Thermocouple Type | Material | Magnetic | ASTM Color Coding | IEC Color Coding |
---|---|---|---|---|
J | Iron Constantan |
Yes No |
White Red |
White Black |
T | Copper Constantan |
No No |
Blue Red |
White Brown |
K | Chromel Alumel |
No No |
Yellow Red |
White Green |
E | Chromel/Constantan | No No |
Purple Red |
White Violet |
P | Platinel | N/A | N/A | N/A |
S | Platinum 10% Rhodium Pure Platinum |
No No |
Black Red |
White Orange |
R | Platinum 13% Rhodium Pure Platinum |
No No |
Black Red |
white Orange |
B | Platinum 30% Rhodium Platinum 6% Rhodium |
No No |
Grey Red |
White Grey |
N | Nicrosil/Nisil | No Slightly |
Orange Red |
White Pink |
C | Tungsten 5% Rhenium/ Tungsten 26% Rhenium | No No |
White Red |
N/A |
Organization | Standard | Alpha | Nominal Resistance(ohms) At 0°C |
---|---|---|---|
American Scientific Apparatus Makers Association (SAMA) |
RC21-4-1966 | 0.003923 | 98.129 |
British Standards Association |
b.S. 1904-1964 | 0.003850 | 100 |
Normenstelle Elektrotechnik |
DIN 43760 | 0.003850 | 100 |
International Electrotechnical Commission (Supersedes BS&DIN) |
IEC 751: 1983 | 0.003850 | 100 |
US Department of Defense |
MIL-T-24388 | 0.00392 | 100 |
Material Symbol |
Sheath Material |
Melting Point(°F) |
Max Temp; In Air(°F) |
Atmosphere* |
---|---|---|---|---|
H | 304 SS | 2550 | 1650 | ORNV |
J | 310 SS | 2550 | 2100 | ORNV |
L | 316L SS | 2550 | 1650 | ORNV |
O | 446 SS | 2700 | 2100 | ORNV |
M | Inconel 600 | 2500 | 2100 | ONV |
P | Inconel 702 | 2620 | 1500 | ONV |
Q | Platinum | 3216 | 3000 | ON |
R | Molybdenum | 4750 | 1000 | VNR |
T | Titanium | 3300 | 600 | V |
V | STABALOY | 2552 | 2220 | ORNV |
*KEY
O=Oxidizing, R=Reducing, N=Neutral, V=Vacuum
Suggested Upper Limit for Outside Diameter (Single Element) °C (°F) | ||||||
---|---|---|---|---|---|---|
Sheath | Thermocouple Type | |||||
In | mm | T | J | E | K | N |
1/25" | 1.0 | 260° (500°) | 260° (500°) | 300° (570°) | 700° (1290°) | 2700° (1290°) |
1/16" | 1.6 | 260° (500°) | 440° (825°) | 510° (950°) | 920° (1690°) | 920° (1690°) |
1/8" | 3.2 | 315° (600°) | 520° (970°) | 650° (1200°) | 1070° (1950°) | 1070° (1950°) |
3/16" | 4.8 | 370° (700°) | 620° (1150°) | 730° (1350°) | 1150° (2100°) | 1150° (2100°) |
1/4" | 6.3 | 370° (700°) | 720° (1330°) | 820° (1510°) | 1150° (2100°) | 1150° (2100°) |
3/8" | 9.5 | 370° (700°) | 720° (1330°) | 820° (1510°) | 1150° (2100°) | 1150° (2100°) |