Every electrical device plugged into the mains can be disturbed via noise emitted by another electrical apparatus

Different test standards are used for the immunity to conducted disturbances :

• CEI 1000-4-4 : Electrical fast transient/burst immunity test
• CEI 1000-4-5 : Surge immunity test
• CEI 1000-4-6 : Immunity to conducted disturbances, induced by radio-frequency fields.
• CEI 1000-4-11 : Voltage dips, short interruptions and voltage variation immunity tests.

The test relating to the standard CEI 1000-4-6 is described in the chapter 'Radiated immunity'.

Here, we are going to describe only the test showing high frequency characteristics that relates to the standard CEI 1000-4-4. This test is both cheap (no faraday chamber is needed) and representative : if the equipment passes this test, it will probably work correctly on site.