[earlsta]

Hey everyone, I'm trying to fix my lizard enclosure with a thermostat, I'm having a little trouble wiring it.
My aim is to connect my lightbulb to my thermostat... having the lightbulb turn off when the thermostat temperature is high.

I've powered my lightbulb no problem, it's just figuring out the thermostat.
The thermostat has 3 terminals,
1x black
1x red
1x no colour
It also has an screw on metal for the earth(green)

My lightbulb socket has 2 wires
1x blue (-)
1x brown (live)

My power cord has 3 wires
1x blue (-)
1x brown (live)
1x green (earth)

So I basically want to make my light globe switch 'OFF' when thermostat temperature is too high! I need to power my thermostat first, can I power it with the same extension cord as the one that's plugged into my globe?
Here are some photos to explain things a little clearer.

Thermostat


Thermostat Terminals


Globe Wire


Extension cord Wire


I hope someone can help me here :) I guess it doesn't seem hard, I just cannot figure it out!
Black terminal is obviously live, and red is negative. I've been told to wire it in a series, any ideas!

[earlsta]

Also here is a photo of the wiring diagram on the back of my thermostat, sorry they are a little unclear, I'm only using a phone camera.

Here's the wiring guide, it goes by number of terminals.
From left to right if its unclear to see,,
1, 3, 2, 4, 5, 6

Click to make larger.

[labman]

Many thermostats have a red wire connected to an R terminal and switch power to a white wire connected to a W terminal. If yours has those markings, run power from the extension cord to the R terminal, and then to the light bulb from the W terminal with a white wire running back to to the white wire of the extension cord from the light bulb. If the terminals aren't marked that way, use any 2 of the terminals. If it works backwards, the light out when too cool, switch one of the wires to the unused terminal. If the light never comes on, switch the other wire to the first terminal. With 3 terminals, power connected to one terminal will be connected to one terminal below the set point, and the other above it.

Many thermostats are only made to switch 24 volts. Unless yours is labeled for 120 volts, it might be safer for your lizard to use a 24 volt transformer. To get the heat you need, use a bigger light bulb. A 100 watt bulb will use 20 watts at 24 volts.

[earlsta]

Thanks for you're reply, but I'm slightly confused..
I was trying to wire this all up, using the same extension cord (3 wires), to power my globe & thermostat. Was I doing this wrong? Do I need separate cords to wire these two individually? My terminal has a Red marking and Black marking on the thermostat, but the instructions tell me not to connect anything to the red terminal. Just to black, and the 3rd one. The terminals are marked by numbers not letters, 1 3 2 4 5 6, in order.

[labman]

If you want the thermostat to switch the globe on and off, you must feed the power through the thermostat to it, or to a relay controlling the globe. If the directions say not to use the red terminal, use the other 2.

Connect the 2 brown wires to the thermostat, one to black, and one to no color. Connect the blue wires together. Connect all the green wires together and to the screw on the thermostat. It should work if the voltage isn't higher than the thermostat is made for.

[earlsta]

Ok thanks for you're reply, I've done what you've told me.

Thermostat Terminals
1. I've wired brown wire from extension cord to my black terminal on thermostat.
2. On other terminal (non red) I've wired my brown wire from my light socket.
3. I've earthed the green wire to my metal chassi on my thermostat from extension cord (heat globe didn't have a green wire, so only 1 earth used).

Ok then I wired the two blue(negative) wires together one from extension cord, one from light socket.
Now when I turned the power on KABOOM it all exploded!
Just kidding, when I turned it on my globe lit up and worked, it would have received power from the thermostat.

The only problem now is.. the globe does NOT! Turn off :(
I need to be able to get it to turn off.. once the temp has been too high.

[labman]

To help more, I may have to have a better picture of the thermostat wiring diagram. When I clicked to enlarge, I only got the same picture again. If the thermostat was not rated for the voltage you used, it is possible you have welded the contacts and it will never work.

[earlsta]

Okay well here it is,
the globe is powered through the thermostat, and actually lights up.
So it's actually working, it's just the thermostat is not turning the globe off.. I'm not sure if I've stuffed the switch up somehow.. I just noticed before I accidentally stuffed my wire up on my globe, I swapped negative with Live wire lol! Oops.
That caused the safety switch to go on a couple of times, could I have damaged the thermostat switch by doing this? Or would nothing work if that was the case? Because my light is getting powered through the thermostat.
Here is the picture of my diagram

The terminals 1 and 3 are the only ones that matter, PNE = is obviously positive negative and earth, hopefully you can see the other lines clearly.

[labman]

Does the thermostat give a voltage rating on it? In the US, most of them are designed to work on 24 volts. I do not how they work in the UK as I am guess you are. If you applied 220 volts to a thermostat meant for a lower voltage, the contacts might weld shut, and it would never shut off. Also, older thermostat here used mercury in them, and needed to be mounted correctly in the vertical position.

[earlsta]

Hiya, well in australia you get a bigger shot 240VOLT! Lol
Yeah my thermostat is rated for 240volt, and my light is 240volt everything here is 240volt. Hmm
Thanks heaps for that verticle position information!! I haven't mounted it while I was testing it, so maybe that could be why!
It's a pretty new thermostat but I'll get if a shot!
Thanks

[earlsta]

Hey well here is my thermostat connected.



The white cord is my extension.
Dark Gray is my light socket.
When turning the power on, the bulb will light up, it just won't turn off!
This is the IMIT TA3 statistics more can be found

http://www.imit.it/dati/schedaArtico...rticolo=F01350


Temperature range 5°÷30°C
Temperature differential <1K
Protection degree IP20
Insulation class I
Output switching contacts
Contacts rating 16(2,5)A/250V~
Maximum standing temperature 50°C


I hope my thermostat is still good and working.. I don't think I've welded them shut

[labman]

I see no reason why it shouldn't work.

[earlsta]

Hmm damnit, okay well here's a diagram I drew up myself, by looking at the wiring diagram on the thermostat case.
I hope this can make things a little more clearer.

I have my brown wire from extension cord (live) going into terminal 1.
Then my brown wire (live) from light socket going into terminal 2.
Earth from extension cord screwing onto thermostat screw.
Two blue wires (-) from thermostat and light socket connected, light turns on, but does NOT turn off when I adjust temp!@

[fish187]

Hay man I've got three wires coming from my light br/b/gy and does your thermostat click when you go to off pos if not relocate nob pos