BS IEC 62153-4-16 is a safety standard on metallic communication cable test methods.
BS IEC 62153-4-16 describes a method to extrapolate the test results of transfer impedance to higher frequencies and the test results of screening attenuation to lower frequencies when measured with the triaxial set-up according to IEC 62153-4-3 (method B) respectively IEC 62153-4-4.
Note: A similar approach to extrapolate the test results of transfer impedance to higher frequencies was already described in IEC 61196-1:1995 Subclause 12.2. This method is applicable for homogenous screens, i.e. screens having a transfer impedance directly proportional to length. The transfer impedance may have any frequency behaviour, i.e., it could have a behaviour where it does not increase with 20 dB per decade as observed for screens made of a foil and a braid.
BS IEC 62153-4-16 on the extension of the frequency range to higher frequencies for transfer impedance and to lower frequencies for screening attenuation measurements using the triaxial set-up is relevant to:
The triaxial set-up is used to measure both the surface transfer impedance (IEC 62153-4-3) and the screening attenuation (IEC 62153-4-4).
The transfer impedance is in general measured with a coupling length of max. 0,5 m resulting in an upper-frequency limit of around 100 MHz, whereas the screening attenuation is in general measured with a coupling length of 2 m to 3 m resulting in an upper-frequency limit for the transfer impedance of around 10 MHz and a lower frequency limit for the screening attenuation of around 100 MHz. BS IEC 62153-4-16 assists in knowing the frequency behaviour of the triaxial set-up which may help in converting a screening attenuation measurement to transfer impedance and vice versa.
Overall, BS IEC 62153-4-16 is useful as it helps in determining the impedance and relative dielectric permittivity of the outer circuit (tube).
IEC 62153-4-16 Ed. 1.0
IEC 62153-4-16:2016