Cable and wire technology

How to extend thermocouple wire?

How to extend the thermocouple wire? This requires the use of thermocouple compensation wires, a pair of insulated wires with the same nominal value of the thermoelectromotive force of the matched thermocouple within a certain temperature range (including normal temperature), and use them to connect the thermocouple and measure Device to compensate for the error caused by temperature changes at the junction between them and the thermocouple. So what are the things to pay attention to?
Precautions for Compensation Wire
1. Selection of compensation wire
The compensation wire must be correctly selected according to the type of thermocouple used and the occasion used. For example, the compensation wire of the k-type couple should be selected according to the use occasion and operating temperature range. With an ambient temperature of 70 degrees, PVC is selected as the sheath layer. If the ambient temperature reaches more than 100 degrees Celsius, you need to choose Teflon as the sheath layer.
2. Use length
Because the signal of the thermocouple is very weak, it is in the microvolt level. Temperature fluctuations will occur when the control is severe.
According to our experience, it is usually better to control the length of the thermocouple compensation wire within 15 meters. If it exceeds 15 meters, it is recommended to use a temperature transmitter to transmit the signal. The temperature transmitter converts the potential value corresponding to the temperature into a direct current for transmission, which has strong anti-interference.
4. Wiring
Compensation wire wiring must be far away from power lines and interference sources. Where crossing is unavoidable, the crossing method should also be adopted as much as possible, not parallel.
5. Shielded compensation wire
In order to improve the anti-interference of the thermocouple connecting wire, shielded compensation wire can be used. For occasions with many on-site interference sources, the effect is better. However, the shielding layer must be strictly grounded, otherwise the shielding layer will not only not play a shielding role, but will enhance interference.

Compensation wire alloy wire and insulation color requirements

Compensation number

Cable model

Combined with thermoelectricity

The index of even

Compensation wire alloy wire

Insulation color

positive electrode

negative pole

positive electrode

negative pole


S (Platinum Rhodium 10 platinum)

SPC (copper)

SNC (copper nickel)




N (nicrsi Nisi)

NPC (iron)

NNC (copper nickel)




T (copper constantan)

TPC (copper)

TNC (copper nickel)




K (NiCr Nisi)

KPX (NiCr)

KNX (copper nickel)




E (Ni Cr Cu Ni)

EPX (nickel chromium)

ENX (copper nickel)




J (Fe Cu Ni)

JPX (iron)

JNX (copper nickel)




T (copper copper nickel)

TPX (copper)

TNX (copper nickel)



Order requirements

When ordering, it is necessary to indicate the model, specification, core section, number of cores, shielding method and quantity
Example: KX-GS-VVP-2*1.5MM2 means k type thermocouple cable, GS means normal grade, VV means both insulation and sheath are PVC, P means copper wire braided shield, anti-signal interference
KX-HS-FFP-2*2*1.5, means K-type compensation wire, HS means precision level, FF means Teflon insulation and sheath layer, P means copper wire braided shield, which is suitable for use in double thermocouples on.
For more thermocouple compensation wires, please refer to our detailed introduction,thermocouple extension cable.


Contact: Mr Li

Phone: +86-18226665885

Tel: +86-0550-7788337


Add: No.20# RenHe South Road,TianChang,AnHui Province,China

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