Thermocouple Wire & Cable
When two wires of dissimilar metals are joined at both ends and one of the ends is heated, a continuous current flows in a thermoelectric circuit. All dissimilar metals exhibit this effect. The most common combinations of two metals are listed in the thermocouple specification table below, and are referred to as thermocouples. Common thermocouple types are: E, J, K, and T. Thermocouple wires are also used in thermocouple cable to manufacture thermocouple probes utilizing either soft insulations like Teflon® or fiberglass or mineral insulated cables with metal sheaths such as stainless steel or nickel alloys.
Common Beneficial Features of Thermocouple Wires and Cables
The common beneficiary features of the thermocouple cables or thermocouple wires are detailed as follows:
- Thermocouple wires are available in vast temperature ranges. Depending on the type of wire, insulation, calibration temperature, and the tolerance range varies.
- For example, Type K thermocouple wire offers a range of -328 to 2282° F temperature range, or 32- 392°F for extension wire. Wire is also offered in Standard or Special limits of error as indicated in the table below.
- Thermocouple cables are color-coded according to industrial standards to identify the capabilities of the cable. There are differences in color coding based on International standards.
- Therm-x stocks thermocouple wire in standard AWG from 20-30 AWG
- Standard insulations are Fiberglass, Teflon and PVC
- Stainless steel and other overbraid insulations are available over soft wire for protection against abrasion
Thermocouple Wire Specifications
The below given chart will help you understand different thermocouple wires and their properties better. This information will be of great help in your selection process.
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Thermocouple Wire Specifications | ||||||
T/C 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 deg C or +-0.5% |
+-1.0 deg 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 deg C or +-0.75% |
+-1.1 deg 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 deg C or +-0.75% |
+-1.1 deg C or +-0.4% |
N | Orange Red |
Orange | Brown | NP/NN Nicrosil/Nisil | -450 to 2372 (-270 to 1300) 32 to 392 (0 to 200) |
+-2.2 deg C or +-0.75% (2% below 0 deg C) |
+-1.1 deg C or +-0.4% |
T | Blue Red |
Blue | Brown | TP/TN Copper/Constantan | -328 to 662 (-270 to 350) 32 to 392 (0 to 200) |
+-2.2 deg C or +-0.75% (1.5% below 0 deg C) |
+-0.5 deg 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 deg C or +-0.5% over 800 deg 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 deg C to or 425 deg C 1% to 2320 deg 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 deg C or .25% | .6 deg C or .1% |
Application Areas of Thermocouple Wires and Cables
Thermocouples wires and cables used in applications where thermocouples are used to extend the signal to the controller or readout instrument. Following are the areas of application for our thermocouple wires
- Extension to Thermocouple probes
- Thermocouples for Lab or industrial use
- Wiring to instrumentation accepting thermocouple signals