1 Scope

Multi-element metallic communication and control cables are often designed with metallic screen against harmful effects of electromagnetic fields e.g. generated in the environment of electric power and electrified railway lines [1] 1.

This part of IEC 62153 applies to the testing of the reduction factor of multi-element metallic cables used in analogue and digital communication and control. The described method is generally applicable to all screened metallic cables.

The reduction factor describes the screening effectiveness of a cable screen at frequencies below 1 kHz with a ratio of voltages describing the screened and unscreened situation. During the measurement, the cable under test is connected to a specific current loop arrangement.