The thermocouple with temperature transmitter is also called Integrated thermocouple with built-in temperature transmitter refers to that the amplification and transmission module (i.e. temperature transmitter) is installed in the waterproof or flameproof junction box of thermocouple, which is connected with the sensor to form an integration. It can output standard 4-20mA current signal or 0-5V or 1-5V voltage signal.It is usually used with display instrument, recording instrument and electronic computer to directly measure the surface temperature of liquid, steam, gas medium and solid in the range of 0-1300 degrees in various production processes.

■ Integrated thermocouple with built-in temperature transmitter features:

two-wire system with output of 4 ~ 20mA, strong anti-interference ability, saving the cost of compensation wire and installation of temperature transmitter, large measurement range, automatic temperature compensation at cold end and nonlinear correction circuit.

■Integrated thermocouple with built-in temperature transmitter working principle: 

the change of thermoelectric potential measured by thermocouple in working state will generate unbalanced signal through the bridge of temperature transmitter, which will be converted into 4 ~ 20mA DC electrical signal to the working instrument after amplification, and the working instrument will display the corresponding temperature value.

■ Integrated thermocouple with built-in temperature transmitter executive standard:

IEC584  JB / t7391-1994 

■ Integrated thermocouple with built-in temperature transmitter characteristic:

output signal: 4 ~ 20mA, load resistance 250 1 / 2, transmission wire resistance 100 1 / 2 

output method: two wire 

system tolerance level: 0.10.20.5 

power supply: 24v.dc ± 10% 

protection level: IP65 

insulation resistance: insulation resistance between instrument output terminal and shell shall not be less than 50 1 / 2 

Integrated thermocouple with built-in temperature transmitter thermal response time:

When the temperature step changes, the time required for the current output signal of the instrument to change to 50% of the step change is usually expressed as τ 0.5. When the step response stability time of the temperature transmitter does not exceed one fifth of the thermocouple (resistance) thermal response stability time τ 0.5, the thermocouple (resistance) thermal response time is used as the thermal response time of the instrument;When the step response stability time of the temperature transmitter does not exceed half of the thermocouple (resistance) thermal response stability time τ 0.5, the thermal response time of the temperature transmitter is used as the thermal response time of the instrument.

Basic error: the basic error of the instrument shall not exceed the composite error of the basic error of thermocouple (resistance) and temperature transmitter.

■ Integrated thermocouple with built-in temperature transmitter measurement range and temperature difference