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Outdoor lighting systems can be installed at the outside walls ness of at least 5 cm in a radius of 3 m around the lamp pole
of a building and in open terrain. In both cases, it must be (Figure 9.2.1).
checked whether the outdoor lighting systems are located in
lightning protection zone LPZ 0 A or LPZ 0 B . Outdoor lighting To reduce step voltages, the IEC 62305-3 (EN 62305-3)
systems in LPZ 0 A are subjected to direct lightning strikes, im- standard requires, for example, potential control. To this end,
pulse currents up to the full lightning current and the full light- four rings are buried around the lamp pole at distances of
ning field. In LPZ 0 B they are protected against direct lightning 1.0 m; 4.0 m; 7.0 m and 10.0 at depths of 0.5 m; 1.0 m;
strikes, however, they are subjected to impulse currents up to 1.5 m and 2.0 m. These rings are interconnected by means of
partial lightning currents and the full lightning field. four connecting cables at right angles to each other and are
connected to the lamp pole (Figure 9.2.2).
Lamp poles in LPZ 0 A have to be connected to one another in
the soil and to the earth electrodes of the buildings by means
of suitable earthing conductors. It is advisable to use Table 7 Material Configuration Earthing conductor
of IEC 62305-3 (EN 62305-3) when selecting the materials
and cross-sections to be used. Table 9.2.1 shows an excerpt Copper Stranded / 50 mm 2
of the before mentioned table for practical use. The relevant round / tape
material must always be selected with regard to its corrosion Round, galvanised 78 mm 2
resistance. Steel Tape, galvanised 90 mm 2
It must be checked in each individual case whether measures
to reduce the probability of electric shock hazard resulting Stainless Round 78 mm 2
from touch and / or step voltage must be taken. steel (V4A) Tape 100 mm 2
Table 9.2.1 Minimum dimensions of earthing conductors for inter-
To reduce touch voltages, the IEC 62305-3 (EN 62305-3) connecting lamp poles in LPZ 0 A and connecting lamp
standard requires, for example, an asphalt layer with a thick- poles to the earth-termination systems of the buildings

asphalt layer
≥ 5 cm

±0
–0.5 m –1.0 m
–1.5 m
–2.0 m
3 m 3 m
1 m
4 m
7 m
10 m

Figure 9.2.1 Standing surface insulation to Figure 9.2.2 Potential control to reduce step voltage in case of a lightning strike to a lamp
reduce the risk of touch voltage pole
in case of a lightning strike to
a lamp pole

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