I'm working on a project that involves swapping out a couple of pots of a circuit board for a couple of digital potentiomters. I'm trying to make sure that I'm using the right resistance values, so I'm measuring the resistance of the old pots. These are standard 3-terminal pots. I'm calling the terminals
B.For the first one, these are the values I'm getting:
A to B: 4.84k CENTER: A to WIPER: 1.66k B to WIPER: 3.55k ----- 5.21k FORWARD DIRECTION: A to WIPER: 2.333k B to WIPER: 2.785k ----- 5.118k BACKWARDS DIRECTION: A to WIPER: 1.00k B to WIPER: 4.16k ----- 5.16k
I had always understood that the resistance from
WIPER + the resistance from
B should add up to equal the resistance from
B, but no matter how many times I measure the
B resistance is not 5.2k.
Obviously there is something that I'm not understanding correctly. What is it?