heatseeknyc / hardware

pcb designs
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calibrate v0.5 cells at multiple temperatures #7

Open hrldcpr opened 8 years ago

hrldcpr commented 8 years ago

We should write down times and temperature readings from the HPD-approved thermometers that correspond to specific times and readings from a few v0.5 cells, at a few different temperatures.

This will allow us to construct a voltage-vs-temperature curve for the v0.5 cells, and to see how consistent readings are between different cells.

(It would be nice to have a few v0.3 cells also involved, because more data is merrier, but that's less crucial.)

williamcodes commented 8 years ago

I'm doing my testing in the office now. It's going to take several hours since it reads hourly but I'll periodically update this comment.

http://relay.heatseeknyc.com/hubs/0013a20040bf9f8d

Version Extech Taken At Cell ID Temperature Sleep Period Received At
v0.3 74.3º 2016-01-11 16:25:20+00:00 0013a20040c17e69 74.39° 359000 2016-01-11 16:25:36.930578+00:00
v0.3 73.9º 2016-01-11 17:25:20+00:00 0013a20040c17e69 73.81° 359000 2016-01-11 17:25:24.022598+00:00
v0.5 71.9º 2016-01-11 21:34:52+00:00 0013a20040dc273e 112.13° 359000 2016-01-11 21:35:00.083369+00:00
v0.3 71.9º 2016-01-11 21:34:51+00:00 0013a20040c17e69 72.06° 359000 2016-01-11 21:34:56.954531+00:00
v0.5 57.2º 2016-01-11 22:34:52+00:00 0013a20040dc273e 117.35° 359000 2016-01-11 22:34:58.803825+00:00
v0.3 57.2º 2016-01-11 22:34:51+00:00 0013a20040c17e69 61.03° 359000 2016-01-11 22:34:55.731795+00:00
v0.5 90.6º 2016-01-11 23:34:51+00:00 0013a20040dc273e 104.58° 359000 2016-01-11 23:34:55.757785+00:00
v0.3 90.6º 2016-01-11 23:34:52+00:00 0013a20040c17e69 86.0° 359000 2016-01-11 23:34:59.023889+00:00
williamcodes commented 8 years ago

I wasn't able to simulate extreme temperatures very well. Without a proper thermal chamber, the best I could do was introduce a heating / cooling element into the box. I used an ice pack and hot water. This introduces a lot of variability within the same zone. @qelloman offered to let us use the thermal chamber at Columbia, hopefully that will improve this data.

hrldcpr commented 8 years ago

Cool thanks! I'll see if I can use this to better calibrate the v0.5 cells when I'm back in NYC at the end of the week.

If you want to do more testing without going up to Columbia, you could just put a cell outside, that would be extreme enough.

williamcodes commented 8 years ago

Man, I can't believe I let this go 15 days, my apologies, we've been totally slammed. Anyway, Noelle was able to get some good readings both on her fire escape and on her desk above her radiator. Here are the numbers:

short code time version temperature
786a 8:30pm v0.3 44.77
c509 8:30pm v0.5 127.23
Extech 39240 8:30pm v0.3 44.2
786a 9:30pm v0.3 44.19
c509 9:30pm v0.5 127.81
Extech 39240 9:30pm v0.3 44.19
786a 11:30pm v0.3 88.9
c509 11:30pm v0.5 102.26
Extech 39240 9:30pm v0.3 88.1