Permissible levels on networks
Voltage quality - Harmonics

Table 2 shows the compatibility levels for harmonic voltages in low- and medium-voltage networks derived from IEC standards 61000-2-2 and 61000-2-12. The compatibility level is the level of disturbance likely to occur in the environment under consideration, with a low probability of being exceeded (5%).

These figures have no equivalent on high-voltage networks.

Correct operation of electrical networks and the equipment connected to them involves finding a compromise between the disturbances emitted by disturbance-producing equipment and the immunity of equipment sensitive to these disturbances. Compatibility levels are the basis for this compromise.