HeaterMeter Homebrew Controller

[M Rochford]

Originally posted by Bryan Mayland:
Ah! I didn't even notice people had posted to this thread. Let me try and catch up.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M Rochford:
I am new to this forum and I am also working on a ethernet based thermo. I am curious to what resistor I should be using with the Maverick 73. I am currently using a trim pot to set it as close as I can to 22.1k resistance.

That depends on where you want your best sensitivity. If you look at this graph you can see how voltage at the divider changes with at various temperatures for 2 different resistors.

As you can see the 22k ohm starts to really lose precision at about 250F, which makes sense, this probe was made to go in a piece of food. With 6.8k you can go a little further, about 300F, with the tradeoff that you lose a little precision throughout the entire range. The standard HeaterMeter used in a linkmeter uses 10k resistors which seems to be a decent tradeoff. </div></BLOCKQUOTE>

Are you using the same equation than in the original heatmeter? http://tvwbb.com/eve/forums/a/...70072103/m/909108292

Sorry for all the questions. I really like your project and I am trying to figure out my own little homebrew. Thanks for replying.

-Mike

 

[Bryan Mayland]

Originally posted by M Rochford:
Are you using the same equation than in the original heatmeter? http://tvwbb.com/eve/forums/a/...70072103/m/909108292

Yes the formula is the same, but it looks a little different due to where the Steinhart and resistor values are stored:
https://github.com/CapnBry/Hea...er/grillpid.cpp#L125

 

[M Rochford]

Thanks again. I have a cookshack smoker and just looking at getting temps. So my board design is very simple.

 

[Dave Smith]

Scored a wishield off Ebay from the UK....so I can start building this when I get home from my shift on the ship in Jan.

 

[Dave Smith]

www.cutedigi.com
These guys have the wishield if anyone is still looking?

 

[Bryan Mayland]

Originally posted by Dave Smith:
www.cutedigi.com
These guys have the wishield if anyone is still looking?

Hi Dave, that board has been brought up as a replacement for the WiShield a few times now and unfortunately it isn't the same. They remove the DataFlash chip which means you don't have any storage for the web pages. (But they do add a LiPo charger circuit)

 

[Dave Smith]

DOH!!

 

[Daniel Cassady]

What's the story people?!?
This fell all the way to page 3!!!

It's the genuine smoking season, and nobody's reporting back on their ATC usage!?!?



Seriously though, how are everyone's cooks going?

 

[Bryan Mayland]

Originally posted by Daniel Cassady:
What's the story people?!?
This fell all the way to page 3!!!

The reason this is all so silent here is because we're all in The Dedicated HeaterMeter / LinkMeter subforum. Stronger than ever!