Dalian Bocon Science & Technology Co., Ltd Address No.782, Huangpu Road, Hi-Tech Zone, Dalian, China 116023 Tel:86-411-84793453,84793775 Fax:86-411-84821017,84799763 Web:www.bocondalian.com Extension wires Applications Extension wires are a pair of insulated wires with protecting sheath, which have the same or similar thermoelectric property as that of the thermocouple they are connected to in certain temperature range. They transfer the reference junction of the thermocouple to the other end of the wires, usually to an instrument, to form a measurement system. Classification Classified by composition: C (compensating extension wires) and X (extension wires); Classified by tolerance: standard and S (special); Classified by working temperature: G (general) and H (heat-resisting); Classified by application condition: BC (general purpose), BCR (soft cable), BCP (shield cable) and BCRP (soft shield cable); Shield cable may be divided into electric shield and magnetic shield. Electric shield cable includes high frequency shield and intermediate frequency shield cable. Working temperature range and tolerance (Quoted from ASTM standard) Note: B. Proprietary alloy compensating extension wire is available for use over a wide temperature range. C. Special compensating extension wires are not necessary with Type B over the limited temperature range of 0~50℃ (32~125℉), where the use of Cu/Cu conductors introduces no significant error. For a somewhat large temperature gradient of 0~100℃ (32~210℉) across the extension portion of the circuit, the use of Cu/Cu extension wires may result in small errors, the magnitude of which will not exceed the tolerance values given in the table above for measurements above 1000℃ (1800℉).

Number of pairs of wires 5 cross section Construe tion R: Flexible strand wire Material of protecting sheath B : Alkali-free fiber slass Insulation material Type of extension wire C: Compensating extension wire Matched thermocouple type