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
ANSI Thermocouple Type Temp Range (°C) Temp Range (°F) Standard Limits of Error (°C)* Special Limits of Error (°C)
J 0 to 760 32 to 1400 ±2.2 or ±0.75% ±2.2 or ±0.75%
T 0 to 370 32 to 700 ±1 or ±0.75% ±0.5 or ±0.4%
K 0 to 1260 32 to 2300 ±2.2 or ±0.75% ±1.1 or ±0.4%
E 0 to 870 32 to 1600 ±1.7 or ±0.5% ±1 or ±0.4%
S 0 to 1480 32 to 2700 ±1.5 or ±0.25% ±0.6 or ±0.1%
R 0 to 1480 32 to 2700 ±1.5 or ±0.25% ±0.6 or ±0.1%
N 0 to 1246 32 to 2300 ±2.2 or ±0.75% ±1.1 or ±0.4%
B 870 to 1700 1600 to 3100 ±0.5% ±0.25%
TA -200 to 0 -328 to 32 ±1 or ±1.5% B
EA -200 to 0 -328 t0 32 ±1.7 or ±1% B
KA -200 to 0 -328 tp 32 ±2.2 or ±2% B

A: Thermocouple and thermocouple materials are normally supplied to meet the tolerances specified in the table of temperatures above 0°C. The same materials, however, may not fall within the tolerances given for temperatures below 0°C in the normal section in the table. If materials are required to meet the tolerances stated for temperatures below 0°C the purchase order must state so. Selection of materials will usually be required.

B: Special tolerances for temperatures below 0°C are difficult to justify due to limited available information.

*: Standard and special limits of error in °F are 1.8 times larger thant the °C tolerance at the equivalent °C temperature.

WIRE INSULATION MATERIAL


POLYVINYL CHLORIDE INSULATED WIRE

Polyvinyl Chloride-Polyvinyl Chloride - PP

Color-coded polyvinyl chloride is extruded on each individual conductor and on the outer jacket. It has dielectric and mechanical strength, plus flexibility. PVC is resistant to flame, moisture and abrasion. It is also inexpensive and easily pulled through a conduit. lt is offered in thermocouple extension grade. Temperature rating: Continuous: -20 to +221°F (-29 to 105°C)

Polyvinyl Chloride Rip-Cord Construction - PC

Polyvinyl chloride is extruded on both positive and negative conductors simultaneously to form a rip-cord construction. Offered in thermocouple grade 24 gauge solid conductors. Temperature rating: Continuous: -20 to +221°F (-29 to 105°C)

Polyvinyl Chloride with Twisted Conductors, Aluminum Mylar* Shield, and Drain Wire - PA

Polyvinyl chloride insulates the positive and negative conductors. The conductors are then twisted and helically wrapped with an aluminum backed Mylar* tape. A bare copper drain wire runs through the construction in contact with the aluminum tape furnishing a low resistance path to ground. The twisted shield provides electrostatic interference rejection. The outer jacket is of polyvinyl chloride which has excellent mechanical strength. Wire is resistant to flame, moisture, and abrasion. Offered in extension grade. Thermocouple grade available upon request. Temperature rating: Continuous: Up to 176°F and 80°C

*Trade name of DuPont.

KAPTON INSULATED WIRE

Kapton - KK

Kapton polyimide film is applied to both the positive and negative conductor or just to the positive conductor. Kapton is highly resistive to abrasion, radiation and is non-flammable. Excellent for use in extremely harsh environments. No ISA/ ASTM color code. Kapton has no known organic solvents. Kapton is an excellent choice for cryogenic environments because its insulating characteristics remain intact at lower temperatures. Offered in thermocouple grade. Temperature rating: Continuous: Up to 550°F (285°C). Intermittent: Up to 750°F (400°C).

NYLON INSULATED WIRE

Nylon-Nylon - NN

Color-coded nylon is extruded on both positive and negative conductors with a nylon outer jacket. This insulation has excellent abrasion resistance, excellent chemical resistance, and poor moisture resistance. Offered in thermocouple grade. Temperature rating: Continuous: Up to 350°F and 177°C.

TEFLON INSULATED WIRE

Teflon (extruded) Teflon (extruded) - TT

Color-coded Teflon (FEP)* is extruded on the positive and negative conductors and outer jacket. This insulation is unaffected by most corrosive substances, outdoor weather, or lubricants. It is flame resistant and heat aging will not cause embrittlement or cracking. Good for cryogenic applications. Offered in thermocouple grade. Temperature rating: Continuous: Up to 400°F (200°C).

Teflon (Fused TFE Tape) Teflon (Fused TFE Tape) - TF

TFE tape is spirally applied to the conductor and heated. This process fuses the tape into a homogeneous layer of TFE. Fused teflon wire offers good abrasion resistance and excellent resistance to both moisture and chemicals. Offered in thermocouple grade. Temperature rating: Continuous: Up to 500°F (260°C).

*DuPont Trademark

FIBROUS INSULATED WIRE

Fiberglass Braid - GG

Glass braid on individual conductors with glass braid outer jacket. Designed for continuous use in high temperature applications. Poor abrasion and moisture resistance. Offered in thermocouple grade. Temperature rating: Continuous: Up to 900°F (482°C). Intermittent: Up to 1000°F (529°C).

Hightemp Fiberglass Braid - HG

A high temperature fiberglass braid is applied over each conductor and then impregnated with a binder. Although the binder improves resistance to abrasion and moisture, it is destroyed above 400°F (204°C). Offered in thermocouple grade. Temperature rating: Continuous: Up to 1300°F (705°C). Intermittent: Up to 1600°F (871°C). We recommend SS overbraid with this wire (Ordering Code HS).

Fiberglass and Hightemp Fiberglass Braid with Stainless Steel Overbraid - GS and HS

A stainless steel overbraid is applied to fiberglass (Ordering Code GS) or high temperature fiberglass (Ordering Code HS) wire insulation to increase the wire’s resistance to abrasion, mechanical and physical damage. It may be applied to 14 through 30 gauge conductors. Other overbraid materials such as Inconel* are also available by special order codes.

*Special Metals Corporation Trademark

Refrasil - RR

Vitreous silica is applied on both positive and negative conductors with a vitreous silica outer jacket. Refrasil is typically not color coded. Used in high temperature applications, including furnace, load thermocouple and traveling thermocouple applications. Moisture and abrasion resistance only fair. Offered in thermocouple grade. Available with SAE AMS 2750 compliant calibration data. Temperature rating: Continuous: Up to 1600°F (871°C). Intermittent: Up to 1800°F (982°C). We recommend stainless steel or other overbraid with this wire.

Nextel - NE

A high temperature ceramic fiber is applied over each conductor and then overall. Nextel is not colored coded. Although nextel is not recommended for use with platinum thermocouples, it can be used as an excellent option for other high temperature applications. Its use is limited by the temperature rating of the thermocouple wire it insulates. It is frequently used in furnace and traveling thermocouple applications. Available with SAE AMS 2750 compliant calibration data. Temperature rating: Continuous: Up to 2200°F (1200°C). We recommend SS overbraid with this wire.

ACCURACY OF JMS EXTENSION WIRE

Thermocouple extension wire has approximately the same thermoelectric characteristics as thermocouple wire, but its accuracy is guaranteed over a more limited range of temperatures. Thermocouple extension wire can offer advantages in cost when used for connections between thermocouples and instruments. For base metal types of thermocouples, extension wire is of substantially the same composition as the corresponding thermocouple type. For noble metal types, however, an entirely different alloy is formulated to match the noble metal characteristics over a specified temperature range. This is necessary due to the high cost of the noble metals which would otherwise be necessary for the interconnection. The “X” in the ordering codes denotes extension grade wire.

Fahrenheit

TC Type °F
EXTENSION WIRE ALLOY ANSI TYPE SYMBOL TEMPERATURE RANGE °F STANDARD LIMITS ORDER CODE SPECIAL LIMITS ORDER CODE
Copper vs. Constantan™ TX -75° to +210° ±2° TX ±1° TTX
Iron vs. Constantan™ JX +32 to +400° ±4° JX ±2° JJX
Chromel™ (+) vs. Constantan™ EX +32 to +400° ±3° EX ±2° EEX
Chromel™ vs. Alumel™ KX +32 to +400° ±4° KX ±2° KKX
Nicrosil™ vs. Nisil™ NX +32 to +400° ±4° NX ±2° NNX
Copper vs. Copper Alloy SX +75 to +400° ±12° SX
Copper vs. Copper Alloy RX RX
PCLW630 vs. Copper BX +32 to +400° ±4° BX
Copper vs. Copper 2CU +32 to +150° ±2° BX
Alloy 203 vs. Alloy 225 W3X +32 to +500° ±12° W3X
Alloy 405 vs. Alloy 426 W5X +32 to +1600° ±12° W5X


Celsius

TC Type °C
EXTENSION WIRE ALLOY ANSI TYPE SYMBOL TEMPERATURE RANGE °C STANDARD LIMITS ORDER CODE SPECIAL LIMITS ORDER CODE
Copper vs. Constantan™ TX -60° to +100° ±1° TX ±.5° TTX
Iron vs. Constantan™ JX +0 to +200° ±2.2° JX ±1.1° JJX
Chrome™l (+) vs. Constantan™ EX 0 to +200° ±1.7° EX ±1.1° EEX
Chromel™ vs. Alumel™ KX 0 to +200° ±2.2° KX ±1.1° KKX
Nicrosil™ vs. Nisil™ NX 0 to +200° ±2.2° NX ±1.1° NNX
Copper vs. Copper Alloy SX +25 to +200° ±7° SX
Copper vs. Copper Alloy RX RX
PCLW630 vs. Copper BX 0 to +200° ±2.2° BX
Copper vs. Copper 2CU 0 to 65° ±1° BX
Alloy 203 vs. Alloy 225 W3X 0 to 260° ±7° W3X
Alloy 405 vs. Alloy 426 W5X 0 to 870° ±7° W5X


Special Note: Using Cu/ Cu wire for type B thermocouples can introduce an error from 7°F to 85°F(3.7°C to 48°C) if the connection point is from 212 - 572°F (100 - 300°C). Up to 99% of these errors are avoided by using the appropriate extension wire.

ANSI: TYPE, J - Iron / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
PP161JX 16 Solid .137 Polyvinyl Chloride Polyvinyl Chloride .111 x .188” 27 lbs.
PA161JX 16 Solid .137 PVC/Alum. Mylar Shield (Twisted) PVC .222” 28 lbs.
PA201JX 20 Solid .357 PVC/Alum. Mylar Shield (Twisted) PVC .184” 20 lbs.
PP201JX 20 Solid .357 Polyvinyl Chloride Polyvinyl Chloride .095 x .158” 14 lbs.
PP202JX 20 Stranded .317 Polyvinyl Chloride Polyvinyl Chloride .115 x .190” 14 lbs.
PX201JX 20 Solid .357 (FEP) Extruded Teflon Extruded Teflon .072 x .124” 11 lbs.


ANSI: TYPE, K - Chromel / Alumel
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
PA161KX 16 Solid .233 PVC/Alum. Mylar Shield (Twisted) PVC .222” 28 lbs.
PP161KX 16 Solid .233 Polyvinyl Chloride Polyvinyl Chloride .116 x .188” 27 lbs.
PA201KX 20 Solid .590 PVC/Alum. Mylar Shield (Twisted) PVC .184” 20 lbs.
PP201KX 20 Solid .590 Polyvinyl Chloride Polyvinyl Chloride .195 x .158” 14 lbs.
PP202KX 20 Stranded .538 Polyvinyl Chloride Polyvinyl Chloride .115 x .190” 14 lbs.


ANSI: TYPE, T - Copper / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
PP141TX 14 Solid .074 Polyvinyl Chloride Polyvinyl Chloride .130 x .226” 37 lbs.
PA161TX 16 Solid .118 PVC/Alum. Mylar Shield (Twisted) PVC .222” 20 lbs
PP161TX 16 Solid .118 Polyvinyl Chloride Polyvinyl Chloride .111 x .188” 28 lbs.
PA201TX 20 Solid .298 PVC/Alum. Mylar Shield PVC .184” 20 lbs.
PP201TX 20 Solid .298 Polyvinyl Chloride Polyvinyl Chloride .095 x .158” 15 lbs.


ANSI: TYPE, E - Chromel / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
PA161EX 16 Solid .278 PVC/Alum. Mylar Shield (Twisted) PVC .222” 20 lbs.
PP201EX 20 Solid .704 Polyvinyl Chloride Polyvinyl Chloride .095 x .158” 15 lbs.


ANSI: TYPE, S and R - Platinum / Rhodium
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
PP161SX 16 Solid .016 Polyvinyl Chloride Polyvinyl Chloride .116 x .250” 27 lbs.
GG201SX 20 Solid .040 Glass Braid Glass Braid .059 x .105” 8 lbs.
PP201SX 20 Solid .040 Polyvinyl Chloride Polyvinyl Chloride .095 x .158 14 lbs.


*ohms per double foot at 20°C (68°F).

ANSI: TYPE, J - Iron / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
GG210J 20 Solid .357 Glass Braid Glass Braid .059 x .105” 8 lbs.
GG202J 20 Stranded .317 Double Glass Braid Glass Braid .075 x .137” 9lbs.
KK201J 20 Solid .357 Fused Kapton Tape None, Twisted .087” 10 lbs.
NN201J 20 Solid .357 Nylon Nylon .068 x .120” 11 lbs.
TF201J 20 Solid .357 (TFE) tape, Teflon (TFE) tape, Teflon .065 x .110” 10 lbs.
TX201J 20 Solid .357 Extruded (FEP) Teflon Extruded (FEP) Teflon .072 x .124” 11 lbs.
GG241J 24 Solid .877 Glass Braid Glass Braid .047 x .081” 4 lbs.
KK241J 24 Solid .877 Fused Kapton Tape None, Twisted .063” 5 lbs.
PP241J 24 Solid .877 Polyvinyl Chloride None, Rip-Cord .048 x .096” 4 lbs.
TF241J 24 Solid .877 (TFE) tape, Teflon (TFE) tape, Teflon .047 x .078” 5 lbs.
GG261J 26 Solid 1.394 Glass Wrap Glass Braid .040 x .065” 3 lbs.
GG281J 28 Solid 2.216 Glass Wrap Glass Braid .037 x .059” 3 lbs.
GG301J 30 Solid 3.520 Glass Wrap (Braid avail.) Glass Braid .033 x .053” 3 lbs.


ANSI: TYPE, K - Chromel / Alumel
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
GG201K 20 Solid .590 Glass Braid Glass Braid .059 x .105” 8 lbs.
GG202K 20 Stranded .538 Double Glass Braid Glass Braid .075 x .137” 9 lbs.
KK201K 20 Solid .590 Fused Kapton Tape None, Twisted .087” 10 lbs.
RR201K 20 Solid .590 Vitreous Silica Braid Vitreous Silica Braid .102 x .174” 16 lbs.
TF201K 20 Solid .590 (TFE) tape, Teflon (TFE) tape, Teflon .065 x .110” 10 lbs.
TX201K 20 Solid .590 Teflon Extruded (FEP) Teflon Extruded .072 x .124” 11 lbs.
GG241K 24 Solid 1.490 Glass Braid (Wrap avail.) Glass Braid .047 x .081” 4 lbs.
PP241K 24 Solid 1.490 Polyvinyl-Rip Cord Const. None .048 x .096” 4 lbs.
GG261K 26 Solid 2.370 Glass Wrap Glass Braid .040 x .065” 3 lbs.
GG281K 28 Solid 3.770 Glass Braid (Wrap avail.) Glass Braid .039 x .064” 3 lbs.
GG301K 30 Solid 5.980 Glass Wrap Glass Braid .033 x .053” 2 lbs.


ANSI: TYPE, T - Copper / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
GG201T 20 Solid .298 Glass Braid (Wrap avail.) Glass Braid .059 x .105” 5 lbs
TF201T 20 Solid .298 (TFE) tape, Teflon (TFE) tape, Teflon .065 x .110” 10 lbs.
TX201T
GG241T 20 Solid .298 Extruded Teflon (FEP) Extruded Teflon .072 x .124” 11 lbs.
NN241T
PP241T 24 Solid .753 Nylon Nylon .060 x .095” 6 lbs.
TF241T 24 Solid .753 (TFE) tape, Teflon (TFE) tape, Teflon .047 x .078” 5 lbs.
GG281T 28 Solid 1.905 Glass Braid (Wrap avail.) Glass Braid .039 x .064” 3 lbs.
GG301T 30 Solid 3.025 Glass Wrap Glass Braid .033 x .053” 2 lbs.


ANSI: TYPE, E - Chromel / Constantan
Catalog Number Guage Size Conductors *Ohms Primary Insulation Outer Jacket Min-Max. O.D. Est. Shpg. Wt. per M
GG201E 20 Solid .704 Glass Braid Glass Braid .059 x .105” 8 lbs.
GG241E 24 Solid 1.780 Glass Braid Glass Braid .047 x .081” 4 lbs.


*ohms per double foot at 20°C (68°F).