Potentiometer Reading Does Not Reach Zero

[sham96]

Hello Everyone!

So in one of our machines , a potentiometer is installed along with an Ammeter display. When the resistance of the potentiometer is changed, the ammeter reading also changes correspondingly. However this reading never reaches zero when the potentiometer dial is at zero! We tried changing the potentiometer with another high-quality one but the same issue keeps occurring.

The ammeter readings of two other potentiometers installed in the same machine work well.

Could anyone enlighten us as to why this is happening? Any help would be so greatly appreciated!

 

[3DDave]

Is there a schematic to show the connection between the potentiometer, the ammeter, the power supply, ground/neutral, and the remaining equipment?

 

[IRstuff]

Do the other ammeters work in the circuit that has the offset? Does the ammeter with the offset show an offset in the other circuits?

Is the ammeter analog?

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[IRstuff]

btw, please refrain from double posting

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[Coco_HueHueHue]

I would place my bet on a bad ammeter.

 

[danw2]

Shouldn't the current go up as the resistance goes down?

Why would the current through a zero resistance be zero? Is the pot at zero ohms shorting the power supply? Is this a crowbar test circuit?

 

[waross]

More important than what the meter indicates is:
What is the actual current when the pot is at zero?
Verify with a known good Ammeter.

Bill
--------------------
"Why not the best?"
Jimmy Carter