I pulled a thermistor from a keurig coffee maker. It appears to be an NTC as it measures 52.2K at 73F and 33.2K when I warm it with my fingers for a few minutes. It has the markings "2511 1922" on it. I've googled quite a bit and have came up with nothing. I'm looking for a datasheet on it. Does anyone have an idea on what the numbers might mean?
The housing might be some kind of standard:
73F = 22.8 °C
Even when the picture is not exactly the same, it is probably compatible with a 50k TR-H87-1 NTC thermistor with the specifications: R25℃ = 50 kΩ ±1%, B25 / 50 = 3950 kΩ ±1%.
They might be made specifically for the coffee machine, and perhaps there was no need to put a brand or a type on it. Perhaps it is a cheap thermistor without brand. The numbers could be a date (week 25, 2011), but I assume that they are just some kind of production numbers.
Thank you! That's a big help!
I assume you are you looking to repurpose the sensor?
The best you can do is calibrate it. Measure resistance in boiling water and in melting ice for your 0° and 100° points; that should make for a great start. You can get an easy third temperature by measuring current room temperature and the resistance of the NTC at that temperature. With those data points you can fit the NTC curve.
At sea level with demineralized water.
I happen to live at sea level and I had some bottles demineralized water. So I tested it with a DS18B20 and it was accurate. I did not test it with normal tap water, but I read that it could make a difference of 1°C.
Distilled water is easy to find in supermarkets. As long as you know your elevation you can easily compensate for the air pressure difference.
1°C sounds like a lot to me just from the minerals in tap water, but it of course depends a lot on how hard your tap water is. For me it's very soft, and not likely to affect such a measurement much.
wvmarle:
I assume you are you looking to repurpose the sensor?The best you can do is calibrate it. Measure resistance in boiling water and in melting ice for your 0° and 100° points; that should make for a great start. You can get an easy third temperature by measuring current room temperature and the resistance of the NTC at that temperature. With those data points you can fit the NTC curve.
Repurposing for sake of learning yes. Thank you!