13A/3kw temperature controller?

[troublebrewing]

Am I right in thinking that the 12v ETC200 can be used in a vehicle - but obviously only until the battery(s) fail?

[troublebrewing]

Got my ATC-800+ this am (fast ebayer)... I saw in a post that you guys are joining up the earth in a rank of terminals... but why isn't there and earth point on the ATC itself? Or what am I missing?

[beermonsta]

You can use the 12V unit in a vehicle - but there aren't many brewers who transport their FV's around with them!
If you didn't have mains voltage for instance then you could use a 12v car battery (or even better a 12v caravan "leisure" battery) which would be an option.

There isn't a need for an earth point on the ATC as it's probably doubly insulated. Do make sure though that all other electrical devices are earth "bonded" together to maintain safety.
For instance here is how I wired my ATC 800 (not plus) up..

and the incoming earth is connected to the sockets that provide switched power to the cooler and heater, thus ensuring those devices are earthed safely.

[troublebrewing]

Cheers, BM.

[troublebrewing]

When you apply power to the unit, and you don't actually attach a fridge or a heater to the 'stat, does it register power on the terminals?

I got my 800+ today, and in the various modes (cooling/heating), I can't see anything on my light-up screwdriver on any of the terminals except the power-in one.

[troublebrewing]

ok, here's some pics of the ATC.

The lights show that it is in heat mode, but when I touch the terminals at the back with a sonic screwdriver, I don't get any reading that says those terminals are live (only the input live (brown) is).

What might I be doing wrong, anyone?



http://www.flickr.com/photos/24015487@N ... 908640003/

IMGP3384 by Tim Redberry, on Flickr

IMGP3385 by Tim Redberry, on Flickr

[Kev888]

Hi,
You have supplied power to the ATC and also connected the sensor, so it is functioning - you should be able to hear the relays clicking.

However in these pictures you have yet to supply live for the relay contacts to switch to anywhere. If you look back at my post earlier or trace the wires in beermonsta's picture above you'll see that the ATC needs live to three of its pins - pin7 you have already connected, but you still need to connect the live to pins 2 and 4 . Then when the cooling relay operates the ATC will switch the live through from pin2 out to pin 1, and when the heating relay operates it will instead switch it through from pin 4 out to pin 3.

We all have our different skills and it seems likely that quite a lot of this is fairly new territory for you; I know you have taken responsibility for doing this but if you are determined to press on take enormous care and please watch out for yourself. Someone recently did something by mistake that would have made their whole fridge casing live

Cheers
Kev

[troublebrewing]

Ok, I can see where I went wrong on two counts:

1) not examining BM's photo closely enough
2) thinking that the live connections were all linked up inside the ATC

Many thanks Kev, I'll finish this wiring later.

[beermonsta]

Again, like Kev said, be careful ...
My ATC is an 800 not an 800+ which has a different wiring layout - use mine by all means to grasp understanding but don't copy that wiring set up fully if you have an ATC800+.

(Ironically I have an 800+ to swap it over to as the 800 temperature range is too narrow for me) - When I do it I'll re-take a photo for comparisson.

[troublebrewing]

A big thanks to Kev for his pms explaining stuff I didn't understand, and to BM for that clear picture in the earlier post that I should have taken more notice of. Yes, I have seen that the cooling and heating terminals are in different places.

Now, I don't brew my own beer - I stopped a couple of years ago, and only had rudimentary kit and I never really got into the technical aspects.

For example, I didn't have fridges and heaters going.

So, can someone give me a potted reason as to why you brewers need, or can benefit from, heating and cooling your brews? On the face of it, the ATC, and similar devices, seem to offer you the chance to cool something down, and then heat it back up again, and so on and so forth. But why are you doing this?

Reason I ask is because I would like to know if there are other applications for having this unit. What else would you possibly want to heat up ad cool down? Sounds to me like a culinary application - indeed, the brewing world is cooking of a sort, isn't it?

I look forward to hearing what you think. In the meantime, I'm going to sort out an enclosure of some kind and get some terminals and crimps sort to do a proper job on this. I'm planning on having trailing leads as per the Forrtex ATC, which will also allow the box to be smaller, not having the power sockets in it.

TB

[Kev888]

Glad you did it! Good luck with the final touches.

The usual reason for us controlling temperature is to keep the wort at the right temperature for fermenting irrespective of what the ambient temperature is doing. Too cold and it stops, too hot and you get excessive/unpleasant yeasty character. We can cool it afterwards to help it clear though, and also true lager yeast needs cooler temperatures than ale yeast to ferment nicely and more complex temperature management to lager it.

A second reason is that its good to keep beer cool for conditioning and also for serving, again rather than it just following whatever the environment is doing.

In my case I also use a temperature controller to automatically get the liquor at the right temperature for mashing and sparging the grains whilst brewing, which is where the 3kw immersion element came in and why this thread originated.

Cheers
kev

[jmc]

I had a go at doing a drawing:


The left hand side is from the Fortex instructions, with the ATC switching the live to the socket directly. In the right hand side the ATC switches the live to the relay coil instead, and the relay switch/contacts (which are of course rated for higher current than the ATC) then switch the live to the socket.

EDIT: Please take note that this is going outside the instructions that come with most temperature controllers, so don't attempt it if you're at all uncertain of how to do so safely.

Cheers
Kev

Hi Kev

I never got around to adding a relay to my first temp controller as it just looks after my fermenting fridge.

I've got a second fridge now and I want to set up a temp controller for this too. I've ordered an STC-1000 again as this works fine with 1st fridge.

Being a tight b@stard, on 2nd temp controller I want to make it capable of also controlling HLT temp when brewing, and as that's 3KW I'll need a relay.

Your circuit diagram is great and I know I'll need to adapt it for an STC-1000 but question I have is..

Does the relay get hot? (eg N24AW from Maplin)

Can I use a normal MB4 project box like the LH23A from Maplin or do I need something different to cope with relay heat?
TIA
John

[beermonsta]

mechanical relays don't get hot like that one (it's only Solid State Relays that get hot and need heatsinks)

[Kev888]

Hi John,

Yes Beermonsta is right - there is a tiny amount of heat generated by the mechanical relay's coil but not enough that you'd normally need to worry about it unless your ambient temperatures are unusually high - and if so then the STC would probably have similar issues. So those ABS project boxes look fine to me - particularly if its going to be of a reasonable size there should be more than enough air around the relay. (As he also said though, solid state relays are very different and need heatsinks and so on to handle any appreciable power.)

EDIT: by the way, the maplins relay is a slightly different configuration to the one used in my diagram. I forget the exact pins but the maplins one is more like this:

with a blade affair that moves across when the coil is energised, breaking a link between two contacts (which aren't used in this circuit) and making a link between the two others that we want.

Obviously take care, and the best of luck with it!

Cheers
Kev

[jmc]

Hi

Thanks for the advice, glad relay won't get hot.

I just need to check the STC-1000 will fit on the face of the maplins LH23A as I'm not sure it will be deep enough as internal depth of box is listed as 81mm so it might be a tight squeeze.

I'll measure STC-1000 on my current temp controller in the morning.

Cheers, John