Using a potentiometer to control the speed of an electromotor

[drmechatron]

Hi guys, I need help with a circuit. I have done one couple of years ago but simply forgot how to make it in the meantime so I came here for help.

I would like to connect a Universal 100V - 240V AC to DC power Adapter Charger with Output : DC 24V 1A / 1000mA 24W to a regular toy DC motor like the one here http://i.ebayimg.com/00/s/NjAwWDYwMA==/z/efsAAOxyVtxSMVvs/$(KGrHqVHJEgFIfd7PdhIBSMVvrt,Yw~~60_12.JPG with a potentiometer in between to control the speed of the DC motor. The DC motor works with voltages ranging from 3v (barely spinning) to 24V (really fast) just like the output of the charger.

Please help guys!

 

[(*steve*)]

I recommend you start with a your commercial 24V power supply and then use a cheap DC to DC converter module to efficiently convert this to a voltage between 3 and 24 volts.

These modules often come with a trimpot for adjusting the output voltage. In your application you might remove this and replace it with a suitable potentiometer.

 

[Bluejets]

Go back to ebay and look for a simple DC speed control.
They usually come complete and delivered for around $5-$6.
You would not even think about building one for that price.
As to quality, I have had a similar one driving an auto-feed on my Myford ML10 for years now without a problem.

http://www.ebay.com.au/itm/PWM-DC-M...08?pt=LH_DefaultDomain_15&hash=item3a8dd3169c