How to slow down a electric motor

Thread Starter

spike1947

Joined Feb 4, 2016
84
Hi
I have a electric motor from a houshold vacuum cleaner that I want to power a small blacksmiths forge , but it is to powerfull , what I was wanting to do was try to slow the motor down with a resistor ! .
Would that be possible .

cheers

spike
 

MaxHeadRoom

Joined Jul 18, 2013
19,156
You need to get the power tool version, either that or DIY version if the former is not available where you are.
Throttling the output, lowers the motor current but heating may occur due to reduced air flow.
Max.
 

Thread Starter

spike1947

Joined Feb 4, 2016
84
You need to get the power tool version, either that or DIY version if the former is not available where you are.
Throttling the output, lowers the motor current but heating may occur due to reduced air flow.
Max.
That sounds expensive ! .

cheers

spike
 

wayneh

Joined Sep 9, 2010
16,114
I thought about that , but would it not overheat the motor ! .

cheers

spike
Unlikely, but you could build in a slipstream to keep a small airflow over the motor even if the main flow is cutoff. The motor will act like a vacuum cleaner motor when you block airflow. It’ll speed up a little because there’s a reduced load.
 

wayneh

Joined Sep 9, 2010
16,114
I agree that’s an excellent solution unless you need fine control at the very low end, for instance the ability to choose 2% versus 4% flow.
 

Thread Starter

spike1947

Joined Feb 4, 2016
84
There are several for ~ $2.00 each on ebay and Ali express etc,
AC 220V 2000W SCR Voltage Regulator Dimming Dimmers Speed Controller


Max.
Thanks just what I am wanting , trouble is if they are from China I may not get it untill quite a few weeks time , I could really do with making one , have lots of electronic parts , would anyone have a schematic of this type of controler ! .

cheers spike
 
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