When we want to adjust voltage and current on circuit to get the desired value , change condition to test the circuit. We have to use potentiometer as it can vary resistance. Refer to ohm's law V = IR . If we change resistance then the value of V and I change too. The potentiometer has 3 terminals and its symbol shown below. How to wire potentiometer , it we will be explained below.
Potentiometer's Symbol
see this photo for example.
This good potentiometer.
This good potentiometer.
This good potentiometer.
When we rotate the knob clockwise and counter-clockwise , the resistance value should be vary from 0 ohm increase to high resistance and from high resistance decrease to 0 ohm. There are 4 type to connect or wire potentiometer which its resistance will vary when adjusting the knob.
1. Wire terminal 1 and 2 , left the terminal 3 open circuit. Shown on circuit number 1 below.
2. Wire terminal 2 and 3 , left the terminal 1 open circuit. Shown on circuit number 2
3. Connect or shorted terminal 1 and 2 together , so it will be as terminal 12 then wire terminal 12 and terminal 3 to circuit.
4. Connect or shorted terminal 2 and 3 together , so it will be as terminal 23 then wire terminal 23 and terminal 1 to circuit.
Connect or shorted terminal 1 and 2 together , be as terminal 12 ,
then wire terminal 12 and terminal 3 to circuit.
Connect or shorted terminal 2 and 3 together , be as terminal 23 ,
then wire terminal 23 and terminal 1 to circuit.
then wire terminal 23 and terminal 1 to circuit.
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