Home Brew Forums > Home Brewing Beer > DIY Projects > Fermenters > Multiple STC-1000 Controllers
Reply
 
Thread Tools
Old 01-16-2013, 07:26 AM   #1
jkmcd3
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
jkmcd3's Avatar
Recipes 
 
Join Date: Feb 2010
Posts: 50
Default Multiple STC-1000 Controllers

Hey Everybody,

I know that there are tons of STC-1000 wiring how-to threads out there, however I have a couple of specific questions around wiring up multiple, 2 in my case STC-1000s.

Below is a wiring diagram that I put together. I am not an EE, or even an electrician for that matter, so I will explain what I am trying to depict in the drawing:

I have a mini-fridge that I was using for serving, but I recently upgraded to a GE 5 CUFT chest freezer for serving, so moving forward I will be using the mini-fridge for fermenting. I plan to install 2 STC-1000s in a makeshift control panel. Each STC will be wired to 1-15 amp dual receptacle. A third 15 amp dual receptacle will be added and wired directly to the main feed for a "constant on". 1 of the STC-1000s and outlets will be used to power the mini-fridge (fermentation chamber) and the other will be used to power the chest freezer for serving. Each STC and receptacle will be wired identical as shown in the diagram. I plan on using the "constant on" receptacle to run 2-4" fans - 1 for the mini-fridge and 1 for the chest freezer.

The questions I have are below the diagram (I just realized as I was going to post this that the labels on the STC and the outlets in the diagram are flip-flopped, but I think it still gets the point across):



1. Can I run just one main line into the control panel (as shown in the diagram) and splice it to provide power to both STC-1000s? This essentially means that I could be running the mini-fridge and chest freezer at the same time through the control panel that is plugged into 1-15 amp outlet tied into a 15 amp breaker, that is responsible for the load of other lights and outlets in the house as well.

NOTE: The GE chest freezer is spec'd at 15 amps, I am assuming thats at the moment that the freezer turns on, probably does not run at 15 amps once up and running? GE just says 15 amps though.

2. Should I just play it safe and run 2 main lines in, one for each STC vs splicing one main between 2 STC-1000s? Even then, could I run the mini-fridge and chest freezer off of 1-15 amp dual receptacle that, as mentioned above, is tied into a 15 amp break? If both happened to turn on at the same instant could the sudden draw of power flip the breaker?

3. If I run 2 main lines, and the chest freezer requires ~15 amps, there is no need for me to put the inline fuse in place is there? Considering the circuit is 15 amps? Would the fuse blow before the circuit flips? If so the fuse could save some irritation of lights and other outlets going out if this setup happens to pull too much power.

4. Do I need to have a fan for the mini-fridge (about 4.5 CUFT)? If not, should I wire the main line into one of the outlets for my chest freezer receptacle (which would reduce my total receptacle count from 3 to 2)? As shown in the diagram I am wiring the heat up to one of the outlets but will probably not be using the heat, just the cool. Could I use the other as the "constant on" for a fan for the chest freezer?

5. Should I add ventilation to the control panel for the STC-1000s? I have read that they do not produce that much heat, however, here in the Texas hill country we can get consecutive days over 100 in the summer time, and I do plan to keep this setup outside on the back porch?

That is everything I can think of right now. My main concern is the power draw running the two appliances off of one 15 amp outlet that is tied to one 15 amp circuit.

I really appreciate any advice.

Thanks,

John


jkmcd3 is offline
 
Reply With Quote
Old 01-16-2013, 08:15 AM   #2
OCBrewin
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
OCBrewin's Avatar
Recipes 
 
Join Date: Jul 2010
Location: Orange County, California
Posts: 254
Liked 20 Times on 17 Posts
Likes Given: 4

Default

Does your freezer really pull that much juice? That's very surprising to me. I gave an older 5ish cf keezer that pulls 3 amps and a 7ish cf chamber that pulls less than 8. What you should really be concerned with is that those controllers are only rated for 10a and the mean it. I've burned them up Acer running just North of that after only 2 weeks off and on.


OCBrewin is offline
 
Reply With Quote
Old 01-16-2013, 03:39 PM   #3
reynolds5520
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2010
Location: Western Fingerlakes NY
Posts: 285
Liked 37 Times on 30 Posts
Likes Given: 16

Default

The 15 amps specified on the label may be the locked rotor rating of the freezer. It probably isn't that many amps in normal use - or even at starting.

Are you able to run both units on the same wall circuit now without tripping the breaker?

If yes, what you can do is use one 14 gauge power cord from the wall receptacle to your control box. Then use two 10 amp fuses in the control box to protect each controller circuit. You really do want a 10 amp fuse protecting each controller - the internal circuits aren't made to pass more than that.

Electrically, this is pretty much the same as if you built two stand alone controllers and plugged them both into the same duplex receptacle.


Yes, you can use the other half of a duplex receptacle for your always on fan circuit where you don't need it for the heat circuit. Since it won't run through the controller, that always on side doesn't need to be fused - but it does need to be wired with 14 gauge.


Ventilation of the enclosure can't hurt, given your high ambient temps on the porch.



Thinking about this a bit more, I would probably go with two separate control boxes so that I don't always have to keep the two units next to each other on the porch.
reynolds5520 is offline
 
Reply With Quote
Old 01-16-2013, 06:32 PM   #4
raouliii
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
raouliii's Avatar
Recipes 
 
Join Date: Aug 2011
Location: Ponchatoula, LA
Posts: 916
Liked 96 Times on 84 Posts
Likes Given: 133

Default

No need for two separate neutrals to each of the duplex outlets. Even if the tab is already broken, a short jumper is adequate.
__________________
On Tap:
Second Amendment Amber
Rearranger IPA
Ponchy Pale Ale - Falconer's Flight
NippleRub Ultra (Light Lager w/Mexican Lager yeast)

In the Chamber:
Empty - IT'S TOO HOT TO BREW

Next Up:
I SAID, IT'S TOO HOT TO BREW
raouliii is offline
hasbrew Likes This 
Reply With Quote
Old 01-17-2013, 06:31 AM   #5
jkmcd3
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
jkmcd3's Avatar
Recipes 
 
Join Date: Feb 2010
Posts: 50
Default Update

Quote:
Originally Posted by OCBrewin View Post
Does your freezer really pull that much juice? That's very surprising to me. I gave an older 5ish cf keezer that pulls 3 amps and a 7ish cf chamber that pulls less than 8. What you should really be concerned with is that those controllers are only rated for 10a and the mean it. I've burned them up Acer running just North of that after only 2 weeks off and on.
I am not sure I have not tested it myself. That is just what GE is saying that they recommend? Thanks for the heads up on the 10A on the controller!

Quote:
Originally Posted by reynolds5520 View Post
Are you able to run both units on the same wall circuit now without tripping the breaker?
Actually I have not tried yet, the chest freezer is still sitting all brand new in its box. I should obviously give that a try and let it run for a couple of days.

Quote:
Originally Posted by reynolds5520 View Post
If yes, what you can do is use one 14 gauge power cord from the wall receptacle to your control box. Then use two 10 amp fuses in the control box to protect each controller circuit. You really do want a 10 amp fuse protecting each controller - the internal circuits aren't made to pass more than that.

Electrically, this is pretty much the same as if you built two stand alone controllers and plugged them both into the same duplex receptacle.
Once inside the box can I splice a lower gauge off of the main feed. Say I run 14 in for my main can I / should I use 12 or 10 to the controller and to the outlet?

OCBrewin mentioned the 10A max as well. I will definitely protect these controllers with a 10A inline fuse as mentioned. I updated my drawing below to show 14ga feed with 2-10A inline fuses just before the controllers.

Quote:
Originally Posted by reynolds5520 View Post
Thinking about this a bit more, I would probably go with two separate control boxes so that I don't always have to keep the two units next to each other on the porch.
Yeah I thought about that as well. I actually considered too, to just install the units directly into the door/lid of the unit, but opted against that. I think I am going to move forward with the single box. I do not anticipate moving them too far from one another, but if I do I will remember you told me so!

Quote:
Originally Posted by raouliii View Post
No need for two separate neutrals to each of the duplex outlets. Even if the tab is already broken, a short jumper is adequate.
Assuming the same goes for the ground? I removed the 2nd feed of neutral and ground to each outlet and updated my diagram.

I really appreciate the feedback guys.

jkmcd3 is offline
 
Reply With Quote
Old 01-17-2013, 02:53 PM   #6
Huaco
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
Huaco's Avatar
Recipes 
 
Join Date: Dec 2011
Location: Just south of Cow Town, Tx
Posts: 1,302
Liked 124 Times on 77 Posts
Likes Given: 38

Default

I'm interested in this thread... I am building a 3-controller box right now. One will switch the chest freezer and the other two will control only heat for independent temp control of each of 3 vessels in my ferm chamber. (see signature line) I plan to post pix of the box once finished...
Huaco is offline
 
Reply With Quote
Old 01-17-2013, 03:46 PM   #7
leokatero
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2013
Posts: 8
Default

I am building a 3-controller box right now. One will switch the chest freezer
leokatero is offline
 
Reply With Quote
Old 01-17-2013, 04:16 PM   #8
Huaco
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
Huaco's Avatar
Recipes 
 
Join Date: Dec 2011
Location: Just south of Cow Town, Tx
Posts: 1,302
Liked 124 Times on 77 Posts
Likes Given: 38

Default

Quote:
Originally Posted by leokatero View Post
I am building a 3-controller box right now. One will switch the chest freezer
Is something missing? looks as though you were trying to quote me on this post...
Huaco is offline
 
Reply With Quote
Old 01-17-2013, 04:58 PM   #9
reynolds5520
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2010
Location: Western Fingerlakes NY
Posts: 285
Liked 37 Times on 30 Posts
Likes Given: 16

Default

Quote:
Originally Posted by jkmcd3 View Post
Once inside the box can I splice a lower gauge off of the main feed. Say I run 14 in for my main can I / should I use 12 or 10 to the controller and to the outlet?

Your logic is good in asking whether you can use a smaller wire. The next size smaller is 16 gauge (wire gauge numbers can be confusing - larger numbers are smaller wire) and capacity charts rate it to 13 amps.

So, you could use 16 gauge for all of the connections inside the box. Just make sure that you step down from the 14 gauge such that you fully split the loads. Don't share one 16 gauge neutral to all of the receptacles - run one to each. I hope I am making sense here - it would be easier to show on a drawing. In your drawing, the vertical lines representing the incoming power cord should all be 14 gauge. The horizontal lines that tap off of the vertical can be 16 gauge.

There isn't much difference in size though. If you can't find 16 gauge stranded type TFFN, THWN, or THHN, then just use 14 gauge. The 14 will be readily available.


On your drawing, it looks like you are ready to build this properly. To help someone that comes along after you and wants to use your drawing, there are a couple of things that would help with clarity.

1. In a U.S. standard 15 A 120V receptacle, the smaller of the two blades is the hot side, and you properly show the switched current running to the smaller blade of the receptacle. But, the small blade should be on the right side rather than the left.

2. You don't need to show ground and neutral wires to each half of a duplex receptacle since they are built in. But for clarity in the drawing, you could make a box around the two halves to show that it is one duplex receptacle and then show the internal connection tying the halves together. (A small modification of the bubble around the receptacles that you have there now, more like your original.) That way nobody will get confused.



edit: I just looked again at your drawing. The unswitched fans receptacle should be all 14 gauge - since it isn't on the fused 10 amp circuits.
reynolds5520 is offline
 
Reply With Quote
Old 01-24-2013, 12:08 AM   #10
jkmcd3
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
jkmcd3's Avatar
Recipes 
 
Join Date: Feb 2010
Posts: 50
Default Think I Got It

Thanks Reynolds for all the help. I think I got it now. Here is the updated drawing:



Sorry to be short but I am out of town on business the rest of this week so this project is on hold until this weekend. But once finished I will post some pics.

In the mean time here is what I was able to get done before I left. Couple pics of all the parts and the case cut and mocked up:





jkmcd3 is offline
 
Reply With Quote
Reply


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Multiple Burners Multiple Tanks oakbarn Equipment/Sanitation 1 08-28-2012 03:03 PM
Temperature controllers. KarlHungus76 Equipment/Sanitation 11 07-29-2012 12:39 AM
Temperature Controllers wulfsburg Bottling/Kegging 9 07-11-2012 10:21 PM
temp controllers and multiple ferm wraps jbeukelman Equipment/Sanitation 7 09-21-2011 01:25 PM
Love Controllers LooyvilleLarry Other 5 11-21-2008 06:20 PM


Forum Jump

Newest Threads

LATEST SPONSOR DEALS