Dimmer switch not dimming?

[Groenslang]

Hey guys!

Quick question for the guys with the knowledge on electrics, I bought a wall dimmer switch today to connect onto 20W heating cable. I connected the wire like I thought it should be done (the live wire cut with the ends going into the dimmer switch and the neutral still in one piece). Every time I switch it on the wire gets incredibly hot, 50 degrees at least. Am I connecting it wrong or did I just waste R200?

Also, can one cut the heating wire into smaller lengths? I want to make heatmats. It is a serious headache as I need to heat up my AFT and at the moment have to switch it on and off constantly to maintain the right temps.

Any help would be appreciated!

[Urucone]

Just get yourself a thermostat, You already spent R200(That’s half of what a thermostat cost), Like I always say; the more gadgets you have the more things you are left with fixing.

[froot]

Some dimmers will not work if the load they are controlling is below a certain power rating. Connect this dimmer to a 60w light bulb and see if it works.
Depending on the circuit you may need to connect neutral to the dimmer too. Do you have a link to a data sheet of this device, or perhaps a photo? What do the instructions say?

As Urocone said a thermostat is the more elegant solution.

[dannylomb]

Hi,

It is true you could have bought a thermostat that is suited for the job.
The dimmers that is used for lights I am sure won't work for heat cable if you want to do that you will need a habistat and thos are quite expensive.

[Groenslang]

Thanx Froot! Will connect the bulb to it and see if it works! I know a thermostat is the better option (all my other setups run on thermostat), just at home at the moment and in Bergville there is no such thing as a thermostat. Oh ja, and the cable gets up to 78 degrees, enough to melt the plastic casing if left for longer than 5min.

[Smeegle]

Froot is on the money here...

Dimmers have a minimum load rating in the region of 40W, so you would need to connect at least two or three 20W cables in parralel for the dimmer to work. Or connect the 60W globe in parralel with the cable, and use the globe for a night light or halloween pumpkin or something.

It has nothing to do with whether the load is a light bulb or a heating cable as they are both resistive loads.

That said, a thermostat is the best solution.

Also, please don't cut the cable into shorter lengths as by doing so you will be decreasing the resistance and could start a fire.

[froot]

Also, please don't cut the cable into shorter lengths as by doing so you will be decreasing the resistance and could start a fire.

Yes please! Thanks for adding that.