variable resistor is different from potentiometer

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Jane123
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variable resistor is different from potentiometer

Post by Jane123 » Wed Nov 16, 2016 7:12 pm

What is the difference between a variable resistor and a potentiometer?
Below are 3 answers:
1. Variable resistor is used to carry the current while providing voltage drop.i.e. on a dimmer switch, the more resistance it puts out, the darker the lights are.
Potentiometer is basically a Variable resistor, but it works as an input sensor which provides a signal. it does not carry the current goes to the load component.i.e. the foot pedal on a Tig welder, it tells the welding power source how much amperage it needs to put out, but, welding current doesn't flow through the foot pedal itself.

2. A potentiometers is a type of variable resistor. The two main types are potentiometers and rheostats. Here is the slide I use to explain the difference in the basic transit bus electrical class that I teach.
Generally potentiometers are used as sensors where the signal wire just senses voltage and does not support a load. Rheostats are used to vary the voltage/current to a device that you are trying to control.

3. For the most part, a potentiometer is a resistive element that has a sliding bar across it. Classic example.....volumn control on a radio. A voltage will be applied to one end...the other end to ground....lets assume we have 10V applied to it. As you slide the arm across it, the voltage that it will pick up is a ratio of the length of the resistive element....if your in the middle....5V.
Whereas...a variable resistor is typically a resistive element where you can vary the resistance. In some of the older high powered electronics the variable resistor would look like a wire wound ceramic rod....the arm would be a metal clamp that you could slid down the resistor. This would allow you to adjust the total resistance a circuit might see. A classic example in this case would be the dash light dimmer on your car.

Do you know any other differences between them?

Garth
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Re: variable resistor is different from potentiometer

Post by Garth » Wed Nov 16, 2016 7:33 pm

A potentiometer, informally a "pot," is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat. (Thankyou Wikipedia for agreeing with me. :D ) Whether or not there is significant current running through the wiper is irrelevant.
http://WilsonMinesCo.com/ lots of 6502 resources

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