How to: Raspberry Pi HLT/Boiler Controller

Discussion in 'Beer Brewing "How-To" Guides' started by Robbo100, Jan 10, 2014.

Help Support The Homebrew Forum UK by donating:

  1. Aug 16, 2014 #101

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    I think it should be a number and not letters.

    I think it may be a row 0 vs row 1 issue.
     
  2. Sep 1, 2014 #102

    thear25

    thear25

    thear25

    New Member

    Joined:
    Aug 10, 2010
    Messages:
    11
    Likes Received:
    0
    Hi Guys, I've been glued to this thread for the last month or so and am finally in a position to start building and programming, which nicely coincides with filling my last FV on the weekend so there is a lovely window before the next brewday.
     
  3. Sep 2, 2014 #103

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    Excellent.

    Pacman has got his working, but for some reason has been banned from the forum.
     
  4. Sep 2, 2014 #104

    thear25

    thear25

    thear25

    New Member

    Joined:
    Aug 10, 2010
    Messages:
    11
    Likes Received:
    0
    Well that's not very good at all. Have many others managed to follow through the "how to" and get it working?
     
  5. Sep 7, 2014 #105

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    Yes, Pakman has, and seems to love it!
     
  6. Sep 9, 2014 #106

    thear25

    thear25

    thear25

    New Member

    Joined:
    Aug 10, 2010
    Messages:
    11
    Likes Received:
    0
    How did you guys get familiar with the raspberry pi in the first place, I'm getting everything in place now but looking at options of using some of the setup to monitor the beer when its not brewday!
     
  7. Sep 9, 2014 #107

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    I self taught.

    Basically, I had a project in mind, and then went out to make it happen. Lots of research and mistakes!
     
  8. Sep 30, 2014 #108

    brewman38

    brewman38

    brewman38

    New Member

    Joined:
    Mar 17, 2014
    Messages:
    4
    Likes Received:
    0
    Brilliant im in process of setting up and this is the best hopefully can follow it and build it brill
     
  9. Oct 26, 2014 #109

    yoyomet

    yoyomet

    yoyomet

    New Member

    Joined:
    Jan 9, 2014
    Messages:
    9
    Likes Received:
    0
    As I have 2.7Kw kettle elements I need over 10A. I've looked at the Beefcake Relay Control Kit referenced in 2.2 of the instructions but think a solid state relay such as the FOTEK Solid State Relay SSR-25 DA would be simpler - http://www.ebay.co.uk/itm/Solid-Sta...onents_Supplies_ET&hash=item3ce45f8c2bhttp://

    The question is, will the circuit in this design switch the SSR? The specs of the SSR say the Min. ON > 2.4V and OFF < 1.0V with a trigger Current 7.5mA / 12V.

    Thanks in advance for help on this.
     
  10. Oct 26, 2014 #110

    hulmea

    hulmea

    hulmea

    Andy

    Joined:
    Oct 2, 2014
    Messages:
    50
    Likes Received:
    6
    Location:
    Liverpool
    I wish I had seen these solid state relays before. I had to use a 2n7000 with old fashioned relays. These look a great idea.

    The only thing I would look out for is on start the PI can have a voltage on the pin at around 1V. I used a 10 K pull down resistor on my MOSFET to ensure it is not triggered.

    You may have to do the same with this relay to stop it turning on by accident. Once booted if will be less than 1V so it shoud be fine. When the pin is up it will be around 3.3v so that should be plenty to run this. let us know how you get on as i really fancy these.

    Cheers

    Andy
     
    yoyomet likes this.
  11. Oct 27, 2014 #111

    yoyomet

    yoyomet

    yoyomet

    New Member

    Joined:
    Jan 9, 2014
    Messages:
    9
    Likes Received:
    0
    Andy - thank you for the response. I'll be getting parts together and trying these relays over the next few weeks along with finishing the brewery build. I'll get back once I've go something to report (or another question!).

    Martin.
     
  12. Oct 27, 2014 #112

    Fil

    Fil

    Fil

    Landlord. Supporting Member

    Joined:
    Oct 17, 2011
    Messages:
    4,115
    Likes Received:
    975
    fwiw the 25a fortek SSR's available on ebay for a quid or 2 need 3-32vdc to drive them, and an arduino with a 5v hi on its gpio pins is ample to drive one. Just dont forget the heatsink and be aware even when off these can bleed a load current so further isolate anything fed by them when you want it OFF.

    Dont leave your elements dry and plugged into SSR control fed by a live current, they will bleed and your elements will start to heat up, not at a massive rate and will stay just hot to the touch for minutes but could if left unattended be a risk.
     
  13. Oct 28, 2014 #113

    yoyomet

    yoyomet

    yoyomet

    New Member

    Joined:
    Jan 9, 2014
    Messages:
    9
    Likes Received:
    0
    Fil - thanks for the heads up about the advice on the bleed - well worth knowing! You said don't forget the 'heatsink'. Do the SSRs get that hot? Should I stick a heatsink on each one?
     
  14. Oct 28, 2014 #114

    Fil

    Fil

    Fil

    Landlord. Supporting Member

    Joined:
    Oct 17, 2011
    Messages:
    4,115
    Likes Received:
    975


    I am using the standard 25a fortek ssrs found at bargain basement prices on ebay, under pid control heating my hlt to a sparge temp of 85C with 2 x 1.5kw elements powered through a single SSR i measured the temperature of the 1st fin on the heatsink under load with an accurate tip mounted probe at circa 60C

    [​IMG]

    you can just make out the probe (long silver thing) wedged in the heatsink..
     
    yoyomet likes this.
  15. Oct 29, 2014 #115

    yoyomet

    yoyomet

    yoyomet

    New Member

    Joined:
    Jan 9, 2014
    Messages:
    9
    Likes Received:
    0
    Thanks Fil - My load on each one will be 2.7Kw so I'll incorporate a couple of heat sinks
     
  16. Nov 2, 2014 #116

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    Hi all,

    Just to let you know, that I won't be supporting my Boiler/HLT/Fridge controller on this site anymore. If you have any questions, then I will be able to answer them on Pinventor.

    I hope the mods don't mind me linking to this other site - it is not a brewing site, so shouldn't be a problem.

    Cheers :thumb:

    Robbo100
     
  17. Dec 1, 2014 #117

    Robbo100

    Robbo100

    Robbo100

    Regular.

    Joined:
    Dec 21, 2012
    Messages:
    401
    Likes Received:
    21
    If you ever wanted to make a Raspberry Pi HLT/Boiler Controller, but didn't want to bother with sourcing all the components and wiring it all together, there is a new Raspberry Pi Add-On Board (called the Pi&Bash>_) which will do the job almost out of the box.

    All you would need to do is to connect your relays to the digital outputs, and add your thermometer chips to the GPIO4 output (or use the supplied analogue thermometers), and you are in business!

    The code would need tweaking, but it would be a pretty easy job to do. I might get one and give it a try!

    Details of the Pi&Bash>_ are here
     

Share This Page