Technical information

Application of thermocouples
WIKA data sheet IN 00.23

In industrial electrical temperature measurement, two groupsof sensors are commonly used:■■ Resistance temperature detectors (RTD)■■ Thermocouples (TC)
Both sensor types have their advantages and disadvantages.
The commonly used Pt100 RTDs are especially suitedfor measurements in the lower to middle temperature
range (-200 ... +600 °C). Thermocouples, however, (apartfrom a few exceptions) have their advantages at higher
temperatures (up to 1700 °C).
Some thermocouples can measure even higher temperatures(tungsten-rhenium, gold-platinum or platinum-palladium).
These very specific thermocouples are not described in thisdocument.
While in Europe Pt100 sensors are primarily used formeasuring low and medium temperatures, in North America
a clear predominated use of thermocouples can beobserved. However, this does not always apply, e.g a refinery
built in Europe is equipped with temperature measurement
technology which is based on North American standards if
the plant has been designed in the USA. This can also apply
to the other direction.
Another criterion for selecting a thermocouple is the smallest
diameter possible of a sheathed thermocouple (see chapter“Sheathed thermocouples”). The diameters of 0.25 mm,
0.5 mm or 1 mm allow in astonishingly short response times.
In general, thermocouples react faster than RTD's.

Straight thermocouple assembly with metal protection
tube

Cable thermocouple, model TC40
(Design: Sheathed measuring cable (MI cable))

If the thermometer is built into a (massive) thermowell, theresponse times of the two sensor groups approach. Whentaking into account the mass of an assembled thermowell,its heat conduction and the insulation between medium
and sensor relativise in this case the speed advantage ofthe thermocouple. Although it is still measurable, but often
irrelevant as the response time in this case can be in the
doubledigit minute range.

Samples of thermowells

WIKA data sheet IN 00.23 ∙ 09/2016

Page 1 of 13

Basics
Every metal has a material-specific electronegativity.
(Electronegativity = tendency of atoms rather to accept orrelease electrons)

A thermocouple consists of two conductors of dissimilar
metals connected together at one end, whereby theconnection node is the measuring point.
Thermocouple/measuring point

Ceramic insulation
Thermocouple conductors

Following standards define thermocouples
IEC 60584-1: Thermocouples: basic and tolerance values of
the thermoelectric voltages
IEC 60584-3: Thermocouples: Thermocouple cables andcompensating cables

When the measuring point is heated, the voltage on thewire ends (cold junction) is measured; it represents thetemperature of the measuring point.
(Thermoelectric effect = Seebeck effect)
Metal A

T1
Measuring
point

Cold
junction
Metal BTo achieve the highest possible thermoelectric voltages,
special material pairings whose individual electronegativities
are as far apart as possible are used to form thermocouples.
These material pairings have certain limitations - forexample due to the maximum operating temperature of thethermocouple.

ASTM E230:
Standard specification and temperature-electromotive force(EMF) tables for standardised thermocouples.

T2

This voltage (EMF = electromotive force) is produced due
to different electron density of the two (dissimilar) metal
conductors of the wires used - in combination with thetemperature difference between measuring point and cold
junction.
Simply, a thermocouple measures not the absolutetemperature, but the differential temperature between the■■ T1: Measuring point (hot junction)and■■ T2: Cold point (cold junction)

Since the voltage is often measured at ambient temperature,
the displayed voltage value would be too low by the value ofthe voltage of the ambient temperature. To obtain the value
for the absolute measuring point temperature, the so-called“cold junction compensation” is used.
In the past (in calibration laboratories still today), it wasachieved by means of immersing the joint of the cold end of
the thermocouple and the wires of the voltage meter into an
ice bath.
In current instruments with thermocouple input (transmitters,
portable measuring instruments or panel mounted devices,etc.), an electronic cold junction compensation is included in
the circuitry of the instrument.

Page 2 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

Thermoelectric voltages
Reference temperature: 0 °C
Temperature
in °C

-200

Thermocouple
Type K

Type J

Type N

Type E-3.379-100-2.788

-80

20

40

60

80

100

150

200

250

300

350

370

400

-1.527-0.777

0.000

0.798

1.612

2.436

3.267

4.096

6.138

8.138

10.15312.20914.29315.13316.397-1.961-0.995

0.000

1.019

2.059

3.116

4.187

5.269

8.010

10.77913.55516.32719.09020.19421.848-2.255-1.475

0.000

0.000

0.000

0.000

0.000

1.065

2.420

1.612

0.235

0.232

2.189

4.985

3.358

0.502

0.501

4.302

9.789

6.704

1.029

1.041

7.597

17.18112.013

1.874

1.923

11.13624.96417.819

2.786

2.896

12.97428.946

3.259

3.408

16.74837.005

4.233

4.471

-0.518

0.525

1.619

2.774

5.913

9.341

11.86718.51624.61014.846550

22.77630.21618.672

600
650
700
750
760
800
850
870
900
950

1000
1050
1100
1150
1200
1250
1260
1300

20.64424.90527.02529.12931.21331.62833.27527.39333.10236.07139.13242.28142.91935.31336.12137.32639.31441.27643.21145.11946.99548.83850.64451.000

1350
1400
1450
1480
1500
1550

-2.153-1.023450500Type B-3.923-120-20Type R-4.419-1400Type S

-4.865-160-40-5.603-5.261-180-60Type T

20.61322.56624.52726.49126.88328.45530.41631.19932.37134.31936.25638.17940.08741.97643.84645.69446.060-1.152

1.192

3.685

6.319

13.42121.03626.55232.96541.05345.09349.11653.11257.08057.97061.01764.92266.47368.787-0.757

0.790

2.467

4.279

9.288

14.86219.030

0.113

0.365

0.646

1.441

2.323

2.974

3.742
4.732
5.239
5.753
6.275
6.806
6.913
7.345
7.893
8.114
8.449
9.014
9.587

10.16810.757
11.35111.951
12.55412.67513.15913.76614.37314.97815.341
15.582
16.182

0.111

0.363

0.647

1.469

2.401

3.099

3.933
5.021
5.583

1.792

6.743

2.431

6.041
7.340
7.461
7.950
8.571
8.823
9.205
9.850

10.506
11.17311.85012.53513.22813.92614.06614.62915.33416.04016.74617.16917.45118.152

2.101
2.782
2.854
3.154
3.546
3.708
3.957
4.387
4.834
5.299
5.780
6.276
6.786
7.311
7.417
7.848
8.397
8.956
9.524
9.868

10.09910.679Continued on next page
WIKA data sheet IN 00.23 ∙ 09/2016

Page 3 of 13

Temperature
in °C

1600

Thermocouple
Type K

Type J

Type N

Type E

1650
1700

Type T

Type S
16.777

Type R
18.849Type B
11.26311.85012.430Legend:Black: IEC 60584-1 and ASTM E230
Blue: IEC 60584-1 only
Red: ASTM E230 only

Thermoelectric voltage curves

Voltage■■ IEC 60584-1

Voltage■■ ASTM E230

The charts illustrate the curves corresponding to the relevanttemperature ranges of IEC 60584-1 / ASTM E230. Outsidethese temperature ranges, the permissible tolerance value is
not standardised.
Page 4 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

Operating limits and accuracies of thermocouples(IEC 60584, ASTM E230)
The following table contains permissible tolerance values of IEC 60584-1 incl. the tolerance values of ASTM E230 standard
which is common in North America:
Tolerance values of the thermocouples per IEC 60584-1 / ASTM E230 (Reference temperature 0 °C)
Type
K
N

Thermocouple

NiCr-NiAl (NiCr-Ni)
NiCrSi-NiSi

Tolerance value

IEC 60584-1

Class

Temperature range-40 ... +1000 °C±1.5 °C or 0.0040 ∙ | t | 1) 2)

2-40 ... +1200 °C±2.5 °C or 0.0075 ∙ | t |1

0 ... +1260 °C

ASTM E230

Special

IEC 60584-1

1-40 ... +750 °C±1.5 °C or 0.0040 ∙ | t |2-40 ... +750 °C±2.5 °C or 0.0075 ∙ | t |Standard
J

Fe-CuNi

0 ... +1260 °C

0 ... +760 °C

NiCr-CuNi

Cu-CuNi

IEC 60584-1

1-40 ... +800 °C±1.5 °C or 0.0040 ∙ | t |2-40 ... +900 °C±2.5 °C or 0.0075 ∙ | t |IEC 60584-1

ASTM E230

Pt13%Rh-Pt
Pt10%Rh-Pt

IEC 60584-1

0 ... +760 °C

Pt30%Rh-Pt6%Rh±2.2 °C or ±0.75 %0 ... +870 °C±1.0 °C or ±0.4 %Standard

0 ... +870 °C±1.7 °C or ±0.5 %1-40 ... +350 °C±0.5 °C or 0.0040 ∙ | t |2-40 ... +350 °C±1.0 °C or 0.0075 ∙ | t |3-200 ...

±1.0 °C or 0.015 ∙ | t |Special+40 °C

0 ... +370 °C-200 …

±0.5 °C or ±0.4 %0 °C±1.0 °C or ±1.5 %Standard

0 ... +370 °C±1.0 °C or ±0.75 %1

0 ... +1600 °C±1.0 °C or ±[1 + 0.003 (t - 1100)] °C

2

0 ... +1600 °C±1.5 °C or ±0.0025 ∙ | t |ASTM E230

Special0 ... +1480 °C±0.6 °C or ±0.1 %IEC 60584-1

2+600 ... +1700 °C±0.0025 ∙ | t |3+600 ... +1700 °C±4.0 °C or ±0.005 ∙ | t |Special--Standard+870 ... +1700 °C±0.5 %

Standard
B±1.1 °C or ±0.4 %SpecialStandard
RS±2.2 °C or ±0.75 %SpecialASTM E230
T±1.1 °C or ±0.4 %ASTM E230

Standard
E

Tolerance value

ASTM E230

0 ... +1480 °C±1.5 °C or ±0.25 %1) ItI is the value of the temperature in °C without consideration of the sign2) The greater value applies

There are different notations of type K thermocouples in Europe and North America:
Europe:NiCr-NiAl or NiCr-Ni
North America: Ni-Cr / Ni-Al
There is no physical difference, it is just the naming caused by historical reasons.

Types R, S and B
Not available as MI-cable version in class 1 per IEC 60584 or “Special” per ASTM E230

WIKA data sheet IN 00.23 ∙ 09/2016

Page 5 of 13

For the tolerance value of thermocouples, a cold junction temperature of 0 °C has beentaken as the basis. When using a compensating cable or thermocouple cable, an additional
measuring deviation must be considered.
1098Tolerance value in °C

7
6
Legend:Type K Class 2
Type K Class 1

5
4
3
2
1
0

0

200

400

600

800

1000

1200

1400

Temperature in °C

Example:Tolerance value of the accuracy classes 1 and 2 of thermocouple type K

Page 6 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

Information on the application of thermocouples■■ Base-metal thermocouples

Type K

+ leg

- leg

NiCr

-

NiAl

Nickel-Chromium-

Nickel-Aluminum (ferromagnetic)

NiCr-NiAl thermocouples are suitable for use in oxidising or
inert gas atmospheres up to 1200 °C (ASTM E230: 1260 °C)
with the largest wire size.
Protect thermocouples from sulphurous atmospheres. Since
they are less susceptible to oxidation than thermocouples
made of other materials, they are mostly used for
applications at temperatures above 550 °C up to the
maximum working pressure of the thermocouple.
Type J

+ leg
Fe

-

CuNi

-

Copper-Nickel

+ leg

- leg

NiCrSi-

NiSi

Nickel-Chromium-Silicon-

Nickel-Silicon

NiCrSi-NiSi thermocouples are suitable for use in oxidisingatmospheres, in inert gas atmospheres or dry reduction
atmospheres up to 1200 °C (ASTM E230: 1260 °C).
They must be protected from sulphurous atmospheres. They
are very accurate at high temperatures. The source voltage(EMF) and the temperature range are almost the same aswith type K. They are used in applications where a longer
service life and greater stability are required.
Type E

+ leg

- leg

NiCr

-

CuNi

Nickel-Chromium-

Copper-Nickel

NiCr-CuNi thermocouples are suitable for use inoxidising or inert gas atmospheres up to 900 °C(ASTM E230: 870 °C) with the largest wire size. Type E
thermocouples, of all the commonly used thermocouples,develop the highest source voltage (EMF) per °C.

WIKA data sheet IN 00.23 ∙ 09/2016

- leg

Cu

-

CuNi

Copper-Copper-Nickel■■ Precious-metal thermocouples- leg

Iron (ferromagnetic)+ leg

Cu-CuNi thermocouples are suitable for temperatures
below 0 °C with an upper temperature limit of 350 °C(ASTM E230: 370 °C) and can be used in oxidising, reducing
or inert gas atmospheres. They do not corrode in moist
atmospheres.

Type S

Fe-CuNi thermocouples are suitable for use in vacuum,in oxidising and reducing atmospheres or inert gas
atmospheres. They are used for temperature measurements
up to 750 °C (ASTM E230: 760 °C) with the largest wire size.
Type N

Type T

+ leg

- leg

Pt10%Rh-

Pt

Platinum-10%Rhodium-

PlatinumType S thermocouples are suitable for continuous use inoxidizing or inert atmospheres at temperatures up to 1600 °C.
Beware of embrittlement due to contamination.
Type R

+ leg

- leg

Pt13%Rh-

Pt

Platinum-13%Rhodium-

PlatinumType R thermocouples are suitable for continuous use inoxidising or inert gas atmospheres at temperatures up to1600 °C. Beware of embrittlement due to contamination.
Type B

+ leg

- leg

Pt30%Rh-

Pt6%RhPlatinum-30%Rhodium-

Platinum-6%Rhodium

Type B thermocouples are suitable for continuous use inoxidising or inert gas atmospheres and for short-term use
in vacuum environments for temperatures up to 1700 °C.
Beware of embrittlement due to contamination.
Type R, S and B thermocouples are commonly installed
in a pure ceramic closed-ended protection tube. If a metal
thermowell or protection tube is used, an inner closed-ended
protection tube is required. Precious metal thermocouples
are susceptible to contamination. It is strongly recommended
to surround these thermocouples with ceramic material.

Page 7 of 13

Recommended upper temperature limit(Continuous operation)■■ Sheathed thermocouples (see also table “Thermoelectric voltages per IEC 60584-1”)

Thermocouple
type

Recommended upper temperature limit in °C

K700With sheath diameter in mm
0.5

260

J

700

N

300

E

260

T

1.0

1.5

700

2.0

920

260

920

440

700

440

920

300

920

510

260

510

260

260

3.0

1070

520

1070

650

315

4.5

1100

620

1100

6.0

8.0

1100

1100

720

720

1100

730

1100

820

350

820

350

350

Sheath material: Inconel 2.4816 (Inconel 600)
Specifications under consideration of optimum laboratory conditions (relating to air without harmful gases).
Other materials are available resulting in different temperature limits.

■■ Straight thermocouple assembly (see also table “Thermoelectric voltages per IEC 60584-1”)

Thermocouple
type

Recommended upper temperature limit in °C
With wire diameter in mm
0.35

0.5

1.0

3.0

400

400

600

700

700

K
J

700

700

N

700

400

E

350

-

1300

1500

B

700

300

1300

1300

R

1000

600

200

1300

S

1000

800

400

200

T

800

-

-

1500

-

-

-

Specifications under consideration of optimum laboratory conditions (relating to air without harmful gases).

■■ Protected thermocouples (see also table “Suggested upper temperature limits for protected thermocouples”

per ASTM E230)

Thermocouple
type
T

J

E

K and NR and S
B

Upper temperature limit for various wire sizes (Awg) in °C

No. 30 gauge
0.25 mm
[0.010 inch]

150

320

370

760

No. 28 gauge
0.33 mm
[0.013 inch]

200

370

430

870

No. 24 gauge
0.51 mm[0.020 inch]

200

370

430

870

1480

No. 20 gauge
0.81 mm[0.032 inch]

260

480

540

980

No. 14 gauge
1.63 mm[0.064 inch]

No. 8 gauge
3.25 mm[0.128 inch]

590

760

370

650

1090

870

1260

1700

Note:
The specified maximum operating temperatures apply to thethermocouple under optimal environmental conditions. The
maximum working temperature of the thermowells is often
well under the temperature of the thermocouple!

Page 8 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

■■ Sheathed thermocouples (see also table “Suggested upper temperature limits for sheathed thermocouples”

per ASTM E608/E608M)

Nominal sheath
diameterUpper temperature limit for various sheath diameters in °C

Thermocouple type

mm

inch

T

J

E

K and N

-

0.032

260

260

300

700

0.5

1.0

1.5

2.0
-

3.0

4.5

6.0

8.0

0.020

0.040

0.062
-

0.093

0.125

0.188

0.250

0.375

260

260

260

260

260

315

370

370

370

260

260

440

440

480

520

620

720

720

300

300

510

510

580

650

730

820

820

700

700

920

920

1000

1070

1150

1150

1150

Note:
The specified maximum operating temperatures apply to thethermocouple under optimal environmental conditions. The
maximum working temperature of the thermowells is often
well under the temperature of the thermocouple!

WIKA data sheet IN 00.23 ∙ 09/2016

Page 9 of 13

Potential measurement uncertainties
Important factors which counteract the long-term
stability of thermocouples
Ageing effects/contamination■■ Oxidation processes in thermocouples which are notappropriately protected (“bare” thermocouple wires) resultin falsifications of the characteristic curves■■ Foreign atoms (poisoning) that diffuse into the original
alloys lead to changes of these original alloys and thus
falsify the characteristic curve.
■■ The influence of hydrogen leads to the embrittlement of
the thermocouples.
“Base-metal” thermocouples are subject to ageing
and thereby change their temperature/thermal voltage
characteristic curve.
“Precious” PtRh-Pt thermocouples of the types R and S show
virtually no ageing up to 1400 °C.
However, they are very sensitive to contamination. Silicon
and phosphorous destroy the Platinum rapidly. In thepresence of Platinum, Silicon can be released from theisolating ceramic parts, even in slightly reducing atmosphere.
The reduction of SiO2 to Si contaminates the Pt-leg of thethermocouple. This leads to errors of 10 °C and more even if
the volume of Silicon is in the range of a few ppm.
Due to a better ratio of the total material volume to thesurface sensitive to poisoning, the long-term stability of the
precious-metal thermocouples increases with increasing
thermocouple wire diameter. This is why the sensors of
the types S, R and B with thermocouple wire diametersØ 0.35 mm or Ø 0.5 mm (0.015" or 0.020") are available. But:
thermocouple wires with Ø 0.5 mm (0.020") have twice thearea of cross section of the wires with Ø 0.35 mm (0.015") –and are thereby also twice as expensive. Nevertheless, it canbe worth it as a considerably longer service life can equalise
the possibly high service costs (downtime of the plant).

protect it from further oxidation of the chromium, cannot be
formed on the surface of the thermocouple.
The thermocouple is permanently destroyed by this process.
The name green rot is derived from the greenish shimmeringcolouration on the breaking point of the wire.
The thermocouple type N (NiCrSi-NiSi) has in this regard anadvantage due to its Silicon content. Here, a protective oxide
layer forms on its surface under the same conditions.
K effect
The NiCr leg of a type K thermocouple has an orderedalignment with respect to the alignment in the crystal lattice
below approx. 400 °C. If the thermocouple is heated further,a transition to a disordered state occurs in the temperature
range between approx. 400 °C and 600 °C. Above 600 °C, anordered crystal lattice is restored.
If these thermocouples cool too quickly (quicker than approx.
100 °C per hour), the undesirable disordered crystal latticeoccurs again during cooling in the range from approx.
600 °C to approx. 400 °C. In the characteristic curve oftype K, however, a consistently ordered alignment state is
assumed and provided with values. This results in a fault of
thermoelectric voltage of up to approx. 0.8 mV (approx. 5 °C)
in this range.
The K effect is reversible and is largely eliminated again byannealing above 700 °C, followed by correspondingly slow
cooling.
Thin sheathed thermocouples are particularly sensitive in thisregard. Cooling in resting air can already lead to deviationsof 1 °C.
In type N thermocouple (NiCrSi-NiSi), it has been possible toreduce this short-range-order effect by alloying both legs with
Silicon.

The Ni leg of the type K thermocouple is often damaged bysulphur that is present in exhaust gases. Thermocouples of
the types J and T age slightly as the pure metal leg oxidises
first.
In general, rising temperatures cause accelerated ageing
effects.
Green rot
If type K thermocouples are used at temperatures fromapprox. 800 °C to 1050 °C, considerable changes of thethermoelectric voltage can occur. The cause of this is achromium depletion or the chrome oxidation in the NiCr leg(+ leg). The precondition for this is a low concentrationof oxygen or steam in the immediate environment of thethermocouple. The nickel leg is not affected by it. The
consequence of this effect is a drift of the measured valuecaused by decreasing thermoelectric voltage. This effectis accelerated if there is a shortage of oxygen (reducing
atmosphere), since a complete oxide layer, which would

Page 10 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

Standard designs of thermocouples
Sheathed thermocouples
Sheathed thermocouples consist of an outer metallic sheath,containing internal leads, which are embedded and isolated
by a highly compressed ceramic compound. (mineralinsulated cable, also called MI cable).
Sheathed thermocouples are bendable and may be bent toa minimum radius of five times the sheath diameter. Due tothis, sheathed thermocouples can also be used in places thatare difficult to access.
The extreme vibration resistance is another good reason forusing sheathed thermocouples.

Straight thermocouple assembly with metal or ceramic
protection tube

Available sheath diameters■■ 0.5 mm■■ 1.0 mm■■ 1.5 mm■■ 3.0 mm■■ 4.5 mm■■ 6.0 mm

Different designs, model TC80■■ Stainless steel 316

Internal design of the thermocouples, straight version
Base-metal thermocouple
types K, N, J

Precious-metal thermocouples
types S, R, B

Ceramic insulators

3168477.01

Sheath materials■■ Ni-alloy 2.4816 (Inconel 600)
- up to 1200 °C (air)- standard material for applications which require specificcorrosion resistance properties under exposure to hightemperatures, resistant to induced stress corrosion
cracking and pitting in media containing chloride- resistant to corrosion caused by aqueous ammonia in all
temperatures and concentrations- highly resistant to halogens, chlorine, hydrogen chloride

3168469.01■■ 8.0 mm

Insulation rod- up to 850 °C (air)- good corrosion resistance with aggressive media as well
as steam and flue gases in chemical media■■ Other materials on request

Design of measuring points
Measuring point insulated(ungrounded)
Thermocouple

Measuringpoint

Measuring point not
insulated (grounded)
Thermocouple

SheathMeasuringpoint

SheathMeasuring point(welded thermocouple)
Precious-metal thermocouples types S, R, B

Thermocouple wire: Ø 0.35 mm or Ø 0.5 mm
Insulation:
Insulation rod, ceramic C 799 / alumina
Base-metal thermocouple types K, N, J

Raw material MI cable

WIKA data sheet IN 00.23 ∙ 09/2016

Thermocouple wire: Ø 1 mm or Ø 3 mm
Insulation:
Ceramic insulators, ceramic C 610 / mullite

Page 11 of 13

Connecting cables for thermocouples
To bridge the distance between thermocouple andinstrumentation, special connection cables must be usedwith thermocouples.
A distinction is made here between thermocouple cables(the wire material corresponds to the original material of thethermocouple) and so-called compensating cables.
With compensation cables, the wire material corresponds ina limited temperature range to the thermoelectric propertiesof the original thermocouple. These temperature limits arelisted in IEC 60584-3 or ASTM E230. Information about theaccuracy classes of the cables are shown there as well.
The use of these special wire materials is required to avoid“parasitic thermocouples”.

Connecting cable■■ Thermocouple cable
The internal leads of the thermocouple cable are made oforiginal materials of the thermocouple (not available for
precious thermocouples for cost reasons).
The cables are available in the accuracy classes 1 and 2.
■■ Compensating cable
The internal leads of the compensating cable are made ofmaterials which correspond to the thermoelectric propertiesof the original thermocouples. This applies to a temperature
range defined in IEC 60584 / ASTM E230 on the transition
cable ↔ thermocouple, and to the entire length of the cable.
Available only in accuracy class 2.

For thermocouple type B, the use of internal leads made ofcopper is allowed.
Expected error (example): 40 µV / 3.5 °C
This is true within a temperature range of 0 ... 100 °C at
the junction of thermocouple and compensating cable.
The temperature of the measuring point in this example is
1400 °C.
Note:
The potential faults of thermocouple and connecting cable
are added!

Page 12 of 13

WIKA data sheet IN 00.23 ∙ 09/2016

Thermocouple and extension wire colour codes
ASTM E230
ASTM E230
Thermocouple Extension
wire
wire

BS 1843

DIN 43714

ISC1610-198

NF C42-323

IEC 60584-3

IEC 60584-3
Intrinsically
safe

N
J
K
E
T
R
S
B

09/2016 EN© 2013 WIKA Alexander Wiegand SE & Co. KG, all rights reserved.
The specifications given in this document represent the state of engineering at the time of publishing.
We reserve the right to make modifications to the specifications and materials.

WIKA data sheet IN 00.23 ∙ 09/2016

Page 13 of 13

WIKA Alexander Wiegand SE & Co. KG
Alexander-Wiegand-Straße 30
63911 Klingenberg/GermanyTel.
+49 9372 132-0
Fax+49 9372 132-406
info@wika.de
www.wika.de