Home Made Thermostat - Ts-040s

[user 384]

OK I finally got around to taking a picture of my home made thermostat. I started off by buying the thermostat "guts" from Tobins (http://www.tobins.com.au) part number TS-040S. It's a 0C-40C single pole double throw (SPDT) 16amp thermostat and comes with knob, bezel & screws. Next I went down to my local electronics shop and bought a general purpose outlet (GPO - 3 pin female plug), a box to house it in, and bulkhead for the electrical cord. I had a spare electrical cord laying around the house. I decided to get a fancy blue box just for aesthetics, but you could get a plain grey one cheaper,

Assembling the whole thing was dead easy. Drill 3 holes for the thermostat, one hole for the cord and one really big hole for the GPO. For the the GPO hole I drilled a pilot hole and then enlarged it with a grinding bit on a fake Dremel.

After the drilling you need to tighten 2 screws for the thermostat, one screw for the GPO and one bulkhead for the cord.

Attaching the wires was just as easy. The GPO has screws on the back to attach the wires, and I used spades to attach the wires to the thermostat. This meant no need to solder (which is good for me because I don't have a soldering iron).

For the capillary wire to fit into the box I just notched out a small groove and then screwed the box together. Job done !

It was made even simpler by following the wiring instructions that Justin posted (http://www.aussiehomebrewer.com/forum/index.php?showtopic=2160&hl=ts-040s&st=15).

Cost? $38.50 plus postage for the thermostat. Plus about $20 for the other bits and pieces. So all up about $60.

Best part about it? I feel pretty good that I knocked it up myself ! As a desk jockey I don't get a chance to actually make anything, so even though this was the most basic of projects, I really enjoyed doing it.

A big thanks to Justin for all the information.

Cheers
MAH

 

[Batz]

Well done MAH
Looks great , innovative bunch us AHBs

 

[dreamboat]

Sure looks pretty in the blue box.

How do you go for running the sensor into your fridge?

Or do you put the whole thing in there?


dreamboat

 

[Corey]

Yep - very nice MAH. You've almost inspired another desk jockey to give it a go.

 

[user 384]

Dreamboat

The capillary wire in the photo is wound up, but it's 1 metre long so easily fits in the fridge, withouth the need to put the box in.

Cheers
MAH

 

[Wax]

Looks great MAH. How acurate do you find it? What sort temperature range does it hold? I've heard of home made jobs that fluctuate up to 5 deg.

 

[user 384]

Haven't had a chance to give it a thorough test, but it has a 4 degree differential, so should swing 2 degrees either side of the set point eg if set at 20C it should switch on at 18C and off at 22C. Justin seems to be pretty satisfied with this theromstat.

The guts are a proper industrial theromstat, so there should be no problem. Tobins get them from Rainbow Electronics who have been around since 1987, and they export globally (http://thermostat.en.ec21.com/).

The only home made aspect is that I made up the housing. It's basically a GroWarm unit that a few HBS sell.

Cheers
MAH

 

[big d]

excellant job and posting mah.ive been thinking about buying one for awhile now and this has made me want to build one up myself as youve done.

cheers
big d

 

[user 384]

If you get some stuff sent from Tobins, think about ordering a few bits and pieces to spread the cost. I ordered myself and a mate, 2 thermostats and 2 heat sticks (part no 4108). Total cost to have delivered to my office in Adelaide was $15.

Cheers
MAH

 

[Justin]

Nice work MAH (especially the blue box ), looks the goods and glad to hear it all went together well.

I find my thermostat has a differential closer to about 3 degrees but as we have all said numerous times the temp of the liquid stays pretty much rock steady at your desired temp due to the size of the thermal mass (I like incorporating that term in, makes me sound like a nuclear physicist ).

For those people who are a bit pedantic these thermostats actually have a calibration screw on them so you can fine tune them in order to get the dial showing exactly the temp that the fridge actually is. Of course this doesn't really matter as you can just play with the dial until you get the right temp but hey if you want to play around and get it set up spot on it might be worth playing with.

For those interested or bored one day, the calibration screw is located on the back of the thermostat in the centre under a sticker. It is just a grub screw that gentle presses onto the diaphragm of the thermostat for fine adjustment. I'd be careful and only make fine adjustments with it so as not to damage the diaphragm by accidently tightening too far but it's there if anyone wants it.

Finally, a bit of credit should also go out to Linz as he was the bloke who firstly identified the thermostat to replace his Growarm one and started the ball rolling with finding someone who sold them. There are other thermostats about that do the job, but hey this one works just fine. Thanks Linz.

Did you wire it up for heat and cool options MAH?

Cheers, Justin

P.S. Those heat sticks rock.

 

[user 384]

Hi Justin

Nope , just for cooling. In Adelaide there is not that much need for heating. This winter has been pretty cold, but my house still stays about 16C even on the coldest days. Plus it will only be used to run my fridge.

I could easily switch it over to heating if I wanted, because the spades just slip on and off the thermostat terminals. As a beginer to building electronic do-hickeys I thought it best to keep it simple and not add an extra switch.

Cheers
MAH

 

[Tony M]

West Ausie people reading this-------All Controls in Belmont have these. I have purchased three of these from him over the last couple of years and he has always charged me $30.00 + GST. Two of these were close enough accurate, but I had to tweak one about 7C.
I noticed he also had gas rings in his shop but I didnt ask the cost.

 

[siiren]

MAH, where did you get the bits and pieces from?
I have ordered a TS 040S which should get here tomorrow.
Do you remember the dimensions of the box?
Cheers

 

[Justin]

Jaycar or Dick Smith will have all the fittings you need. My box is about 13-14cmX8-9cm off memory. You'll work it out. The thermostat isn't that big itself so the box size depends on what else you want to cram in there. eg. I put a switch in my box to allow heating or cooling.

Cheers, Justin

 

[Jase]

I decided to have a go and build one of these on Friday. I now have a chest freezer sitting beautifully on 2 degrees. :lol:

A big thanks to both MAH, for his photos, and Justin, for his step by step instructions.

Cheers,
Jase

 

[Jez]

Justin,

You said it's possible to wire this thermo to heat or cool with a switch?

Once again pardon my electronics ignorance but is this a manual switch you have to flick from heat to cool whenever you reckon it is needed or is it possible to wire something to switch automatically between heat or cool as required?

The heat & cool options sound like the best way to keep a consistent temp rather than just cool.

Jez

 

[Justin]

It's a manual switch. I just set it up so I could use the thermostat to heat OR cool (depending what I'm brewing and what season it is). The thermostat could be set up to have both a heater and a fridge set up, but the problem is that one or the other is going to be on all the time. This will give you a yoyoing effect in temp that is unnecessary, plus will consume more power and defineitely be harder on the fridge because it'll run more often.

Trust me on this one though. You don't need to have both a heater and a fridge hooked up. once you set up a fridge and get it running you'll see that the temp is pretty stable anyway. Plus by having a heater and the fridge hooked up your just going to be shortening the time between the upper and lower set point.

eg. Just fridge hooked up. Temp is 16C, fridge is off, say it takes 20mins to raise up to 20C. Fridge comes on for 5 mins and the temp is back down to 16C. fridge turns off.

eg.2 Fridge and heater hooked up. Fridge is at 16C (set point is 18C) so heater is switched on, 2 mins later the temp is 20C, heater goes off and fridge comes on, 5mins later temp is 16C, fridge goes off heater comes back on, the cycle continues.

In reality a heater and cooler is not necessary at the same time.

Cheers, Justin

Edit. Your fermentation temp wont vary this quickly, and in reality for an 18C ferment temp your probably aiming more at 16C in the fridge, especially if the ferment is very active. By placing the probe close to the fermenter you'll get the most accurate control on temp.

 

[Jez]

Thanks again Justin, I'm certainly learning heaps today!

Just got back from Jaycar with all my bits to build the external thermo. Can't wait to get it firing!!

Thanks for being so helpful to an obvious newbie

Jez

 

[Justin]

No worries mate, just remember to check your work and make sure all is right and be safe.

Cheers and good luck. It's nice to make your own stuff.

Justin

 

[ozbrewer]

any chance of some one postiong step by step with detaild pics?