Thermocouple

A thermocouple is an electrical device consisting of two dissimilar electrical conductors forming electrical junctions at differing temperatures. A thermocouple produces a temperature-dependent voltage as a result of the thermoelectric effect, and this voltage can be interpreted to measure temperature. Thermocouples are a widely used type of temperature sensor.

Common Temperature Probes style


Industral Head	Transition Joint Probes	Handheld

熱電偶之材質

Type		Range	Comments
B	+ 70%Platinum+30%Rhodium	0~1700°C	Oxidizing or Inert; High Temperature.
B	- 94%Platinum+6%Rhodium	0~1700°C	Oxidizing or Inert; High Temperature.
R	+ 87%Platinum+13%Rhodium	0~1450°C	Oxidizing or Inert; High Temperature.
R	- Platinum	0~1450°C	Oxidizing or Inert; High Temperature.
S	+ 90%Platinum+10%Rhodium	0~1450°C	Oxidizing or Inert; High Temperature.
S	- Platinum	0~1450°C	Oxidizing or Inert; High Temperature.
K	+ Nickel- Chromium	-200~1250°C	Clean Oxdizing and Inert; Wide Temperature Range; Most popular.
K	- Nickel- Aluminum	-200~1250°C
N	+ Nickel +14.2% Chromium +1.4% Silicon	-270~1300°C	Alternative to Type K; More Stable at High Temperature.
N	- Nickel +Silicon 4.4%+ Magnesium 0.1%	-270~1300°C	Alternative to Type K; More Stable at High Temperature.
E	+ Nickel-Chromium	-200~900°C	Oxidizing or Inert; Highest EMF Change per Degree.
E	- Copper-Nickel	-200~900°C	Oxidizing or Inert; Highest EMF Change per Degree.
J	+ Iron	0~750°C	Reducing, Vacuum, Inert; Not Recommended for Low Temperatures.
J	- Copper-Nickel	0~750°C
T	+ Copper	-200~350°C	Mild Oxidzing, Reducing, Vacuum or Inert; Good Where Moisture Is Present; Low Temperature and Cryogenic Applications.
T	- Copper-Nickel	-200~350°C

熱電偶起電力表

Accuracy

1.ASTM E230-1998, E988-1996

Type	Temperature Range	Tolerance Grades
Type	Temperature Range	Standard	Special
B	Above 870°C Below 1700°C	0.5%	-
R·S	Above 0°C Below1450°C	±1.5°C or ±0.25%	±0.6°C or ±0.10%
K	-200°C Below0°C	±2.2°C or ±2.00%
K	Above 0°C Below1250°C	±2.2°C or ±0.75%	±1.1°C or ±0.40%
N	Above -270°C Below0°C	±2.2°C or ±2.00%
N	Above 0°C Below1300°C	±2.2°C or ±0.75%	±1.1°C or ±0.40%
E	Above -200°C Below0°C	±1.7°C or ±1.00%
E	Above 0°C Below900°C	±1.7°C or ±0.50%	±1.0°C or ±0.40%
J	Above 0°C Below750°C	±2.2°C or ±0.75%	±1.1°C or ±0.40%
T	Above -200°C Below0°C	±1.0°C or ±1.50%
T	Above 0°C Below350°C	±1.0°C or ±0.75%	±0.5°C or ±0.40%

2.JIS C1602-1995 IEC 584-2-1982 (Amendment 1-1989) BS/EN 60584-2-1993 DIN/IEC 584-2-1992

Type	Tolerance Grades
Type	Class 1	Class 2	Class 3
B	－－	－－	Above 600C Below800°C ±4°C
B	－－	Above 600°C Below 1700°C ±0.25%·∣t∣	Above 800°C Below 1700°C ±.5%·∣t∣
R·S	Above 0°C Below 1100°C ±1°C	Above 0°C Below 600°C ±1.5°C	－－
R·S	1100°C Below 1600°C ±[1+0.3%·(t-1100)]°C	Above 600°C Below 1600°C ±0.25%·∣t∣	－－
N	Above -40°C Below375°C ±1.5°C	Above -40°C Below 333°C ±2.5°C	Above -167°C Below 40°C ±2.5°C
N	375°C Below1000°C ±0.4%·∣t∣	Above 333°C Below 1200°C ±0.75%·∣t∣	Above -200°C Below-167°C ±1.5%·∣t∣
K	Above -40°C Below 375°C ±1.5°C	Above -40°C Below 333°C ±2.5°C	Above -167°C Below 40°C ±2.5°C
K	Above 375°C Below1000°C ±0.4%·∣t∣	Above 333°C Below1200°C ±0.75%·∣t∣	Above -200°C Below- 167°C ±1.5%·∣t∣
E	Above -40°C Below375°C ±1.5°C	Above -40°C Below 333°C ±2.5°C	Above -167°C Below 40°C ±2.5°C
E	Above 375°C Below 800°C ±0.4%·∣t∣	Above 333°C Below900°C ±0.75%·∣t∣	Above -200°C Below -167°C ±1.5%·∣t∣
J	Above -40°C Below 375°C ±1.5°C	Above -40°C Below333°C ±2.5°C	－－
J	Above 375°C Below 750°C ±0.4%·∣t∣	Above 333°C Below 750°C ±0.75%·∣t∣	－－
T	Above -40°C Below125°C ±0.5°C	Above -40°C Below133°C ±1°C	Above -67°C Below 40°C ±1°C
T	Above 125°C Below 350°C ±0.4%·∣t∣	Above 133°C Below 350°C ±0.75%·∣t∣	Above -200°C Below -67°C ±1.5%·∣t∣