Brook's CraftBeer Pi Build Thread

[BGHSmt7]

Well. After quite a bit of reading, I decided to build a Raspberry Pi controlled brewing system.

I decided on using a 2-vessel system with a RIMS tube. However, I'm not using the standard RIMS setup with a heating element inside a tube. I'm following the idea of @weezy on the thread Thermal wire RIMS tube. I'll be building and wiring that up soon,

I've been following the CBPi facebook user group and the CBPi thread here on HBT and started procuring components. Many years ago, I helped build a CNC machine for a custom guitar builder. The computer finally bit the dust (pun intended) and needed to be replaced. I took the chassis and decided to use it as my controller case.

The following photos should help to showcase the progress of the build.

 

[BGHSmt7]

Continuing to improve it.

 

[matbtz]

Thanks a lot to show your control panel build.
I was looking to get some idea for do mine to.

I will be happy to see your hybrid-rims if you have the time to do some pictures and explanations, I check the topic of your link and that heating cable look good.

 

[BGHSmt7]

My pleasure. I keep figuring out things to do to improve the design of the setup. I'll be posting more photos soon. I should have some more indicator lights arriving Monday along with a contactor and another SSR w/ heatsink.

My plan is to have LED indicator lights for when the system is activating the elements and larger 22mm lights for when the elements are energized (working, overridden, damaged SSR).

I'm also going to re-wire the keyed switch to control the contactor and have it as a 220V shutoff with key safety.

The RIMS tube will be a stainless steel pipe with 1/2" NPT threaded ends attached to a 90 degree elbow on one side and a 'T' on the other. The other side of the elbow will be a 1/2" quick disconnect. The 'T' will have a temperature probe installed and a 1/2" quick disconnect to go back to the MLT. I got most of the hardware from brewhardware.com. If I was to order again, I'd get the SS tube from mcmaster-carr (This one)

 

[BGHSmt7]

BTW, if anyone's actually following the wiring... Yes, this system will be running 220vac, but there will be a 120V outlet with an IEC 320 that can be used instead if only using the pumps and RIMS tube and not the boil kettle.

 

[BGHSmt7]

Not a lot of progress this week. I was able to get my exhaust fan working and re-route some wires for the LEDs and switches. I'm planning on working on this build tomorrow. Tomorrow, I'm planning on installing the contactor for the 220v output, 5 SSRs, installing the element lights, and installing the temperature probe fittings. Hopefully I can get at least half that done

Attached is my horrible drawing ofmy wiring for my contactor for the boil element.

 

[matbtz]

Your drawing are not fancy but easy to understand for a French ��
Did you have link for the type of break out and the hotkey from your draw ?
And if you want to do a drawing of how to do the wiring for the led will be even better. I try to wire some led on the breadboard for show when signal is send to relay but nothing happen.
I guess your way to put the led after the relay is even better if they brake in open position.
Thanks mathieu

 

[BGHSmt7]

The power breakout board is from an old CCTV system that's 120VAC to 12VDC 5A with 9 terminals.
https://www.surveillance-video.com/power-supply-ps09dc.html

The key switch is from Auberins
http://www.auberins.com/index.php?main_page=product_info&cPath=32&products_id=277.

Since I will be using the Official CBPi shield, it will have a 12VDC output for the SSRs. I will be wiring the LED along with the output to the SSR (in parallel). That way, the LED will be lit with the CBPi software. I will have a different light for when the outlet is powered (That way if there's an issue with the SSR, it will let me know.

I'll try to draw something and post it when I get home later today.

EDIT:
The drawing that I posted is not quite exact to what I'm having to do. The contactor I bought will need 120VAC for the coil voltage instead of the 12VDC expected (I bought the wrong one. lol.) I'll ned to power it from one of the HOT legs instead of the power breakout board. Not bad, just a little different. I'll update that drawing as well.

 

[BGHSmt7]

Quit a bit of progress. Almost everything is wired and tested. Now I'm waiting on replacement SSRs and the CBPi shield to finish wiring. I'll be working on the RIMS tube soon too

As I was testing the indicator lamps, I saw that they were not working the way I wired them (inline). I moved a leg to neutral and they work great now! Funny how that works. Wire it right and it's good... (Doh!)

The contactor has been replaced with a 120VAC coil contactor and that's been wired and tested (It works great!)

During testing, I noticed that the SSRs I originally bought are not triggering as nicely as I want, so I'm replacing 4/5 of them (Argh!).

I was using the bandsaw and drill press with forstner bits and a half-round rasp to make the holes for the lamps. A forstner bit and a little sanding sponge made the temperature probe plate nice and easy.

I'm using a heatsink for each SSR and I've bolted each heatsink to the aluminum case. Should make them nice and secure along with the added benefit of extra heat dissipation.

You may notice on the temperature probe inputs, there are 7 3-prong and 1 4-prong plug. The 4-prong plug is for expansion. I figure that if I need more temperature probes, I'll wire them into an external box and use the 4-prong connector as a grounded dongle (+5v, VCC, GND, Box Ground). I can even use the 4-prong plug as a temperature plug if needed.

 

[BGHSmt7]

Even more photos of what I was able to complete last night and today

 

[BGHSmt7]

@matbtz here's an updated drawing of the indicator lamp and LED. The LED is before the SSR and is for when the SSR is supposed to be triggered. The lamp is after the SSR for a visual indication that the element is powered. There's a contactor between the SSRs and the outlet that allows me to kill all power to the kettle if I need/want to.

EDIT: I didn't draw it in the image, but the 3rd leg of the output jack goes to ground.

 

[helterscelter]

Very nice

 

[BGHSmt7]

Thanks!

 

[BGHSmt7]

Well, I had some time this weekend to work on the setup a little bit. I silver soldered the fitting on the end of the stainless tube for my RIMS tube, assembled the majority of the boil element from The Electric Brewery, and assembled the RIMS tube and figured a way to attach it to my kettle.

 

[BGHSmt7]

More Photos

 

[BGHSmt7]

Almost ready to brew! I just got notification that my CBPi Shield has shipped and I should get it Thursday. Once I get that in hand, I'll finish wiring the case and runa few tests runs with some dihydrogen monoxide to get the PID numbers and everything calibrated. I hope to be posting more photos and some videos soon!

 

[BGHSmt7]

Well, I thought I was making progress. Looks like there was some flammable substance on the heating element / ss tube.

View attachment 1495038918530.jpg

 

[day_trippr]

Did you dry-fire whatever that thing is?
I wonder if that woven braid has some fiber threads running through it...

 

[BGHSmt7]

I had, but just enough to test that it warmed up. Not long enough to see this. When it was smoking in the tube, it scared me. I let it burn off outside and it seems ok now. Just put me back some time.

 

[day_trippr]

Could you provide the genesis that led to this?
It doesn't look like anything out of The Electric Brewery...

Cheers!

 

[BrunDog]

IMO that tube is too small to have enough meaningful surface area to transfer heat across. Also with the double (or more) wrap, the outer band has nothing to sink heat into and will get hotter than the braid on the tube.

 

[BGHSmt7]

Could you provide the genesis that led to this?
It doesn't look like anything out of The Electric Brewery...
Cheers!

I'm using Weezy's Thermal wire RIMS tube design, only I'm using stainless steel instead of copper, and the 936w dual element instead of his 260w wire.

https://www.homebrewtalk.com/showthread.php?t=623646

IMO that tube is too small to have enough meaningful surface area to transfer heat across. Also with the double (or more) wrap, the outer band has nothing to sink heat into and will get hotter than the braid on the tube.

I'm not sure how much longer I should've made it. The heating element is wrapped about 15" long. According to the image posted by Weezy a few months ago, it didn't look like it was a very long run. I was testing it out after I burned all the nasty's off and I was about to get about a 30 degree change after a couple minutes running. Granted, there is quite a lot of heat loss right now through the insulation. I think that I'll have to change to copper pipe instead of the stainless. I was just trying to keep copper out of the equation, but my ss pipe is too thick I think.

 

[BrunDog]

No, I meant too small in diameter. The best solution would be a large diameter SS tube, blocked off inside by a concentric tube to take up space. That would be a bit tricky to make, but could be done ala DIY counterflow chiller style. You want as much surface area as possible to transfer heat from the wire/ribbon to the liquid. And/Or you could make it longer - you would just have to deal with the length of the overall size. You should avoid wrapping the heater over itself - that may cause it to burn up prematurely as the heat has no place to go.

Also, I would avoid copper, but that's me.

 

[BGHSmt7]

Yeah, I was going with the SS instead of the copper in Weezy's RIMS because I don't want to deal with the nasties of copper anymore. I don't understand the thermal properties and transfer of heat well enough to really design anything. I figured a 1/2" tube 17" long from brewhardware would be fine. https://www.brewhardware.com/product_p/sstubecustom.htm

I've finally got everything else in the build almost done. The CBPi Shield was delivered yesterday.

 

[BrunDog]

You could have a longer tube bent into a U shape, effectively doubling your length.

@augiedoggy uses a 3' cartridge heater - that's the best for effective transfer. Check out his build thread.

 

[BGHSmt7]

Even though I had the smoking RIMS, I was able to get quite a bit of the rest finished.

 

[BGHSmt7]

And still more progress

 

[BGHSmt7]

Installed the heating element and cord to the kettle as well as the temperature probe. Triple-checked the grounding. Then at the end of the day, let the heating element for the RIMS get nice and toasty outside. Then I re-flowed the silver solder for the fitting to make it a better solder joint and prettier.

 

[BGHSmt7]

You could have a longer tube bent into a U shape, effectively doubling your length.

@augiedoggy uses a 3' cartridge heater - that's the best for effective transfer. Check out his build thread.

3' is too long for my needs. I am unable to make a permanent installation so it has to me small-ish. I guess I'm looking for something like an external RIMS tube. I don't want to deal with another kettle like HERMS; nor do I want to directly heat the wort with an element like a standard RIMS tube.

I was looking at brewhardware.com and I'm thinking about emailing them to see if they can bend me a tube of 1/2" stainless 180 degrees and about 17" for each leg with NPT fittings on the ends. I'd then wrap the heating element figure-eight style around both legs. That should give me ~30" effective heating surface without wrapping the extra length around itself. It will also allow me to use the other components that I've already purchased.

 

[BrunDog]

That's a great idea. If you use camlocks they can solder on the male camlock fitting on too.

 

[BGHSmt7]

Unfortunately, I use ball lock QDs. My LHBS didn't have camlocks when I started purchasing the QDs and I slacked in the research department.

 

[golfindia]

Yeah, I was going with the SS instead of the copper in Weezy's RIMS because I don't want to deal with the nasties of copper anymore. I don't understand the thermal properties and transfer of heat well enough to really design anything

The thermal conductivity of copper is 20x that of stainless steel. Stainless is a sub optimal material for this application. To me, a short piece of copper as a RIMS tube poses zero danger.

 

[BGHSmt7]

Well, I redesigned and ended up with approximately 3 feet of copper tubing in a 15" length of 4" PVC pipe. The copper pipe was soldered into a triangle back and forth shape to fit the length. I wove the heater tape around the three legs. It was able to heat the water passing through fine, but the temperature inside the tube was too much for the PVC pipe. After a few minutes and getting the water from ~70* up to 160*, the PVC pipe was extremely hot to the touch, was supple, and was starting to melt.

I guess I will need to figure something else out.

 

[BGHSmt7]

Some photos of the RIMS tube components before I assembled it.

 

[BGHSmt7]

Here's the 4" x 17" tube completed. Kinda bummed that it is not going to work for me.

View attachment 1498042001889.jpg

 

[BrunDog]

Did you wrap insulation around the tube/heater to isolate the heat from the PVC tube?

 

[BGHSmt7]

Yup. As much ceramic insulation as I could fit. About 1" all the way around.

 

[BrunDog]

What was the total power? It sounds like the heat transfer into the tube was not effective. Theoretically speaking, if 100% of the heat were transferred, the max temp of the RIMs assembly would be the liquid exit temp. That would only be ~175 degrees.

Reading above, it sounds similar but PVC will soften at over 250 and melt at 320.

 

[BGHSmt7]

It's an Omega dual element heat tape http://www.omega.com/pptst/DHT.html

Model: DHT101060LD
25.4 mm x 1.83 m (1'' x 6'), 936 Watts, 120 Volts

The element does have a fabric sheath on it. I don't know if that's part of the issue.

EDIT:
I no longer have the heat tape wrapped around itself. It's wrapped around the copper as shown in the attached photo. I also spaced it along the approximate 12" length of the tubes.

Maybe I just don't have enough insulation around the element area itself. Maybe if I get a thicker tube, I could put more insulation between the element and the container. Or I could use a 4" HVAC duct pipe that wouldn't melt.. Yeah, it'll get hot, but I'm running outta ideas (and money).

View attachment RIMS Heat Tape Wrap Method.bmp

 

[BGHSmt7]

With my current wrapping method, I tried to get the most surface contact with the tape and the copper pipes.