# New Pid Controller Case Project



## fraser_john (11/7/09)

I have been sitting on this for ages, the wet & cold weather down here has given me a chance to get in the garage and get it started.....the work so far...

I have put panel connectors (green panel fittings) for the K-type thermocouples through the front of the case so I can stow the thermocouples when not in use.

There are override switches for the SSR's from the PIDs and the SSRs will have a normally closed (NC) SSR relay between the Mash SSR and the HLT SSR so priority will be given to the Mash heating element i.e. they both cannot be on at the same time and if the Mash element turns on, the HLT element turns off. Thanks to Kirem for this idea, cheers mate! Still pending on the NC SSR arriving, but everything is in place.

I have a 12v power supply in the cabinet and the top switch turns it on/off, I'll put a 12v bezel lamp next to the switch so I KNOW the 12v power supply is on and working. This is to provide power for the alarm and any other 12v requirements.

Top PID is the HLT PID and is a standard one.
Second row PID is the mash PID and is Soak/Ramp model.

John


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## Thirsty Boy (12/7/09)

Looks good Fraser.

I have my Mash-tun and HLT set up on a circuit similar to yours. I only have a single PID .. and its output is fed through a mechanical relay with two channels, one NO and one NC. The Mash tun comes off the NC side and the HLT comes off the NO side. So as you said, the HLT only gets power when the Mash tun doesn't want it. 

This means, and I assume you are doing it for a similar reason, that I am only ever drawing a maximum of 2400W. And my wife can put the kettle on while I am brewing without tripping out the whole house. 

Luckily for me, my HLT is a commercial urn.. so I am not using a PID. But I will probably get around to replacing the internal control with a more accurate and visible display unit eventually. I was thinking a simple on/off unit rather than a PID (or a PID set to on/off seeing as they are mostly cheaper anyway) - how much if any actual PID functionality do you think a PID unit would be able to maintain when it is only sporadically getting power??

Nice looking control box - I have future plans for that sort of thing.. but for the moment its all little jiffy boxes and a tangle of power cords. Sub optimal.

Top work

TB


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## hockadays (12/7/09)

Nice work Fraser,
I went the programable one as well and have played with the program side of it and it seems to be pretty straight forward to use. Can't wait to test it out on the full setup. I'd be interested to see how yours performs as well.


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## bulp (12/7/09)

hockadays said:


> Nice work Fraser,
> I went the programable one as well and have played with the program side of it and it seems to be pretty straight forward to use. Can't wait to test it out on the full setup. I'd be interested to see how yours performs as well.



+1 I've got the programmeable one too and it makes step mashing a breeze very happy with it. :beerbang:


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## fraser_john (12/7/09)

I went with the NC relay so that I did not draw more than 20 amps! My HLT element is a whopping 4600 Watts! So having both sets of elements would have tripped the breweries breaker, when I had the shed wired I put a seperate box in so that I would not affect the house.

The box I got from a guy in SA, cheap at $100, with $20 for freight.

As for programming the soak/ramp PID, groan, started looking at it once I got the power and SSR's setup today. My brain now hurts, looks like a PIA to get initial set up (alarms, power on mode etc). Not looking forward to all that reading.

I need to add some new pictures now the SSR's, heatsinks etc are all in.

Odd thing, I have the two bezel lights to show when the SSR's are on, seems the SSR's leak just enough voltage/current to activate them! So will have to replace them with 12v units instead. Bit of a bite. Also, using default setup for the PID, the alarm (AL1) light is on the PID, but my alarm is not firing, checked all the wiring and 12v power supply is working, so not real sure.....

John


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