Linking an arudino to a kettle element

Hello new community! Before I buy my first arudino I need to just check I get the right one for my first project idea...

A Teasmade!

Just wondering if an element like this could be added into the circuit

I've done some electrical work in the past and have reasonable coding knowledge which I would really like to apply to this exciting 'newish' area of computing.

My current primary requirement is to understand and acquire the components that are necessary (which arduino + extra's) and how to step the power up to 240V (or as high as necessary)

Please help!

Beside the Arduino, you will definitely need a relay (and a diode).

you will definitely need a relay

And a hefty one at that! 13A at 240V?

What is the Arduino going to be doing, other that acting as a switch?

My current primary requirement is to understand and acquire the components that are necessary (which arduino + extra's) and how to step the power up to 240V (or as high as necessary)

There is no way you are going to get the Arduino to produce 240V AC. And 13A? Forget it.

To switch 240V @ 13A from an Arduino, use an SSR.

SSR? Typo?

Solid State Relay.

Ah yes. That got my brain kicked back into gear. For some reason "SCR" got stuck in my head.

A 10A 240V relay on a board with an opto-coupler, indicator LED etc you can get from e-bay for a couple of pounds. I've only switched small loads with them but they are rated for 10 amps.

The full 13A by contrast is rather harder to find. I'm sure that 13A 5V relays can be found, and indeed that solid state relays could be used but there's a lot more messing about involved. As a first project, if you can limit yourself to a 10A/2.4 KW element then there is an easy off-the-shelf solution. You then only need to provide the relay with +5V/Gnd power and a data line from your Ardu'.

Something like this:

(I haven't used that seller but that's just an example of what I mean)

This looks almost too good to be true.

I agree, that does look too good to be true.

Things you have to think about before buying:

  1. It comes from Hong Kong - it’ll take forever to get here.
  2. It comes from Hong Kong - there’s a couple of quid extra postage to add to the 99p.
  3. It comes from Hong Kong - do you really trust it?

(3) is the big iffy one for me. I wouldn’t buy high voltage. high current hardware like this from somewhere I didn’t trust. If something like this goes wrong then it goes wrong in a big way. I would be far more inclined to buy one from a reputable retailer - that way you have some kind of guarantee and comeback if it does go wrong. Something like:

Also there is a datasheet for the one from Rapid, showing you amongst other things the heatsinking requirement.

I bought a Fotek solid state relay from China (I think) from eBay. They seem to be a good brand and do 25 and 40 amp versions. I've seen a few other people use them, some for boiler control...

Ok so I want to form a 'shopping list' then I can cost this up and make the project. :D

If I should be posting elsewhere please help out! :)

So far I have these items in mind

[u]Main Electrical components[/u] 1. Arduino (not sure which one) 2. Kettle Element ( 3. Relay Element (something like this (unless it's going to blow my arm off:

[u]Sensors[/u] 1. Heat sensor 2. Water level sensor (like a ball-cock (toilet cistern float))

Plumbing 1. Copper piping (or alternative) 2. Water chamber that can handle some pressure

Why do you want a water chamber that can handle pressure? Much safer to vent the chamber (as in a kettle) so that if the heater stays on too long, the water will just boil off rather than the whole device exploding.

I'm initially considering having the presure of the water boiling forcing the water down a tube into the cup/teapot. If you have a safer idea, I'm all ears.

I just need alot of help at this stage and it would be great if you more experienced guys could help :)

I really need to know exactly what I need.

Is it an ardu' uno, is that fine or should I opt for another. Do I need a shield?

I also could do with help on the plumbing side, just to work out the best way to get the boiling water to the cup...


OK, I see what you're getting at. You'll also need a sensor to detect when all the water gone so you know to turn off the heating element before you burn it out or melt the whole thing.

if it helps, a “real” teasmade has a switch under the kettle
the weight of a full kettle holds the switch closed
as the water gets forced out, the weight decreases until the switch activates

the kettle has a screw top lid, and a pipe that comes out (like a spout) into the spout of the teapot part
pipe leads down into the kettle to almost the bottom so as the steam build up the water is forced out

kk, thanks for the extra tip. I'll start assembling soon.

Just need to know which ardu' I need, is uno fine?

Uno is more than enough.