IEC 61156-5:2020, Multicore and symmetrical pair/quad cables for digital communications – Part 5: Symmetrical pair/quad cables with transmission characteristics up to 1 000 MHz – Horizontal floor wiring – Sectional specification.IEC 61156-5:2020 pdf free download.
This part of IEC 61156 describes the cables intended primarily for horizontal floor wiring as defined in ISO/IEC 11801 (all parts).
It covers cable designs comprising individually screened, common screened and unscreened pairs or quads. The transmission characteristics and the frequency range (see Table 1) of the cables are specified at 20 °C.
6.2.9 Current-carrying capacity
The maximum current-carrying capacity is not specified but may be indicated in the relevant detail specification. Further guidance with respect to current carrying capacity is provided by ISO/IEC TS 29125 and the test method described in IEC 61156-1-4.
For those frequencies where the calculated value of TCL is greater than 50 dB, the requirement shall be 50 dB. TCL requirements for frequencies higher than 250 MHz may be defined in the detail specification.
The minimum equal-level far-end unbalance attenuation (equal-level transverse conversion transfer loss or EL TCTL) for all categories shall not be less than the value obtained from Equation (7) to Equation (9) for all frequencies,f in the range from 1 MHz to 30 MHz.