2 ms·
I once wanted to measure the temperature dependence of some electronics component. Aha, I thought, I don't need no oven or such fancy things, I will just do my
by maho 12y ago
I once wanted to measure the temperature dependence of some electronics component. Aha, I thought, I don't need no oven or such fancy things, I will just do my measurement while cranking up the room temperature, which I can record with a thermocouple!
I wondered why the thermocouple always returned to the same "room temperature" after half an hour or so, even though I and everyone else began transpiring heavily. It took me embarrassingly long to realize that the thermocouple only gives you the temperature difference between the two points of contact (tip and inside multimeter), and the multimeter took half an hour or so to warm up.
- cnvogel 12y agoThere must be a reference temperature sensor near the "cold junction", where the NiCr-Ni thermocouple wires are terminated. Remark: The external temperature probe is always called "hot", the reference junction always "cold", even if you measure liquid nitrogen with your sensor... If the "cold junction" is just the banana-plugs, then it's obviously not too easy to get a reading of the temperature there. Better devices will use these rectangular thermocouple-sockets (a rectangular block with two small, dissimilar, slots) and have proper NiCr-Ni cabling inside, just up to the termination point on the PCB, right adjacent to the voltage amplifier/sensor for the reference temperature.