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KNX
KNX 230 V / 50 Hz

M
induction loop

induction loop MEB

230 V / 50 Hz

Figure 9.10.2 Induction loop formed by two KNX bus devices Figure 9.10.3 Induction loop formed by one KNX bus device installed
supplied with low voltage at a metal construction or pipe

3 x 230/400 V KNX

KNX
M SDB KNX
Type Part No.
SEB
DV ZP TNC 255 (TN-C system) 900 390
DV ZP TT 255 (TN-S/TT system) 900 391
DG M TNS 275 (TN-S system) 952 400
DG M TT 275 (TT system) 952 310
BT 24 925 001
buried in the ground
BXT ML2 B 180 920 211
+ BXT BAS + 920 300
Figure 9.10.4 Lightning equipotential bonding at the entrance point of the KNX bus cable into the building and surge protective devices
installed at the distribution board of the KNX system and at the actuator of the heater

If the bus cable is routed between different buildings in a Structure without external lightning protection
lightning current carrying and shielded duct / metal pipe that system
is earthed on both ends, lightning equipotential bonding does If there is a risk of nearby lightning strikes, it is advisable to
not have to be established for the KNX cable extending be- install lightning current carrying combined arresters at the en-
yond the buildings and it is sufficient to install surge arresters trance point into the building to protect the incoming power
(Figure 9.10.5). cable (Figure 9.10.6).

314 LIGHTNING PROTECTION GUIDE www.dehn-international.com