EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: BLF Lexel on May 09, 2019, 05:48:07 pm
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Hello,
as the 8845A does not have that feature build in the software I simply used the math with offset and multiplicator to get the temperature shown
it is in kOhms range, but the value represents 1:1 to °C
Used a cheap 2x3mm 100 Ohms 38.5K PTC
build myself a kelvin cable with detachable sensor cutting an USB cable in half
- cutting off the male USB plug
- female side has on the cut end to 4 banana plugs
- male side has the PTC soldered with 4 silicone leads as Kelvin probe
- so the actual cable resistance is eliminated
math can be also adjusted to calibrate the PTC in ice and boiling water
https://youtu.be/FFzoJUZd9ak
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[emoji106] Thanks for sharing.
Karsten
Gesendet von iPhone mit Tapatalk
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I think using a 100Ohm PRTD would be a better option.
They are supported by the 8845/46 for degc readout and are widely available for a couple of bucks (smd chip PRTDs).
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I think using a 100Ohm PRTD would be a better option.
They are supported by the 8845/46 for degc readout and are widely available for a couple of bucks (smd chip PRTDs).
I use a 100Ohms Platinum 3x4mm chip with 38.5Ohm/100K
the 8845A seems not to have °C option for them, or am I missing something?
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Apologies, I skim read your post and I misunderstood it.
I use the the terms NTC/PTC for thermistors and PRTD for platinum sensors - I thought you were using a thermistor not a PRTD.
And I was doubly wrong :-\ ..8845 doesn't have PRTD degc readout like the 8846, hence your post.
Hah, ignore me and carry on!