Pyrometer Tales...

[backroad]

Anybody every heard that a pyrometer thermocouple is specific for either post turbo OR pre turbo. I've got a shop here in Dewey, Az that says the thermocouples are NOT interchangable in position. It seems to me that their only job is to read the exhaust gas temperature no matter where it is placed.

 

[Steve St.Laurent]

There are different types of thermocouples based on temperature range, materials, etc. A table can be found here - http://ts.nist.gov/ts/htdocs/230/233/calibrations/thermodynamic/thermocouples.htm . However, for our application pre or post turbo the temperatures are in the range of a K type thermocouple which is what all the pyros that we use require. So the answer is for the application you're looking for (pre or post turbo on a diesel engine) you want a K type thermocouple - no difference between pre or post.

 

[backroad]

Thanks Steve... I know that when I bought my Autometer Pyrometer there were actually two choices but they had nothing to do with the mounting location. One was a standard and the other was a racing one, which I assumed, meant that it was more HD and faster responding. I did buy the one listed as "racing".

It still strikes me very funny that a diesel shop would say such a thing and truly believe it.