soma
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problem with thermocouple thermometer
I recently got a thermocouple thermometer from ebay (doubleways co.). It has a type K thermocouple and the thermocouple package says it can go up to
700C.
I want to heat up MgO to around 700C - 850C.
I tried heating up a layer of sand that was about 1" high. The gauge goes up very slowly and the wire and plastic housing is getting too hot. I think
it's going to melt long before the gauge gets to 700C.
Would the gauge go up quicker if the metal probe is more submerged?
Thanks.
[Edited on 31-8-2016 by soma]
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Magpie
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Please show us a picture of this instrument.
The single most important condition for a successful synthesis is good mixing - Nicodem
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Praxichys
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In my experience, any type K rated much beyond 300°C has no plastic components at all. Typically thermocouple readers can read the full range of a
type k (~1350°C) but the probe they ship with is only rated to about 300, despite what is said on the package. 850°C is bright-orange heat. Anything
plastic within six inches is going to be destroyed.
For pyro applications, I have had good luck with these:
http://www.ebay.com/itm/3m-Stainless-Steel-Probe-K-type-Sens...
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zwt
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Quote: Originally posted by Praxichys  | | Typically thermocouple readers can read the full range of a type k (~1350°C) but the probe they ship with is only rated to about 300, despite what is
said on the package. |
^ This.
As an example, here is the disclaimer on one I purchased: | Quote: | | Note: The thermometer itself can sensor 1300°C, but the 2 test probes can only test the temperature up to 250°C |
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soma
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This is the ad for it on ebay.
http://www.ebay.com/itm/231140593406?_trksid=p2057872.m2749....
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soma
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I tried putting the metal end of the probe in a gas flame and it went up quickly past 300C without the plastic getting hot.
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soma
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Looks good but I would need an adapter to connect it to this gauge.
http://www.ebay.com/itm/231140593406?_trksid=p2057872.m2749.
[Edited on 31-8-2016 by soma]
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soma
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I got the thermocouple you mentioned. I was able to scavenge some metal prongs from an adapter that came with the gauge and connected the leads from
the thermocouple to them. (It wouldn't fit into the adapter though). Does each lead need to plug into a specific slot, or can either lead plug into
either slot?
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Melgar
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You can plug either lead into either slot. You'll have a 50/50 chance of getting it wrong, in which case it'll be pretty obvious what happened when
you stick it into something hot and the temperature drops. In that case, just swap the wires again and you'll be fine, no harm done. There are often
color standards, but they vary enough based on locality and manufacturer that it's easiest just to try it and see.
[Edited on 1/8/17 by Melgar]
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