If I burn down the house, SWMBO wont let me brew...

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Dr_Deathweed

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I got the Ok from SWMBO to make a fermentation chamber and I was thinking of one close to this. Now I ws thinking of building it a little longer and butting a divider in the center, with two individually controled temperature chambers. After some looking and ploting, I realised that I know enought about electronics to know when to ask for help!

I wanted to put the two fan/thermostat circuts in paralel off of one AC-DC converter. I was going to convert the thermostats to be remote sensing, but hook them into the same power supply. I know they run on 24V DC, and the fans are 24V DC. Am I overloking anything? The parts I am looking at are below.


transformer:
http://www.jameco.com/webapp/wcs/st...&catalogId=10001&productId=220960&pa=220960PS

Fans:
http://www.jameco.com/webapp/wcs/st...&catalogId=10001&productId=153411&pa=153411PS

Thermostat:
http://www.homedepot.com/webapp/wcs...d=10053&productId=100047225&categoryID=503549
 
I 100% agree. I mostly put the links up so people would know what parts I am looking at.
 
yes, PC power supplies are 12V, I did think about that briefly because I do have one just lying around. The problem with one of those are the thermostats run of a 24V heating/cooling system. If someone knows of a 12V thermostat, that would make alot of things easier....

As for the thermostats handling the amperage, I dont know, but I am glad you mentioned it. THe online specs didnt mention that, but when I get a thermostat, I will take that into consideration. The transformer i was looking at only ran at 1 amp, and the fans would be 2 280mA loads in paralell, so..... I don't know...:D

If anyone else knows a better way to rig a system like this up (for a little less would be best) let me know.

I will post a schematic of my original idea as soon as I get around to it....:cross:
 
Ok, it took every ounce of technical skill I have to come up with this schematic...
fermenter schem.JPG

in theory, would this work? what should I look out for/change? Once again, is there an easier way to do this? (temperature sensor/switch/magic?)

EDIT: oh, that sould read AC to DC..... my bad
 
Might be a little overkill, or not, but here's a pretty cool setup that would just as easy run a couple PC fans off a PC power supply. I just don't see a temp range listed. I also tried looking through Mouser's website, but wasn't coming up with too much there that was blow the 95-100°F range.
 
If you can find a junk PC, you could use the power supply and it may even have both fans you need.
You could just use bi-metal t-stats, should save you some $. I'm not sure whether or not you may burn the anticipator out of the thermostats or not. Thats a pretty minimal load, and they wont always be on together, I think Id go for it.
You may need to maintain batteries with a digital.
Most thermostats are not voltage sensitive.
 
I thought about bi-metal thermostats, but I was woried about temperature range in case I decide to lager in this. I think there are digitial thermostats that run off of batteries, and just act as a switch, but knowing me, I would forget to check them for a weekend-week-month.... Hence why I am trying to wire everything in.
 
Just checking some of the beginning links. Not so sure about replacing ice tubs in a fermentation box. Sounds like a pita.
I have thought it might be handy in summer and would also up my quality if I could maintain a 68 degree temperature. Unfortunately a freezer wont fit into the stairway leading to my basement.
I had the idea of using a bar fridges with a freezer in the top to pipe cold air from the freezer to the fermentation chamber using fans controlled by a thermostat.

Not sure if this might work?
BeerCanuck
 
you would have to find a way to do a return air supply to the freezer otherwise you would get a vaccum on one side and pressure on the other....., i think there is a thread about that around here somewhere.... I thought f somthing like that, but that limited where I could put this thing. Instead I am going to beef up the insulation and hopefully cut down on the ice changes to once or twice a week or so.
 
awsome, thats what I eeded to hear, thanks.

When I actuallly start building this thing, I will be sure to post that.
 
deathweed said:
yes, PC power supplies are 12V, I did think about that briefly because I do have one just lying around. The problem with one of those are the thermostats run of a 24V heating/cooling system. If someone knows of a 12V thermostat, that would make alot of things easier....

As for the thermostats handling the amperage, I dont know, but I am glad you mentioned it. THe online specs didnt mention that, but when I get a thermostat, I will take that into consideration. The transformer i was looking at only ran at 1 amp, and the fans would be 2 280mA loads in paralell, so..... I don't know...:D

Well, your selected thermostat "Works with most millivolt to 24 volt heating and cooling system." [sic] So I shouldn't worry overmuch about the voltage if you're considering using 12v parts. (Tangent: Aren't computer power supplies 5VDC?)

Amperage, I got no info, and that's really important. But the manufacturer's website might be of some assistance. Here's the site for the model you chose from Home Despot:

http://www.ritetemp-thermostats.com/8029B.html

Have fun!

Bob
 
thanks Bob, I will be trying to locate one of the thermostats this weekend and play with it a bit. Does anyone know what the amperage is on a heating/cooling 24V circut? that may answer our questions in a roundabout way...
 
ok wait, quick google search showed some other simmalar thermostats showed amp ratings between .18 and .75, this means I would be good with a 1 amp circut, or would I need something a little more since I will have 2 in paralell?
 
deathweed said:
ok wait, quick google search showed some other simmalar thermostats showed amp ratings between .18 and .75, this means I would be good with a 1 amp circut, or would I need something a little more since I will have 2 in paralell?
If your draw is 560mA, You would need a minimum of .56A rating, in most situations, you'd not want to accept the minimum. You should shoot for one in the .75 range.
It doesn't matter what your transformer(or PC supply) can produce as what it actually produces is determined by load. You may be cheaper out to just get a couple of relays and the cheaper thermostats.
 
5 Is Not Enough said:
If your draw is 560mA, You would need a minimum of .56A rating, in most situations, you'd not want to accept the minimum. You should shoot for one in the .75 range.
It doesn't matter what your transformer(or PC supply) can produce as what it actually produces is determined by load. You may be cheaper out to just get a couple of relays and the cheaper thermostats.
You still need a power source large enough to handle the load. Most transformers in the size range that he is looking for are sized in VA or volt amps. Watts are directly related to to VA through Olm's law and Watts law. So your sugestion of .75A is really a 75 VA transformer. So a transformer in to 100VA range would be as small as I would go. Keep in mind also that any thing else that is added to he line, like resistors or capacitors also add to this, that would also include his control. These are all areas of power loss. Door bell transformers work great, and they are cheap. It should also be noted that in this category of transformers a larger size might be cheaper as they are more common. S.
 
deathweed said:
I know they run on 24V DC, and the fans are 24V DC. Am I overloking anything? The parts I am looking at are below.

The thermostats don't run on 24V, they run on 3V supplied by batteries.

I'd run it on 12v as pc power supplies and fans are easy to find and inexpensive
 
Your correct lustreking, I just went out and got a thermostat to play with and it does run off of 2AAA batteries. I guess where I was getting confused is the statement "runs without batteries on 24V system" so I was trying to find a way to wire it in so I did not have to use/change batteries (not that big a deal i know)

Alright so I guess I dont have to worry about a 24V system anymore, and I do have a computer power supply lying around:
power supply.JPG

So, the questions now are:
1) If I am sticking to a 12V system, which of those wires do I use?
2) Is there a way to get a 6V supply to just solder leads to the battery terminals in the thermostat (still hopeful here :D )
 
deathweed said:
So, the questions now are:
1) If I am sticking to a 12V system, which of those wires do I use?
2) Is there a way to get a 6V supply to just solder leads to the battery terminals in the thermostat (still hopeful here :D )

1) I think the yellow wire is +12V, and the black is common

2) I'm not sure what you want 6V for, but if you're hoping to eliminate the battery (I wouldn't bother they'll last at least a year), you'll want around 3V.
 
lustreking said:
2) I'm not sure what you want 6V for, but if you're hoping to eliminate the battery (I wouldn't bother they'll last at least a year), you'll want around 3V.


Um, yeah, 3V thats what I meant to say...... derrrr
<-----moron:drunk:

As far as eliminating batteries, If I already have the power supply, why not? I think half the fun in brewing is learning the skills to build new toys. Of course as I pointed out above and as this entire thread testifies towards my electronics skills:
<-----moron:drunk:

Just hoping to learn more and get a fermentation chiller/intact homestead/intact marriage by the time it is all over:D
 
I started out with the intentions of using a computer power supply as a "temporary" solution on the fermentation cabinet I built. It's still there. :)

I had found the same link above when I was trying to figure out how to get mine to work. I'm sure that way works fine and is nice and pretty.

Here's a lazy man's way to get it to work:

Tie the green wire to any black wire. Plug in an old hard drive to one of the connectors. You're done.

Computer power supplies require a load to operate. The link above accomplishes this with a resistor, but a hard drive will work as well. (Again, this was supposed to be temporary until I purchased a more permanent power supply!)

You can pull off 3.3v with an Orange/Black pair... +5v with a Red/Black pair... +12v with a Yellow/Black pair, and a few others that I don't believe that I made use of.
 
jas0420 said:
I started out with the intentions of using a computer power supply as a "temporary" solution on the fermentation cabinet I built. It's still there. :)

I had found the same link above when I was trying to figure out how to get mine to work. I'm sure that way works fine and is nice and pretty.

Here's a lazy man's way to get it to work:

Tie the green wire to any black wire. Plug in an old hard drive to one of the connectors. Your done.

Computer power supplies require a load to operate. The link above accomplishes this with a resistor, but a hard drive will work as well. (Again, this was supposed to be temporary until I purchased a more permanent power supply!)

You can pull off 3.3v with an Orange/Black pair... +5v with a Red/Black pair... +12v with a Yellow/Black pair, and a few others that I don't believe that I made use of.


Oh thats awesome.... Here I was racking my brain about how to put this together with only what I have around the house, and BAM! There you go...

Damn school is rotting my brain... that or the beer... no must be school:mug:
 
Ok, I played around with the wiring and thermostat, and here is what happened:
1.JPG
This is the thermistor in the thermostat, I just desoldered the joints and pulled it out
2.JPG
I wired some 24 guage wire into where the thermistor was
3.JPG
and attached the thermistor on the other end of the wires. I had to play around with it a bit to get the polarity right so the thermostat would work, but other than this, and having very little soldering experience, this wasn't too bad
 
For the power supply, I attached some more wire to the terminals in the thermostat where the batteries go
4.JPG
and attached these to the orange 3.3V output and black ground on the computer power supply that I used jas0420's lazy mans modification on
5.JPG
yay for learning something new and not burning the place down! Next step, a second thermostat and the fans.
 
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