What kind potentiometer?

Thread Starter


Joined Oct 20, 2011
I am looking for some help to identify a part. I know is a circular dial potentiometer but what does the letters on the back mean.

Photo attached.



Joined May 11, 2009
To me it looks like some sort of standard pot. The markings on it is probably hidden under label. And I think the label is something placed by the manufacturer(of the unit not the pot it self). Can you measure the resistance between the two outermost pins?


Joined Nov 3, 2012
I agree it's possibly a 5K value.
Frequently in audio equipment a log taper is used for volume control, but the "B" normally indicates a linear taper type.

(A linear will measure 1/2 the total resistance from one end to the center pin when the wiper is centered)
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Thread Starter


Joined Oct 20, 2011
I can't really measure it, as it is broken. The idea is to find a replacement for it, so that I can restore my humidifier. My daughter move the dial so much after the limit that it broke and it is now set to one setting permanently.

I was looking in digikey for a replacement, but without knowing what kind it is is hard to find what to order. I know know is linear Thanks to you guys, how to find now which one matches and I should order.


Joined Feb 11, 2008
Nope, I'm voting for "B5K" which is a standard marking for "B" linear pot of 5k ohms.

Plenty of commercial devices use linear volume pots, and they're actually my preference on amps.

Since it is used in a humidifier control circuit linear is more likely.

To Gunfus; even if the pot is broken, you can put a multimeter (ohmeter) probe between each end of the black resistive track and the centre of the track.

That test works fine even if the pot is smashed apart. If it is a linear pot the two tests will both read about 2.5k ohms.


Joined Apr 16, 2010
I agree with Roman; it's a 5k linear pot. The word "volume" refers to the amount of moisture in the air it produces (or perhaps the amount of moist air) as opposed to sound volume. As such, there is no need for a logarithmic function.