Thermocouple Color Codes / Conductor Combinations & Characteristics

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Below is a chart of the thermocouple codes/conductor combinations per different countries and their characteristics. Countries listed in this chart include: United States of America, United Kingdom, Germany, Japan, and France.

Thermocouple codes in this chart include: K, V, T, J, E, N, R, S, B, U, W, W₅, and W₃.

Code	Conductor Combinations		Approximate Generated EMF Change per Degree F change with Reference Junction at 0°F µV / °F at...			Approximate Working Temperature Range of Measuring Junction °F		National Standards for Output of Thermocouple Conductors (Those standards noted in this column all conform with each other and are based upon IPTS 1968 & IEC 584.1:1977.)	Notes
	+ leg	- leg	212°F	932°F	1832°F	Continuous	Short Term
K	Nickel-Chromium Also known as: Chromel, Ni-Cr, T1	Nickel-Aluminum Also known as: Ni-Al, Alumel, KN, T2	23.33	23.89	21.67	32 to +2012	-292 to +2462	ANSI/MC96.1 Type "K" BS4937 part 4 DIN 43710 JIS C 1602 NF C 42-321	Wide range and most commonly used. ANSI/MC96.1 Type "K" replaced circular 561.
V	Copper	Copper-Nickel Also known as: Constantan, Nickel	Used for interconnecting Type "K" thermocouples and instrumentation as an alternative to Type "K" material. Only used where the interconnection temperature is in the range of 32°F to +176°F						Color coded for use as a compensating cable for Type "K" thermocouples. This compensating cable can also be used for extending Type "T" thermocouples.
T	Copper	Copper-Nickel Also known as: Nickel, Cupron, Constantan	25.55			-301 to +572	-328 to +662	ANSI/MC96.1 Type "T" BS4937 part 5 JIS C 1602 NF-C 42-321	Many low temperature and cryogenic applications. Suitable for use in a mildly oxidizing or reducing atmosphere as an unprotected thermocouple sensor. ANSI/MC96.1 Type "T" thermocouple replaced circular 561.
J	Iron (magnetic) Also known as: FE	Copper-Nickel Also known as: Constantan, Cupron	25.55	31.11	32.78	+68 to +1292	-292 to +1382	ANSI/MC96.1 Type "J" BS4937 part 3 JIS C 1602 NF C 4-321	Commonly used in the plastic molding industry. Used in reducing atmospheres as an unprotected thermocouple sensor. NB Iron rusts at low and oxidizes at high temps. ANSI/MC96.1 Type "J" replaced circular 561.
E	Nickel-Chromium Also known as: Chromel, Chromium Nickel	Copper-Nickel Also known as: Nickel Copper, Constantan	37.78	45.00		32 to +1472		ANSI/MC96.1 Type "E" BS4937 part 6 DIN 43710 JIS C 1602 NF C 42-321	Highest thermal EMF output change/°F. Suitable for use in a vacuum or mildly oxidizing or reducing atmosphere as an unprotected sensor. ANSI/MC96.1 Type "E" replaced circular 561.
N	Nickel-Chromium Silicon Also known as: Nicrosil	Nickel-Silicon-Magnesium Also known as: Nisil	16.67	21.11	21.67	32 to +2012	-450 to +2372		This combination shows good promise as an alternative to Type "K". Appears to be more stable and longer-lived.
R	Platinum- 13% Rhodium	Platinum	4.45	5.56	7.23	32 to +1600	-58 to +3092	ANSI/MC96.1 Type "R" BS4937 part 2 DIN 43710 JIS C 1602 NF C 42-321	Used for high temp applications. Has high resistance to oxidation and corrosion. Easily contaminated and normally requires protection. ANSI/MC96.1 Type "R" replaced circular 561.
S	Platinum- 10% Rhodium	Platinum	4.45	5.00	6.11	32 to +2822	-58 to +3092	ANSI/MC96.1 Type "S" BS4937 type 1 DIN 43710 JIS C 1602 NF C 42-321	See Type "R". ANSI/MC96.1 Type "S" replaced circular 561.
B	Platinum- 30% Rhodium	Platinum- 6% Rhodium	0.56	2.78	5.00	+212 to +2912	+122 to +3182	ANSI/MC96.1 Type "B" BS4937 part 7 DIN IEC B8 JIS C 1602 NF C 42-321	See Type "R". Commonly used in glass industry. Copper vs copper compensating cable can be used to normal ambient interconnection temps up to 100°C. ANSI/MC96.1 Type "B" replaced circular 561.
U	Copper	Copper-Low Value Nickel Also known as: Nickel	Used for interconnecting Type "R" and "S" thermocouples and instrumentation. Only used where the interconnection temperature is in the range of 32°F to +122°F.						This is a compensating cable only and is used with Types "R" and "S" measuring thermocouple sensors.
W	Tungsten	Tungsten- 26% Rhenium	2.78	8.89	11.67	+68 to +4172	32 to +4712		Tungsten Rhenium alloy combinations offer reasonably high and relatively linear EMF outputs for high temp measurement up to 4712°F and good chemical stability at high temps in hydrogen, inert gas, and vacuum atmospheres. They are not really practicable for use below 752°F. Not recommended for use in oxidizing conditions. Suggested compensating cables are listed below.
W₅	Tungsten- 5% Rhenium	Tungsten- 26% Rhenium	8.34	10.00	10.00	+68 to +4172	32 to +4712
W₃	Tungsten- 3% Rhenium	Tungsten- 25% Rhenium	7.23	11.11	11.11	+68 to +3632	32 to +3812