IEC 61000-2-4 is related to conducted disturbances in the frequency range from 0 kHz to 150 kHz. It gives compatibility levels for industrial locations, with a nominal voltage of up to 35 kV and a nominal frequency of 50 Hz or 60 Hz.
The compatibility levels specified in IEC 61000-2-4 apply at the in-plant point of coupling (IPC). The level of the low-frequency disturbances at the terminals of equipment receiving its supply from the IPC is generally assumed to be similar to the disturbance level at the IPC itself. However, in some situations, this is not the case, particularly when a long feeder is dedicated to the supply of a particular load, or when a disturbance is generated or amplified within the installation of which the equipment forms a part.
Compatibility levels are specified for the types of low-frequency electromagnetic disturbances expected at any in-plant point of coupling (IPC) within industrial locations, for guidance in the definition of:
a) limits for disturbance emissions in industrial power distribution systems (including the planning levels defined in 3.1.5);
b) immunity levels for the equipment within these systems.
The disturbance phenomena considered are:
– voltage deviations;
– voltage dips and short interruptions;
– voltage imbalance;
– power-frequency variations;
– harmonics up to order 40;
– interharmonics up to the 40th harmonic;
– voltage components above the 40th harmonic up to 150 kHz;
– d.c. component;
– transient overvoltages.
The compatibility levels are given for different classes of environment determined by the characteristics of the supply network and loads.
