theatrus' "Perfect Temperature Controller"

[MaddyP]

Following! Still haven’t decided on temp monitoring for my Node Red build.

 

[theatrus]

Proto boards showed up. 4 layer for simplicity

 

[mnl]

Looking good!

 

[theatrus]

Record temperatures, fires, covid, all part of the delays. Anyway, finally got a base built up to start testing with the prototype. Thats before the AQI plunged back to the 300s here in the valley and the unsealed garage workshop was abandoned for now.

Only SMT is mounted, and in the layout for the RTD sensors without external ADC (hence all the bottom unpopulated areas)

I didn't have a chance to fix my stencil printing setup for prototypes so I had quite a bit of lift off which over-pasted a few parts. I'll go clean them up before testing with power :)

Only 15 pins here to clean up :grimace:

 

[Aframereef]

Comming together. I haven't had time to work on any of my boards because i am working on rebuilding my old tank. Maybe this winter i will get back on it. Work just gets in the way of my hobbies.

 

[Ranjib]

Looking good @theatrus :-)

 

[theatrus]

First power on test. Interesting results, since I didn't actually check what _to_ expect. With zero firmware loaded, and zero sensors attached, the hard wired logic has decided that:

- The cooling output should be enabled.
- The safety disconnect relay should be tripped.

Which is actually encouraging from a failsafe standpoint. It does make sense, as the sensors missing means they are "infinite" resistance, which will just result in a max temperature signal. I wasn't sure what to expect with the programmable DAC and comparator, but it appears to actually power on in a useful state.

Note the LEDs are hard wired to the relay signaling - top is heat, next is cool, third is the safety relay disconnect enabled (though perhaps this actually should be an inverted signal), last is the alarm output (this is a software settable pin to make beeping noises).

 

[mnl]

Very nice. You have my sympathy on the soldering, SMT has never been my forte.

 

[User1]

Yeah - be safe. I believe I am near you and ash was falling from the sky similar to the opening scene in the Book of Eli movie when he was hunting the cat...

I only recently as of Sunday went out front to do yard work or work in the garage.

 

[Ranjib]

Yeah - be safe. I believe I am near you and ash was falling from the sky similar to the opening scene in the Book of Eli movie when he was hunting the cat...

I only recently as of Sunday went out front to do yard work or work in the garage.

I felts it’s more like Mordor or Isengard from lord of the rings, or a scene straight out of mad max