Overview
Industrial thermocouple assembly as a temperature sensor, usually, and display instruments, recording instruments and supporting the use of electronic regulator. Thermocouple assembly can be directly measured from a variety of production range of 0 ¡æ to 1800 ¡æ of liquid vapor, gas and solid surface temperature¡£
According to state regulations, the production company dividing line with international standards IEC platinum and rhodium No. 30 - 6 platinum and rhodium, platinum and rhodium 10 - platinum, nickel, chromium - nickel silicon, nickel, chromium - constantan thermocouple assembly, etc.¡£
Assembly thermocouple temperature sensing element is usually to install fixtures and junction boxes and other major parts¡£
Measuring range and allowable error range
Thermocouple types |
Code |
Dividing number |
Measuring range |
Basic error limit |
Nickel chrome£Constantan |
WRK |
E |
0£800¡æ |
¡À0.75%t |
Nickel chrome£Ni Si |
WRN |
K |
0£1300¡æ |
¡À0.75%t |
Platinum and rhodium 13 -Platinum |
WRB |
R |
0-1600¡æ |
¡À0.25%t |
Platinum and rhodium 10 £Platinum |
WRP |
S |
0£1600¡æ |
¡À0.25%t |
Platinum and rhodium 30 £Platinum and rhodium 6 |
WRR |
B |
0£1800¡æ |
¡À0.25%t |
Note: t is the measured temperature sensing element temperature (¡æ£©
Thermocouple time constant
Level of thermal inertia |
Time constant (seconds£© |
Time constant |
Time constant (seconds£© |
¢ñ |
90£180 |
¢ó |
10£30 |
¢ò |
30£90 |
¢ô |
£¼10 |
Thermocouple Pressure: generally refers to the working temperature protection tube can withstand external pressure and the rupture of the static¡£
Thermocouple minimum insertion depth: the protective casing should be not less than 8-10 times the diameter (special exceptions listed products£©
Insulation resistance: When the ambient air temperature is 15-35 ¡æ, relative humidity "80%, ¡Ý 5 megohms insulation resistance (voltage 100V). Junction box with a splash-type thermocouple, when the relative temperature of 93 ¡À 3 ¡æ, the insulation resistance of ¡Ý 0.5 Mohm (voltage 100V£©
Insulation resistance under high temperature: thermocouples at high temperatures, the hot electrode (including double-vessel type) and the protection tube and double-vessel thermal insulation resistance between the electrodes (per meters) should be greater than the value specified in the following table¡£
Prolonged use of prescribed temperature£¨¡æ£© |
Test temperature£¨¡æ£© |
Insulation resistance£¨¦¸£© |
¡Ý600 |
600 |
72000 |
¡Ý 800 |
800 |
25000 |
¡Ý1000 |
1000 |
5000 |
|