Answer / rajkumar

Thermocouple
Type Useful/General
Application Range Notes
B 1370-1700°C
(2500-3100°F) Easily contaminated, require protection.
C* 1650-2315°C
(3000-4200°F) No oxidation resistance. Vacuum, hydrogen or
inert atmospheres.
E** 95-900°C
(200-1650°F) Highest output of base metal thermocouples.
Not subject to corrosion at cryogenic temperatures.
J 95-760°C
(200-1400°F) Reducing atmosphere recommended. Iron leg
subject to oxidation at elevated temperatures--use larger
gauge to compensate.
K** 95-1260°C
(200-2300°F) Well suited for oxidizing atmospheres.
N 650-1260°C
(1200-2300°F) For general use, better resistance to
oxidation and sulfur than Type K.
R 870-1450°C
(1600-2640°F) Oxidizing atmosphere recommended. Easily
contaminated, require protection.
S 980-1450°C
(1800-2640°F) Laboratory standard, highly reproducible.
Easily contaminated, require protection.
T** -200-350°C
(-330-660°F) Most stable at cryogenic temperatures ranges.
Excellent in oxidizing and reducing atmospheres within
temperature range.


RTD Resistance Wire Comparisons
Element Metal Temperature Range Benefits Base
Resistance TCR (Ω/Ω/°C)
Platinum -260 to 850°C
(-436 to 1562°F) Best stability, good linearity 100 Ω at
0°C 0.00385 (DIN-IEC-761), 0.003916 (JIS 1604-1981)
Copper -100 to 260°C
(-148 to 500°F) Best linearity 10 Ω at 25°C 0.00427
Nickel -100 to 260°C
(-148 to 500°F) Low cost, High Sensitivity 120 Ω at 0° C
0.00672

Answer / ulaganathan

generall for the measurement of low temperature
range is by using thermistor
and for higher order terms i.e>1300 c we are in
use of thermocouple
greater than that temperature we are in use of
pyrometers

Answer / prashanth

hello Mr.Rajkumar thanks alot for ur reply but the text
alignment seems to be very confusing so if u could just
paste the link for that ans over here it would be very useful.
thanks again :)

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