It is this time of the year again, when we build some more active TEC thermal chambers. I've managed to bring my resistance measurement capabilities to a magnitude better resolution and uncertainty, and this required additional chamber for cross-comparison measurements. Also needed to measure standards at different temperatures, so just one main chamber is not going to cut it anymore. Large chamber that I've shown last year is still mostly happy and working daily, but does require few minor improvements and fixes for discovered shortcomings. That will be story for another day, but today I'm showing lower power mini-TEC chamber built from scrap from megaTEC one.
Base material is same R13 50.8mm thick metallized foam board. Construction is also same, just boring box out of sheets despite some wierd aspect ratio this time.
You can tell that geometry was not my favourite subject in school. I don't care if it's look ugly, all that matters here is functionality and low cost/effort.
It's about a meter long, so deep devices such as Fluke 732A or Fluke 752A would have no problem fitting in. But most of time this chamber will just have passive resistors such as Fluke 742A, ESI SR104, L&N 42**, etc. in it.
Same foam board glue Loctite PL 300 was used to seal/glue walls together.
I have generously applied it on all corners and junctions to ensure airtight connection.
End cap walls for front and rear would be less thick with Foamular NGX panels + styrofoam.
Inner volume of result chamber happens to be 406 x 305 x 924 mm. Just enough to fit two ESI SR104, perfect result.
First victim size check:
Hopefully this weekend I can put 40W watercooled TEC unit, hook up
Arroyo TekPAC with
Raspberry Pi xDevs.com TECkit python datalogger/controller and get some logging to check stability.