I want to make a 1.5v motor spin by using a variable speed controller (like a pot) how do i do this????

Question

i have a 1.5v motor and id like to control the speed of it by using a potentiometer (like a variable speed potentiometer) how do i do this? is there alot of other components needed to do this? what do i need to do this simple project? is there any circuit diagrams online that i can use? any help is much appreciated!

Answer 1

Call Radio Shack and ask if they have a 25-Ohm 3-Watt Rheostat catalog number 271-265 in stock. If you buy that and connect it between one terminal of the battery and one terminal of the motor, it will have a good chance of doing what you want. Use the center terminal of the three terminals on the rheostat and the terminal that is in counterclockwise direction from the center terrminal looking at the front. Turning the shaft fully clockwise should give full speed and counterclockwise from there should slow it down. While you are at Radio Shack, you can buy a k**b that will fit the rheostat, a switch to turn the motor on and off and a battery holder.

25-Ohm 3-Watt Rheostat catalog number 271-265

http://www.radioshack.com/product/index....

Answer 2

Depends on the size of the motor, and it's current drain. I'd measure the current, calculate R = E/I and get a pot 2-3 times larger than that in series between the motor and the battery.

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Answer 3

There are loads of different ways to do this sadly (for you) the simplest way is unlikely to work - if the motor current is very low (which I doubt only being a 1.5 volt motor) you could just put the pot in line with the power supply (makes no difference if it's in the +ve or -ve line) but the pot would need to be rated to at least the maximum current requirement of the fan or it's get hot and melt - in my experience this way won't work but you might be lucky.

A better way would be to use the pot on the input of a transistor to vary the output voltage there will be loads of suitable circuits on the net (do a search for transistor controlled voltage in the title).