Outdoor lighting can be installed at the outerwalls of buildings as well as on open site. In anycase it has to be considered whether the outdoorlighting is located in lightning protection zone LPZ0A or in lightning protection zone LPZ 0B. Outdoorlighting in LPZ 0A is at risk of direct lightningstrikes, impulse currents up to the whole lightningcurrent and of the whole field of the lightningflash. In LPZ 0B they are protected against directlightning strikes, however, at risk of impulse cur-rents up to partial lightning currents and thewhole field of lightning.

Lamp poles in lightning protection zone LPZ 0Ahave to be interconnected underground and theyhave to be connected with the earth electrodes ofthe buildings or structures via permissible earthingconductors. The recommended materials, dimen-sions and cross sections are indicated in Table 7 of

IEC 62305-3 (EN 62305-3). Table 9.2.1 shows anexcerpt of it for practical use. The material to beused always has to be selected with regard toprobable corrosion.

Measures to reduce the risk of electric shock haz-ard due to touch and/or step voltage are subjectto individual examination.Analogously to IEC 62305-3 (EN 62305-3) therequired measure to reduce the touch voltages is,for example, an asphalt layer of at least 5 cm thick-ness or 15 cm gravel, 3 m around the lamp pole(Figure 9.2.1).

In IEC 62305-3 (EN 62305-3) also the potential con-trol, for example, is mentioned as measure toreduce step voltages. In this case four rings areinstalled in the distances 1.0 m, 4.0 m, 7.0 m, and10.0 m, and in the corresponding depths of 0.5 m,

1.0 m, 1.5 m, and2.0 m around thelamp pole. Theserings are inter-connected by fourconnecting leadswhich are stag-gered by 90 ° andalso with thelamp pole (Fig-ure 9.2.2).

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9.2 Lightning and surge protection for outdoor lightingsystems

Material Form Earthing conductor Notes

Copper cableroundstrip

50 mm2

50 mm2

50 mm2

min. wire thickness 1.7 mmØ 8 mmmin. thickness 2 mm

Steel round galvanised 50 μmstrip galvanised 70 μm

Ø 10 mm90 mm2

-min. thickness 3 mm

StainlessSteel

roundstrip

Ø 10 mm100 mm2

-min. thickness 2 mm

3 m 3 m

asphalt layer≥ 5 cm

Fig. 9.2.1 Insulation of the place around the lamp pole to reduce the risk of touch voltage in case of lightning strike

Table 9.2.1 Min. dimensions of earthing conductors for interconnecting lamp poles in LPZ 0A and for connecting tothe earth-termination system of the building or structure

The following types of lightning current and surgeprotective devices are installed at the boundary of the lightning protection zone LPZ 0A – LPZ 1 or LPZ 0B – LPZ 1.All outdoor lightings in lightning protection zoneLPZ 0A shall be protected by lightning currentarresters Type 1 to be installed at the entrance tothe building or structure. This lightning protectionzone to be determined, requires “to approach”the corresponding rolling sphere from all possibledirections to the outdoor lighting. If it is touched

by the rolling sphere, the outdoor lighting is inlightning protection zone LPZ 0A (Figure 9.2.3 andFigure 9.2.4).

Before installing lightning current arresters Type 1,it has to be checked, whether the circuits of theoutdoor lighting are already protected by an ener-gy coordinated SPD Type 2 in the current distribu-tion board, if not, combined lightning current andsurge arresters are recommended to be installed atthe lightning protection zone boundary.

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Fig. 9.2.2 Potential control to reduce the arising step voltage at lightning strikes into a lamp pole

Fig. 9.2.3 230 V wall lamp as outdoor lighting in lightning protection zone LPZ 0A

-0.5 m

1 m

4 m

± 0

-1.0 m-1.5 m

-2.0 m

7 m10 m

Lightning current arresters

Combined lightning currentand surge arresters

TN systemDB 1 255 H (2x), Part No. 900 222

TT systemDB 1 255 H, Part No. 900 222DGP BN 255, Part No. 900 132

TN systemDV M TN 255, Part No. 951 200TT systemDV M TT 2P 255, Part No. 951 110

radius of therolling sphere

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Lightning current arresters

Combined lightning currentand surge arresters

TNC systemDB 3 255 H, Part No. 900 120TNS systemDB 3 255 H, Part No. 900 120DB 1 255 H, Part No. 900 222

TNC systemDV M TNC 255, Part No. 951 300TNS systemDV M TNS 255, Part No. 951 400

TT systemDB 3 255 H, Part No. 900 120DK 35, Part No. 900 699DGP BN 255, Part No. 900 132

TT systemDV M TT 255, Part No. 951 310

radius of therolling sphere

TN systemDG M TN 275, Part No. 952 200

TT systemDG M TT 2P 275, Part No. 952 110

radius of the

rolling sphere

TNC systemDG M TNC 275, Part No. 952 300TNS systemDG M TNS 275, Part No. 952 400TT systemDG M TT 275, Part No. 952 310

radius of the

rolling sphere

Fig. 9.2.4 Lamp pole with 3 x 230/400 V outdoor lighting in lightning protection zone LPZ 0A

Fig. 9.2.5 230 V wall lamp as outdoor lighting in lightning protec-tion zone LPZ 0B

Fig. 9.2.6 Lamp pole with 3 x 230/400 V outdoor lighting in light-ning protection zone LPZ 0B

All outdoor lightings in lightning protection zoneLPZ 0B shall be protected by surge protectivedevices Type 2, to be installed at the entrance tothe building or structure. This lightning protectionzone to be determined, requires “to approach”

the corresponding rolling sphere from all possibledirections to the outdoor lighting, which in thiscase, may not be touched by the rolling sphere(Figures 9.2.5 and 9.2.6).

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