I'm trying to wire a power supply to a digital temperature controller. I know squat about electrics, but am following this guide - I bought the same components he used to keep it simple, but it seems that the wiring on the temperature controller is different to his so was hoping I could double check that I was going to wire it correctly before proceeding!

This is how I currently plan on wiring it:

Wiring diagram


You would want to wire it just like the picture shows...

enter image description here


The Black wire is N or Neutral

The Red wire is L or Live


  1. You use a short jumper to to connect the red wire from the power input terminal to the load terminal. This is the same electrically, just maybe easier to connect...

enter image description here

  1. You could switch the red and black wires and everything would work, but typically you want to disconnect the live (red) line when turning off the load so that there is no high voltage getting to the load when the switch is off. This is for safety. If you turned off the black wire, there would still be high voltage AC going to the load on the red wire, but the load would not turn on because there was no circuit.

  2. There is no connection to the green (earth) wire on your controller, but you should connect the green wire from the plug to the green wire on the load, again for safety. That would look like this...

enter image description here

  • 2
    \$\begingroup\$ Doesn't this work out exactly the same as the OP's diagram, give or take the wiring colours? \$\endgroup\$ – Simon B Dec 2 '15 at 15:12
  • \$\begingroup\$ Maybe, but brown and blue are non-standard colors so it is not clear what they are and where they are connected to. Assuming that blue is N and brown is L and that they are connected to the appropriate pins in the socket as such, then yes - his connects are correct. But with 240VAC, better to be overly specific! :) \$\endgroup\$ – bigjosh Dec 2 '15 at 15:29
  • \$\begingroup\$ That may well depend on where you are. Here in Europe, brown = live, blue = neutral and green/yellow striped = earth/ground has been standard for several years now. Appliance flexes have been using those colours since the 1970's. For fixed wiring, it became the standard in 2004. \$\endgroup\$ – Simon B Dec 2 '15 at 17:09
  • \$\begingroup\$ In that case, the OP's diagram is exactly correct! \$\endgroup\$ – bigjosh Dec 2 '15 at 17:12
  • \$\begingroup\$ Yeah sorry I'm in the uk and didn't even consider that there were alternate wire colours elsewhere. Thanks for note 2 as well, i'd kinda guessed that the switch would want to go on the live wire but didn't know exactly why! \$\endgroup\$ – Jordan Wallwork Dec 3 '15 at 19:04

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