Newest Threads

**carlisle_bob** · 06-12-2012, 04:45 PM

Hi

First choice is open frame or wall wart. A lot depends on how you are going to mount the gizmo. For wall wart's your junk box is the first place to look. For open frames I usaly check eBay and Mouser.

You never quite know where a project is going to wind up. If the final install will accomodate an open frame, I'd go with somethig that puts out +/- 12 V and +5. Something around an amp on the +12 and a few amps on the +5.

I like the +12/-12 for analog suff like op-amps. The +12 is good for a wide range of relays. +5 will get you all the digital stuff like +3.3, +2.5, +1.8 and +1.2.

Of course if the power supply starts to cost more than the rest of the setup, something is not quite right. I generaly don't spend over $10 or so on a supply.

Bob

**Eighty2Fifty1** · 06-12-2012, 06:06 PM

Just placed an order for the 4-relay shield and 10 DS18B20's. (Doesn't hurt to have extras.) Now I'm off to Radio Shack to pick up an Uno and start playing with it.

**carlisle_bob** · 06-12-2012, 09:42 PM

Hi

Plug it all into a wall wart off an old USB hub and you'll be up and running in no time.

Bob

Rbeckett · 06-12-2012, 10:42 PM

Quote:

Originally Posted by Eighty2Fifty1

Just placed an order for the 4-relay shield and 10 DS18B20's. (Doesn't hurt to have extras.) Now I'm off to Radio Shack to pick up an Uno and start playing with it.

Arduino, Picaxe, Picbasic, basic stamp and many others are readilly available nearly everywhere. They are a ton of fun to tinker with and program too. If you have a little time you might have a look at the All About Circuits site and see some of the cool stuff those guys are whipping up. Most of it is still above my skill level, but I am catching up, slowly but surely. Lots of great info in a huge well written text that will help you develop circuit reading and building skills as well as MCU and PIC programming. Have fun, Arduino is pretty neat and is also not too steep of a learning curve either.
Wheelchair Bob

**carlisle_bob** · 06-13-2012, 12:50 AM

Quote:

Originally Posted by Rbeckett

Arduino, Picaxe, Picbasic, basic stamp and many others are readilly available nearly everywhere. They are a ton of fun to tinker with and program too. If you have a little time you might have a look at the All About Circuits site and see some of the cool stuff those guys are whipping up. Most of it is still above my skill level, but I am catching up, slowly but surely. Lots of great info in a huge well written text that will help you develop circuit reading and building skills as well as MCU and PIC programming. Have fun, Arduino is pretty neat and is also not too steep of a learning curve either.
Wheelchair Bob

Hi

I'd toss an Intel Atom motherboard into that list. Cost and power are a little higher, but not massively so. You wind you with major power to do what ever you want. No problem running a full blown OS and a high def TV for a display....

Bob

budsandsuds · 06-13-2012, 01:25 AM

Hi Eighty2Fifty1

I recently completed a mechatronics project for school using an Arduino Uno to heat and cool a son of a fermentation chamber I built. The cooling is done with the usual fan/ice method.

My initial thought was to use lightbulbs for the heating portion, however, I found flexwatt from this site http://www.bigappleherp.com/Flex-Watt-Heat-Tape and think it works great. I think I purchased from a cheaper supplier. I can get the chamber and 5 gallons of liquid up to 100˚F from 65˚F overnight on full power. The PWM pins work great if you want to hit a specific temp and maintain it...little bit of trial and error with that. Great if you're in the basement/garage or using lacto cultures or something. I used one of the cheap Fotek SSRs for this, like $10 on amazon and cheaper on Ebay if you don't mind the wait. The flexwatt only pulls about 40W and like 3A so it is pretty energy efficient compared to the bulbs.

For temp sensing I used TMP36s which you can find at SparkFun and they are really inexpensive and easy to setup and get working. The project now stands alone and has buttons to increase and decrease the set temp and has and LCD display for read out of set and actual temp and whether the fan/heating element is on.

I knew nothing about microcontrollers before beginning on the project so I kept it pretty simple and added different components in stages. Sounds like you're doing a similar project with similar experience so let me know if you would like any help with code/setup/ideas etc. No ethernet yet, but that's my next step.

Just my $0.02. Best of luck and have fun!

budsandsuds · 06-13-2012, 01:27 AM

Sorry that should be 1/3A not 3A. Sorry for the double post.

**Eighty2Fifty1** · 06-13-2012, 05:34 PM

Do you wrap the fermenters with the tape or just line the walls with it. I'm not 100% committed to a heat source yet, but I did buy my arduino uno yesterday and was able to blink the hell out of an LED.

Rbeckett · 06-13-2012, 10:16 PM

If you can blink LED's your not far from temp control. Just a couple sensors, and an LCD or two and your good. Have fun.
Bob

**carlisle_bob** · 06-13-2012, 10:41 PM

Hi

If you have grown up after electronics stopped being a vacuum tube thing - be careful when working with power switching. I see a lot of people being a bit careless because all their working lives have been with stuff that won't "bite you".

Bob