EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: eti on December 22, 2021, 10:00:11 pm
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Hello :)
Are all cheap DMM temp probes the same? I had to dispose of one, and I have a couple of other spares from cheap DMMs - the spare I have to hand is "TP Series".
Thank you and Happy Christmas.
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All DMM I know use type K thermocouple so you can use any type K thermocouple and it would be fine.
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All DMM I know use type K thermocouple so you can use any type K thermocouple and it would be fine.
Much appreciated, thank you and Happy Christmas!
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All DMM I know use type K thermocouple so you can use any type K thermocouple and it would be fine.
I'd say that in my experience most use either NTC thermistors or PT100 platinum resistance sensors. I'd say that on balance more 'cheap' multimeters use 10k or 100k NTC thermistors than thermocouples. The electronics for measuring resistance are already there, whereas thermocouples require additional electronics capable of amplifying the typical 1mV at room temperature of a type K thermocouple and cold junction compensation. PT100 sensors are more likely on decent bench DMMs, possibly as an additional alternative to NTCs.
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All DMM I know use type K thermocouple so you can use any type K thermocouple and it would be fine.
I'd say that in my experience most use either NTC thermistors or PT100 platinum resistance sensors. I'd say that on balance more 'cheap' multimeters use 10k or 100k NTC thermistors than thermocouples. The electronics for measuring resistance are already there, whereas thermocouples require additional electronics capable of amplifying the typical 1mV at room temperature of a type K thermocouple and cold junction compensation. PT100 sensors are more likely on decent bench DMMs, possibly as an additional alternative to NTCs.
Every DMM I've ever owned has been a thermocouple, and these definitely are those - a welded fused bead, and the leads are sheathed in woven fibreglass.
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Every DMM I've ever owned has been a thermocouple, and these definitely are those - a welded fused bead, and the leads are sheathed in woven fibreglass.
No doubt that's a thermocouple but I'd still contend that's unusual on cheap multimeters in my experience. It is bound to be type K, I've never seen anything other than type K on cheaper instruments.