explosion-proof thermocouple(thermal resistance)with temperature transmitter

http://www.ahdqjt.com     time: 10/22/10 09:47

it is usually connected with display meter, recording meter, computer, etc. to directly measure temperature of liquid, vapor, gas and solid surface ranging from-200 to 1300 with explosives such as hydrocarbon on production spot, with output of 4 20ma.

1.double wire system output 4 20ma, good anti-interference performance
2.spare cost on compensational wire and installation of temperature transmitter
3.safe and electric, with long life expectancy
4.automatic compensation at cold end, non-linear rectifying circuit

operation theory
explosion-proof thermocouple has a junction box of enough strength with gaps inside it. all spare parts which might produce spark, electric arc, and dangerous high temperature are sealed in the junction box. when explosion within the box happens, fire and high temperature caused by explosion could be extincted and cooled.
pyroelectric potential change tested with the thermocouple (thermal resistance) results in imbalance signal through electrical bridge of temperature transmitter. the signal transforms into d. c. 4~20ma signal after being amplified and is transmitted to display meter, then display meter indicates relevant temperature value.

main technical parameters executive standard