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-   -   Making Heating Element From NiChrome Wire (http://www.physicsforums.com/showthread.php?t=585053)

 SteveAlex Mar8-12 02:57 PM

Making Heating Element From NiChrome Wire

I need to make a 1 metre long heating element from NiChrome Wire. The wire I have is 0.9mm with resistance of 1.7ohms per metre. Can I wire it straight to the mains with a light dimmer switch in place to limit the power?

 technician Mar8-12 03:54 PM

Re: Making Heating Element From NiChrome Wire

Don't know what you want the heating element for but you plan sounds ver dangerous !!!!!!
A good heating element is that from a mains soldering iron, depends what you want so this is just a suggestion
If the element needs to be 1 m long think about using a step down transformer to give about 10volts to power the wire like in a hot wire bender

 AlephZero Mar8-12 04:03 PM

Re: Making Heating Element From NiChrome Wire

I agree with technician. If you don't know enough that you have to ask the question, you almost certainly don't know enough to do something like this safely.

The one-word answer to "can I wire it straight to the mains through a light dimmer" is NO.

 vk6kro Mar8-12 08:39 PM

Re: Making Heating Element From NiChrome Wire

I guess you don't mean you intend to use only 1 meter of wire?

Assuming you are winding with this wire onto a ceramic former with a helical track on it, if you had a need for a 500 watt heater at 120 volts, then the wire would have a resistance of (1202 / 500) or 28.8 ohms so you would need 28.8 / 1.7 meters of wire or 17 meters.

The problem with using dimmers is that they turn on fully when they do conduct, so the current into a short length of wire would get get large if only in brief pulses. This is very likely to damage the dimmer.

If you decided you could wind 300 turns onto this former, you could work out the diameter of the former easily.

You can get replacement elements for electric radiators, which are enclosed in a special glass cylinder for safety. Maybe this would be an easier option.

 SteveAlex Mar9-12 06:15 AM

Re: Making Heating Element From NiChrome Wire

Thanks for your replies, I will most likely use a step down transformer if I can get one,
Relax AlephZero I'll be under the watchful eye of my college lecturer when I'm doing any of this lol, its for a college project!!!

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