Changing temperature of a heating element

[Yasashii]

Hi there,

I have a heating element device, like the ones you get in things like hair dryers and heat guns, and I wish to add a pot to the circuit to make it a variable heat setting so that I can run it from 0 to 100%, is there an easy way to add this feature to the design?

Thanks for any help

 

[Reloadron]

A pot alone would not likely handle the current. Hair driers can consume between 1,000 and 1,500 watts under normal running. Even most simple lamp dimmers would not work, unless you find a lamp dimmer capable of 2,000 watts or so. More information on the element would help. But to answer your question in a nutshell, no. You could likely build a triac or scr circuit that would work.

Ron

 

[Yasashii]

The heater runs at 1200 watts from 240 volts. It's a standard wire coil in a circular pattern, looks to me like it runs at 240 volts from the mains.

So any links to websites that might show one of these triac or scr circuits that might help me in the right direction?

 

[Reloadron]

OK, if you follow this link here and scroll down the page you will see a simple drawing for a 1 kW 230V AC light dimmer circuit. Actually the circuit uses this particular triac which according to the data sheet should handle close to what you want. Remember if you choose to build something like this you are working with mains voltage and current so safety is paramount!

Another option is to find a large power lamp dimmer. This is an example of a 1 KW (1,000 Watt) unit for 120 VAC. Based on your location if you could find a high power dimmer that would work fine as you have a purely resistive load with a heating element.

A Google of Dimmer Circuits should bring up countless hits.

I should add that if you build one or modify one other than safety you will need a real good heat sink for your triac! Good heat sink and cooling of the triac will be paramount in importance!

Ron