5.4.2 External lightning protectionsystem for a residential house

Fig. 5.4.2.1 illustrates the design of theexternal lightning protection system fora residential house with attachedgarage.Fig. 5.4.2.1 and Table 5.4.2.1 show exam-ples of the components in use today. No account is taken of the measuresrequired for an internal lightning protec-tion system such as lightning equipoten-tial bonding and surge protection (seealso Chapter 6).

Particular attention is drawn to DEHN’sDEHNsnap and DEHNgrip programme ofholders.The DEHNsnap generation of syntheticholders (Fig. 5.4.2.2) is suitable as a basiccomponent (roof and wall). The cap sim-ply snaps in to fix the conductor in theholder while still being loosely guided.The special snap-in technique exerts nomechanical load on the fastening.DEHNgrip (Fig. 5.4.2.2) is a screwlessstainless steel system of holders whichwas put into the programme to supple-ment the DEHNsnap system of syntheticholders.

This screwless system of holders can alsobe used as both a roof and a wall con-ductor holder for Ø8 mm conductors.Simply press in the conductors and theconductor is fixed in DEHNgrip (Fig. 5.4.2.2).

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Fig. 5.4.2.1 External lightning protection of a residential building

4

5

3

11

7

2

6 8

1213

10

1

15

9

14

16

20

21

19

1718

base part

cap

DEHNgripconductor holder

DEHNsnapconductor holder

Fig. 5.4.2.2 DEHNsnap und DEHNgrip conductor holders

Pos. in Part description Part No.Fig. 5.4.2.1

Bridging bracket made of aluminium 377 006

Bridging braid made of aluminium 377 015

Lead-in earthing rod Ø16 mm 480 150complete 480 175

Rod holder with flange 275 116275 260

Parallel connector 305 000306 020

Cross unit 319 201SV clamps made of St/tZn 308 220SV clamps made of StSt 308 229

Rod holder with cleat and flange 275 260for heat insulation 273 730

Number plate for 480 006marking isolating points 480 005

Air-termination rod with forged tab 100 075with rounded ends 483 075

Rod clamp 380 020

Rod holder with tip 262 130

Earth rod St/tZn 620 150sectional unit with bolt 625 150and hole 620 151

625 151

Impact tip for deep-driven 620 001earth rods 625 001

Connecting clamp for earth rods 620 011unilateral 625 011

for earth rods 620 015625 015

21

20

19

18

17

16

15

14

13

12

11

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Pos. in Part description Part No.Fig. 5.4.2.1

Round conductor Ø8 mm – 840 008DEHNALU, medium-hard, 840 018soft-twistable

Steel strip 30 x 3.5 mm – St/tZn 810 335

Round conductor Ø10 mm – 860 010StSt V4A

Roof conductor holders 202 020for ridge and hip tiles 204 109

204 249204 269206 109206 239

Roof conductor holders 204 149for conductors within 204 179roof surfaces 202 010

202 050202 080206 209206 309

DEHNsnap 204 006DEHNgrip 207 009conductor holder

with cleat and flange 275 160for heat insulation 273 740

Gutter clamp for beads 339 050made of stainless steel 339 059

Single-screw gutter glamp 339 100made of stainless steel 339 109

MV clamp made of Al 390 050MV clamp made of StSt 390 059

Gutter board clamp 343 000

Downpipe clampadjustable for Ø60-150 mm 423 020for any cross sections 423 200

KS connector for connecting conductors 301 000made of StSt 301 009

MV clamp 390 05110

9

8

7

6

5

4

3

2

1

Table 5.4.2.1 Components for external lightning protection of a residential builiding

5.4.3 Application tips for mountingroof conductor holders

Ridge and hip tiles:Adjust roof conductor holders withadjusting screw to suit the dimension ofthe ridge tile (Fig. 5.4.3.1).

The conductor leading can, in addition,be gradually adjusted by means of con-ductor holders from the top centre to thebottom side.(conductor holder can be loosened byeither turning the holder or opening thefixing screw.)

SPANNsnap roof conductor holder withDEHNsnap synthetic conductor holder orDEHNgrip stainless steel conductor hold-er (Fig. 5.4.3.2).

Permanent tension due to stainless steeltension spring. Universal tension rangefrom 180-280 mm with laterallyadjustable conductor leading for Rd8 mm conductors.

FIRSTsnap conductor holder with DEHN-snap synthetic conductor holder for put-ting on existing ridge clamps for dryridges.

For dry ridges, the DEHNsnap conductorholder (1) (Fig. 5.4.3.3) is put on the ridgeclamp already on the structure (2) andtightened manually (only turn DEHN-snap).

Grooved pantiles:The roof conductor holder with pre-formed struts is used for the roof sur-faces. The conductor holder is bent byhand before being hooked into the bat-tens. Additionally, it can also be securedwith nails (Fig. 5.4.3.4).

Smooth tiles (Fig. 5.4.3.5):

Slate roofs:When using it on slate roofs, the internalhook system is bent (Fig. 5.4.3.6) orequipped with a supplementary clamp(Part No. 204 089).

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Fig. 5.4.3.1 Conductor holder with DEHNsnap forridge tiles

Fig. 5.4.3.2 SPANNsnap with plastic DEHNsnap con-ductor holder

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Fig. 5.4.3.3 FIRSTsnap for mounting on existing rid-ge clamps

angled by hand

Fig. 5.4.3.4 Roof conductor holder with preformedbrace - Used on grooved pantiles

Fig. 5.4.3.5 Roof conductor holder with preformedbrace - Used on smooth tiles,e.g. plain tiles

angle the inner latchingfor use on slate roofs

Fig. 5.4.3.6 Roof conductor holder with preformedbrace - Used on slate roofs

Grooved tiles:FLEXIsnap roof conductor holder forgrooved tiles, for direct fitting on thegroove (Fig. 5.4.3.7).

The flexible stainless steel strut is pushedbetween the grooved tiles.By pressing on the top grooved tile, thestainless steel strut is deformed andadapts itself to the shape of the groove.Thus it is fixed tightly under the tile.This application with an aluminium strutmakes it easy to adapt to the shape ofthe groove.A notch is provided for an eventuallyexisting window hook.The strut of the holder can also be naileddown (holes in the strut).

Roof conductor holders with preformedstrut, for hooking into the bottomgroove for pantile roofs (Fig. 5.4.3.8).

Flat tiles or slabs:DEHNsnap conductor holder (1)(Fig. 5.4.3.9) and its clamping device (2) ispushed in between the flat tiles (3) (e. g.plain tile) or slabs and tightened manual-ly (only turn DEHNsnap).

Overlapped constructions:In case of overlapped constructions (3)(e. g. slabs and natural slates), DEHNsnapconductor holder (1) (Fig. 5.4.3.10) withclamping terminals (2) is pushed on fromthe side and secured with a screw driverwhen the holder is open.For slabs laid on a slant, DEHNsnap canalso be turned to allow a plumb conduct-or leading.

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insert the holderunderneath

lift tile

press tileon it

Fig. 5.4.3.7 Conductor holder for direct fitting on theseams

insert the holderunderneath

lift tile

press tileon it

Fig. 5.4.3.8 Roof conductor holder for hanging intothe bottom seam of pantile roofs

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Fig. 5.4.3.9 ZIEGELsnap, for fixing between flat tilesor plates

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Fig. 5.4.3.10 PLATTENsnap roof conductor holderfor overlapped constructions