Type

Single Color

Ansi Color Coding

Overall Extension

Overall Thermocouple

Conductor Alloys

Temperature Range °F (°C)

Thermocouple Grade

Extension Grade

Tolerance(standard)

/ Whichever is Greater

Tolerance(Special)

/ Whichever is Greater

E

Purple

Red

Purple

Brown

EP/EN Chromel/Constantan

-328 to 1652

(-200 to 900)

32 to 392

(0 to 200)

+-1.7 °C

or +-0.5%

+-1.0 °C

or +-0.4%

J

White

Red

Black

Brown

JP/JN Iron/Constantan

32 to 1382

(0 to 750)

32 to 392

(0 to 200)

+-2.2 °C

or +-0.75%

+-1.1 °C

or +-0.4%

K

Yellow

Red

Yellow

Brown

KP/KN Chromel/Alumel

328 to 2282

(-200 to 1250)

32 to 392

(0 to 200)

+-2.2 °C

or +-0.75%

+-2.2 °C

or +-0.75%

N

Orange

Red

Orange

Brown

NP/NN Nicrosil/Nisil

-450 to 2372

(-270 to 1300)

32 to 392

(0 to 200)

+-2.2 °C

or +-0.75%

(2% below 0 °C)

+-2.2 °C

or +-0.75%

(2% below 0 °C)

T

Blue

Red

Blue

Brown

TP/TN Copper/Constantan

-328 to 662

(-270 to 350)

32 to 392

(0 to 200)

+-2.2 °C

or +-0.75%

(1.5% below 0 °C)

+-0.5 °C

or +-0.4%

B

Grey

Red

Grey

None

BP/BN Platinum 30% Rhodium

Platinum 6% Rhodium

32 to 3092

(0 to 1700)

32 to 212

(0 to 100)

+-3.7 °C

or +-0.5% over 800 °C

NOT ESTABLISHED

C

White

Red

White

Red Trace

None

CP/CN Tungsten 5% Rhenium

Tungsten 26% Rhenium

32 to 4208

(0 to 2320)

32 to 1600

(0 to 870)

+-4.5 °C to or 425 °C

1% to 2320 °C

NOT ESTABLISHED

R/S

Black

Red

Green

None

RP/RN R=Platinum/13% Rhodium

S=10% Rhodium/Pure Platinum

32 to 2462

(0 to 1450)

32 to 300

(0 to 150)

1.5 °C or 0.25%

0.6 °C or 0.1%