Thermocouple Colour Code Standards

In the UK and Europe, the most widely used colour code for Type T thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Brown,
Negative Leg = White,
Outer Sheath (Jacket) = Brown,
Thermocouple Connector Colour = Brown

Occasionally in the UK, American ANSI colours may be found which have a blue outer sheath with blue and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type J thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Black,
Negative Leg = White,
Outer Sheath (Jacket) = Black,
Thermocouple Connector Colour = Black

Occasionally in the UK, American ANSI colours may be found which have a black outer sheath with white and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type N thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Pink,
Negative Leg = White,
Outer Sheath (Jacket) = Pink,
Thermocouple Connector Colour = Pink

Occasionally in the UK, American ANSI / ASTM colours may be found which have a black outer sheath with white and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type E thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Purple,
Negative Leg = White,
Outer Sheath (Jacket) = Purple,
Thermocouple Connector Colour = Purple

Occasionally in the UK, American ANSI colours may be found which have a purple outer sheath with purple and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type R thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Orange,
Negative Leg = White,
Outer Sheath (Jacket) = Orange,
Thermocouple Connector Colour = Orange

Occasionally in the UK, American ANSI colours may be found which have a green outer sheath with black and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type S thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Orange,
Negative Leg = White,
Outer Sheath (Jacket) = Orange,
Thermocouple Connector Colour = Orange

Occasionally in the UK, American ANSI colours may be found which have a green outer sheath with black and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the most widely used colour code for Type B thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Grey,
Negative Leg = White,
Outer Sheath (Jacket) = Grey,
Thermocouple Connector Colour = Grey

Occasionally in the UK, American ANSI colours may be found which have a grey outer sheath with grey and red conductors as shown below. The colours of connectors for both IEC and ANSI match the outer sheath colour of the cable. You may also come across some old redundant colours such as the obsolete BS1843 standard and these are shown in the table below:

In the UK and Europe, the official colour code for Type C thermocouple cable is to the international IEC 60584-3 standard which is as follows:

Positive Leg = Red *
Negative Leg = White *
Outer Sheath (Jacket) = Red,

* It should be noted that Type C has only very recently been included in the IEC 60584-3 standard. As such, a lot of cable still in use and being supplied could well be to the historical industry accepted standard shown in the table below. If you are in any doubt about colour codes, please contact one of our engineers who will be pleased to assist you.

There are a few "non-standardised industry norms" that you may come across, these mainly relate to the more specialised thermocouples types G, C and D and are shown below