Beginnings Of Mad Scientist Home Brewing

[brendanw]

Hi, I've been inspired by this forum over the last couple of months to make the jump into all grain.
So far have got the mash tun (esky with ss braid) and half the HLT / boiler done. but no pics of these atm (will have some in a few days when i get back to my brew buddys factory). But just thought id tell you guys ive finished my tempcontroller for HLT / fridge. its based off the one from craftbrewers http://oz.craftbrewer.org/Library/Gear/AWi...mpControl.shtml (please dont follow that schematic it wont work properly if anyones interested ill draw one up that works.)
so some details, it goes from -3 to 105 degrees works for heating and cooling, uses a 20A solid state relay to switch one of the 240v lines (kettle elements) and both 240v inputs are able to be controlled on the box. Temp probe is mounted in a 45cm piece of Al tubing.
Will try it out soon hopefully.

Cheers.
Brendan

 

[spog]

hhmmmm,niice. :beerbang:

 

[mika]

Very nice... keep us up-to-date. Many more out there looking for guidance and if you know what you're doing with that elec-trickery stuff.. post the schematic and some photo's of the unit.. then most importantly... tell us what you would do differently next time

 

[brendanw]

I know a bit of electronics stuff and will be learning more in the next few years (studying electronic eng).
I cant really take any photos of the inside of the unit as its pretty crowded inside and I didnt take any photos before id finished .
its all inside an old pc power supply case so its about 14*15*9 cms and the circuit itself is only 6*4 cms + regulator circuit which is a little smaller, all up i think it came easily under $30 maybe 25.

Heres some schematics for anyone interested, the power supply is probably a bit overkill, I just used something i had lying around and added the regulators to it.

and heres the temp controller schematic, the setting 2k resistor and all the switches were mounted on the case everything else was on the circuit board.
hope this helps

I dont think theres much id change but ill see what i think once i do a few brews.

 

[Jye]

Nice one Brendan

I did some thing similar here and it fitted nicely behind the light cover, its now in a separate box as an external thermostat. Electronic eng will allow you to steal... I mean borrow heaps of cool stuff for your brewery

 

[Batz]

Little like tidalpetes xmas case

Mad Scientist bit anyway

Batz

 

[Airgead]

Heres some schematics for anyone interested,

Brendan

Just out of interest, what changes did you have to make to the original design? I'm currently working on my own version of that circuit (upgraded to have 4 probes and relays). I worked it through and the original looked pretty sound to me (but it has been 10 years since I did any electronic work so I'm a bit rusty).

Where did you source your LM335's? I'm finding them tricky to get hold of. I am after the A series (the good ones) I think tricky dicky carry the normal ones but I would rather the extra accuracy.

Cheers
Dave

 

[brendanw]

Dave

It was mainly wrong resistor values for the temp setting part took me a little while to figure out why the temp setting was only giving me -1.21v or something on those lines. the resistors he used would be fine if you didnt use an lm335 and have the 2.7315v to negate the degrees kelvin. Nothing major but will save anyone a headache trying to figure out why its not working.

I got my lm335 from rockby (www.rockby.com.au) they are in clayton in melbourne have some great prices (not affiliated etc) , but only carry the z.
You dont need to use a quad opamp either a dual or 2 singles would do but i got them very cheap.

good luck with building it.

Brendan

 

[peas_and_corn]

It's good to see another brewer going AG! I am going to go AG soon, but still need some equipment...

 

[Airgead]

Dave

It was mainly wrong resistor values for the temp setting part took me a little while to figure out why the temp setting was only giving me -1.21v or something on those lines. the resistors he used would be fine if you didnt use an lm335 and have the 2.7315v to negate the degrees kelvin. Nothing major but will save anyone a headache trying to figure out why its not working.

Quite right. the original used the kelvin sensor didn't it.

I got my lm335 from rockby (www.rockby.com.au) they are in clayton in melbourne have some great prices (not affiliated etc) , but only carry the z.
You dont need to use a quad opamp either a dual or 2 singles would do but i got them very cheap.

[post="111547"][/post]​

I'm building 2 of these - one for the brew stand the other for the fermemters. I'm stripping out the range change switch and hardwiring the brewstand one to 50-100C and the fermemter one to 0-30. 2 sensors for the brewstand (mash tun and HLT), one relay to switch 15A for the HLT. For the fermenters I will have 4 sensors (2 fermenters, one CC enclosure and one to monitor the temp of the ice bath I use for chilled water) and 4 low power relays to drive the pond pumps I use to circulate the chilled water.

Rockby do have good prices on the 335's don't they. Unfortunately once you throw in freight to Sydney its cheaper to pick them up locally. I found the A's in the RS catalogue but at $30 each I can live with the z's.

Cheers
Dave

 

[cubbie]

Fair Dinkum I have no idea what you blokes are talking about!


I know I pulled the old thermstat out of my fridge and put in a new one. It was like plugging in a cord