Variable resistors

Submitted by John on

I have a schematic for a basic timer that I would like to build. Within the schematic, there is a symbol for a variable resistor. I believe it is showing only 2 connections to the rest of the circuit.

All of the variable resistors that I find for sale are shown with 3 terminals. What am I missing here?

Hi John, when you are using a potetiometer as variable resistor then you should use the variable pin and any one of the fixed end pin of POT.Leave the rest pin as No connection.Like wise there is only 2 wires will be used.

  Joined August 22, 2019      125
Thursday at 12:29 PM

marry roser

Permalink

A variable resistor is a resistor of which the electric resistance value can be adjusted. A variable resistor is in essence an electro-mechanical transducer and normally works by sliding a contact  over a resistive element. When a variable resistor is used as a potential divider by using 3 terminals it is called a potentiometer. When only two terminals are used, it functions as a variable resistance and is called a rheostat. Electronically controlled variable resistors exist, which can be controlled electronically instead of by mechanical action. These resistors are called digital potentiometers.

 

  Joined November 21, 2019      36
Thursday at 02:40 PM

jaksonlee

Permalink

A variable resistor is a resistor of which the electric resistance value can be adjusted. A variable resistor is in essence an electro-mechanical transducer and normally works by sliding a contact over a resistive element.

  Joined November 07, 2019      124
Thursday at 04:25 PM