Outline 
 Industrial assembly-type thermocouple as a temperature sensor, usually, and display instruments, recording instruments and supporting the use of electronic regulator. Thermocouple assembly of production can be measured directly from the range 0 ℃ to 1800 ℃ of liquid vapor, gas and solid surface temperature. 
 According to state regulations, the company produced in accordance with IEC international standard indexing of platinum and rhodium, No. 30 - 6 platinum and rhodium, platinum and rhodium 10 - platinum, nickel, chromium - nickel silicon, nickel, chromium - constantan thermocouple assembly and so on. 
 Assembly thermocouple temperature sensing element is usually installed fixtures and junction boxes and other major components. 
 Measuring range and allowable error range 

 Thermocouple type code number indexing the basic error of measurement range limit 
 Nickel-chromium - constantan WRK E 0-800 ℃ ± 0.75% t 
 Nickel-chromium - nickel silicon WRN K 0-1300 ℃ ± 0.75% t 
 Platinum Rhodium 13 - Platinum WRB R 0-1600 ℃ ± 0.25% t 
 Platinum Rhodium 10 - Platinum WRP S 0-1600 ℃ ± 0.25% t 
 Platinum Rhodium 30 - Platinum Rhodium 6 WRR B 0-1800 ℃ ± 0.25% t 
 Note: t is the measured temperature sensing element temperature (℃) 

 Thermocouple time constant level of thermal inertia time constant (seconds) time constant level of thermal inertia (seconds) 
 Ⅰ 
 90-180 Ⅲ 
 10-30 
 Ⅱ 
 30-90 Ⅳ 
 <10 
 Thermocouple pressure: generally refers to the operating temperature protection tube can withstand a static external pressure and rupture. 
 Thermocouple minimum insertion depth: its protective casing should be not less than 8-10 times the diameter of the (special exceptions listed products) 
 Insulation resistance: When the ambient air temperature is 15-35 ℃, relative humidity <80% ≥ 5 megohm insulation resistance (voltage 100V). Junction box with a splash-type thermocouple, when the relative temperature of 93 ± 3 ℃, the insulation resistance of ≥ 0.5 megohm (voltage 100V) 
 Insulation resistance under high temperature: thermocouples at high temperatures, the thermal electrode (including the double-supported) and double support and protection tube heat insulation resistance between the electrodes (per meters) should be greater than the value specified in the table below. Required long-term use temperature (℃) 
 Test temperature (℃) 
 Insulation resistance (Ω) 

 ≥ 600 600 7200 0 
 ≥ 800 800 2500 0 
 ≥ 1000 1000 5000