It is necessary for thermocouple temperature measurement that the electro-motive force (ab- breviated as e.m.f. hereafter) of the thermocouple circuit is precisely measured by a measur- ing instrument. A thermocouple is electrically connected to the instrument by a proper pair of electric cables. IEC 60584-3 standardizes these cables. It specifies identification and manu- facturing tolerances for extension and compensating cables (mineral insulated extension and compensating cables are not included) provided directly to users of industrial processes. These tolerances are determined with respect to the e.m.f. versus temperature relationship of IEC 60584-1. The requirements for extension and compensating cables for use in industrial process control are specified.
Extension and compensating cables may consist of a single strand (solid) wire or multi- stranded wire for which this document is applied. Specification for extension and compensat- ing conductors of forms of rods, flat wires or strips can be established by agreement between suppliers and users.
