# Checking Continuity of Potentiometers

Discussion in 'Electronic Basics' started by bassplayer, Sep 13, 2005.

1. ### bassplayerGuest

I'm trying to check the continuity of some potentiometers that I have.
These pots are 250K and when I test them, the only time I get any valid
reading > 0 ohms is when I have the pot turned all the way until it
stops. Should I be getting readings as the resistance increases, such
as 57K, 60K, 100K, 175K, 200K, 243K, 250K (each value being displayed
as I turn the knob)??

2. ### John PopelishGuest

If you measure from an end terminal to the center (wiper) terminal,
you should see a smooth change in resistance as you turn the shaft.
If you measure between the two outside terminals, you should see a
fixed resistance, regardless of shaft position. You have to be using
an ohm meter range high enough to tell that resistance from an open
circuit.

3. ### Peter BennettGuest

The resistance between the end terminals should be 250K, regardless of
the position of the wiper.

The resistance between the wiper and either end should vary
continuously between 0 and 250K as you adjust the pot.

4. ### Mark FergersonGuest

As others have said, yes, between the wiper and one end. Do these
pots have integral switches, and are you measuring across one end of
the pot and the switch?

Mark L. Fergerson

5. ### Jasen BettsGuest

yes, typically.
if these pots have three terminals the outer two should show a fixed
resistance and the middle one shold vary its resistance between the two end
points.

If you have semi-logarythmic pots (marked 250K-A or A250K or "LOG" etc )
most of the resistance change will be at one end of the turning