manual simple temp controller

[phonetic]

temp controller a.jpg

here is my DIY temp controller using common bits, total cost $25 to use with 2.5kW heating element.
disclaimer, only do electric projects if know what doing, or know someone who does.

[Meatheadinc]

Looks neat.
SCR controller ?

[phonetic]

yeah triac actually, phase control 4kW, seems to dissipate 10 watts approx 1 volt drop across input-output

[Meatheadinc]

Nice It should serve you well :handgestures-thumbupleft:

[LBextreme]

here is my DIY temp controller using common bits

It looks to me like you have the earth (yellow/green to socket) and the neutral (blue to socket) connected together with the brown (neutral from plug). Is this correct?

Also, what gauge is your mauve wire to and from your ammeter.

[Meatheadinc]

Active wired in series through triac and Amp meter ??(brown and mouve)
Neutral and Earth straight to socket (blue and green) ???

:obscene-drinkingdrunk:

too drunk to think will look tomorrow :obscene-drinkingchug:

[LBextreme]

Active wired in series through triac and Amp meter ??(brown and mouve)
Neutral and Earth straight to socket (blue and green) ???

:obscene-drinkingdrunk:

too drunk to think will look tomorrow :obscene-drinkingchug:

Are the three wires I have circled terminating together?

[Meatheadinc]

don't think so.
looks like the inlet wiring. It is in the same white insulation as the in feed .
I think we are looking at the top plate of the enclosure upside down on the box

[CH3CH2OH]

confusing angle but looks right to me too

green - ground
blue - neutral
brown - hot

[Matt_Pl]

It would appear to me that The circled wires is actually the TPS cable coming into the unit.

Neutral and earth go straight to the power point the active feeds to the triac then amp meter in series then to the power point.

[benpandaae86]

The only prob i see would be wire size it may heat by the end of the run i used to use a cheap extension lead and used to get warm till i had the sparkys make me a bigger one

[Meatheadinc]

I am sober now and stick with last nights comments

[phonetic]

Extn lead rated at 10 amps, Arlec brand from bunnings, purple wire 1mm multi strand, works a treat lead 1.2 mts long, lead does not feel hot when boiled 25 lts water, meter shows a shade under 10 amps wound up

[CH3CH2OH]

If you are running that close to your wire rating you should upgrade. Code here says you can't exceed 80% of a wires rating means I'd recommend using thicker gauge wire. For the cost of 1.5 meters of wire use thicker gauge wire to be safe as the can heat up over the course of a several hour run.

Personally I'd never use anything rated below the rating of your circuit breaker. The breaker should be the weak link to protect everything else in your circuit and I never use anything smaller than 15 amp wire. Wire is cheap, electrical fire is not!!

[CH3CH2OH]

I am not a sparky but here is my OPINION.

Re-reading the post your controller is rated at 4kw means it is capable of drawing over 18 amps depending on the size of element you use in your boiler. If down the road you replace your element to a higher wattage element you could have a serious problem with the gauge of wire you are using. It may work now but forgetting element size when yours burns out or you want a faster heat up time down the road could = electrical fire

This is a good example of the dangers of using wire rated less than the capabilities of the device. 4kw controller means your wire is rated way to low for the capabilities of you controller. All wire in your controller supplying power needs to be changed.

18.18 watts possible draw means for code here you will need wire rated at 25 amps which is 10 gauge.

Always have a qualified sparky check your stuff.

Just my opinion

[wildburkey]

Nice build, and interesting safety discussion. Seems you have done your math for what you are using it for and some fair points of concern have been raised. Great to see everyone looking out for you here m8, maybe if you clearly label the max load it might meet AU standards, lol.

[phonetic]

Remember only using 2400W element, 10 amp GPO & Plug, indeed if want to use 3600W element, will need 15 amp GPO, cable & Plug, will never use anything larger.

[Triangle]

Just thought I'd chime in, FWIW appliance wiring standard is different from fixed wiring. The cable sizing can be chosen based on the maximum current the appliance will draw and is irrespective of supply wiring.

Your other option for cable selection is silicon flex if you need to keep cable CSA small and current carrying capability high for whatever reason.