Compensation Wire

Thermocouples are among the most common temperature sensors in industry. But they have a fundamental limitation. The reference junction (cold junction) temperature must stay constant. Otherwise measurement results have errors. In reality, the cold junction is usually in the control room or junction box. Ambient temperature changes are unavoidable. Anhui Tiankang's compensation wire uses special alloy conductors with thermoelectric characteristics matching the corresponding thermocouple indexing. This extends the thermocouple cold junction from the field to the more temperature-stable control room. The wire cancels measurement errors from lead wire temperature differences. This ensures the DCS or instrument reads accurate temperature data. Compensation wire can only be used with thermocouples. It cannot be used for ordinary power or switch signal transmission.

The first priority in selecting compensation wire is correctly matching the indexing. Different thermocouple indexing has different thermoelectric characteristic curves. The compensation wire alloy material must exactly correspond. Different types cannot be mixed. K indexing (nickel-chromium/nickel-silicon) is the most commonly used type. It suits general temperature measurement in boilers, power plants, and chemical plants. S indexing (platinum-rhodium 10/platinum) is used for high-temperature precision measurement, heat treatment, and nuclear applications.

Compensation wire products include B indexing (platinum-rhodium 30/platinum-rhodium 6) for ultra-high temperature kilns. E indexing (nickel-chromium/copper-nickel) has high sensitivity at low temperatures. It suits precision measurement from -200 to 800°C. T indexing (copper/copper-nickel) suits low-temperature refrigeration. Cross-sections from 0.5mm² to 2.5mm² are available. Multiple pairs (1, 2, 3 pairs) can be integrated into one cable for simultaneous transmission of multiple thermocouple signals.

For structure selection, standard compensation wire (KC/SC/BC etc.) uses PVC insulation. Working temperature is 70°C. This suits short-distance wiring inside control rooms. When the cable path passes near VFDs, motors, or other strong interference sources, shielded compensation cable (KCVP/SCVP) is required. Copper wire braid shielding effectively resists electromagnetic interference and prevents temperature signal drift.

For heat treatment furnaces and kiln high-temperature areas, fluoroplastic high-temperature compensation cable (KCF/SCFP) is available. FEP insulation withstands 200°C. It is also oil-resistant and acid/alkali-resistant. For direct burial underground or outdoor installation, KCVP22/SCVP22 adds a steel tape armor layer. For subways, utility tunnels, and nuclear applications with strict fire requirements, WDZ-KCYP low-smoke halogen-free flame-retardant type is mandatory.

All products strictly follow GB/T 4989 and IEC 60584 standards. Each batch undergoes thermoelectric characteristic comparison testing against standard thermocouples. This ensures compensation accuracy meets requirements. Export shipments include CE certification and IEC standard test reports.