MI 2893 / MI 2892 / MI 2885
EN 50160 Standard Overview
211
11
3,5 %
15
1,0 %
6..24
0,5 %
13
3,0 %
21
0,75 %
17
2,0 %
19
1,5 %
23
1,5 %
25
1,5 %
5.2.5
Interharmonic voltage
The level of interharmonics is increasing due to the development of frequency converters and similar
control equipment. Levels are under consideration, pending more experience. In certain cases
interharmonics, even at low levels, give rise to flickers (see 5.2.7), or cause interference in ripple control
systems.
5.2.6
Mains signalling on the supply voltage
In some countries the public distribution networks may be used by the public supplier for the
transmission of signals. Over 99 % of a day the 3 s mean of signal voltages shall be less than or equal to
the values given in the following figure.
Figure 177: Mains signalling voltage level limits according to EN50160
5.2.7
Flicker severity
Under normal operating conditions, in any period of one week the long-term flicker severity caused by
voltage fluctuation should be P
lt
≤
1 for 95 % of the time.
5.2.8
Voltage dips
Voltage dips are typically originated by faults occurring in the public network or in network users’
installations. The annual frequency varies greatly depending on the type of supply system and on the
point of observation. Moreover, the distribution over the year can be very irregular. The majority of
voltage dips have duration less than 1 s and a retained voltage greater than 40 %. Conventionally, the
dip start threshold is equal to 90 % of the nominal voltage of the nominal voltage. Collected voltage dips
are classified according to the following table.
Table 144:Voltage dips classification
