanometer. A highly sensitive moving coil galvanometer ( microammeter) that would have been used to detect slight variations between cells. You might even have a basic potentiometer circuit built into the thing.

They will be Weston standard cells, probably you can Google something about them.

Flux

[richard]

 This a 6 cell standand cell box with temp. control.  DO NOT  read the 6 terminal voltage with a METER !!!!!!  Cell voltare is 1.01------   out to 6 places.  Current load  00.0000001 of a amp....GA terminals are for a METER with "0" in center. Curent 0.0002 amp.   richa  c.c. of c.

[richard]

  flux,    thanks   galvanometer is what I was trying to think of.You used a potentiometer with a outside voltage and current to read cell voltage. It been about 32 years sent Iwork with equintment.  Thanks again   richard  C.C. of C.

[terry5732]

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