Explosion Proof Thermocouple
Explosion Proof Thermocouple
(OP)
Good morning everyone,
I am currently tasked to buy explosion proof thermocouples for an oil refinery. I would like to know what defines an explosion proof thermocouple, as my head engineers told me that we only need to ensure that the thermocouple we buy is sealed up at points so that no gas can enter the terminal block, and that the head needs to be ATEX approved.
However, I am sure that there are more requirements to make a thermocouple 'explosion proof'.
Thank you in advance!
NICOLAS
I am currently tasked to buy explosion proof thermocouples for an oil refinery. I would like to know what defines an explosion proof thermocouple, as my head engineers told me that we only need to ensure that the thermocouple we buy is sealed up at points so that no gas can enter the terminal block, and that the head needs to be ATEX approved.
However, I am sure that there are more requirements to make a thermocouple 'explosion proof'.
Thank you in advance!
NICOLAS





RE: Explosion Proof Thermocouple
Thermocouples are intrinsically safe. Thermocouple READING devices such as transmitters, which are the only potential source of igniting energy in a thermocouple circuit, can be rendered intrinsically safe by design, or perhaps by the use of a zener barrier or the like. Or you can put the whole thing in an explosion proof head and not bother with the zener barrier. Typically, the transmitter itself comes with an explosion proof head.
This all assumes that your area classification is Class 1 Zone 0 or 1 (i.e. division 1)- normally hazardous. Most applications are NOT normally hazardous- they are typically Zone or division 2- hazardous only during an infrequent release event. In that case, explosion proof equipment is not required- nonincendive-rated instruments, without the requirement for the poured seal and clunky explosion proof box, can be used safely instead. That makes things easier to maintain, and usually cheaper.
RE: Explosion Proof Thermocouple
RE: Explosion Proof Thermocouple
RE: Explosion Proof Thermocouple
Some vendors are more skilled at providing the accompanying certs than are others.
RE: Explosion Proof Thermocouple
Please see the file attached.
cheers,
vlad