Chapter A General rules of electrical installation design

J - Protection against voltage surges in LV
1
Equipment to be
protected
2
Determine the
architecture of the
building
3
Risk level of
the impact of a
lightning strike
Choice of type of
surge arrester
Domestic equipment
Type 2
10 kA
Detached house,
Professional
premises
Type 2
40 kA
Type 1
25 kA
+
Type 2
40 kA
Audio-video, computers,
household appliances,
burglar alarm, etc.
Type 1
25 kA
+
Type 2
40 kA
Apartment, small
semi-detached
house
Type 2
10 kA
Schneider Electric - Electrical installation guide 2008
Communal part of a
building
Note:
Type 1: very high discharge capacity surge arrester used with a lightning conductor with an impact level of and .
Type 2: surge arrester used in cascade behind a type 1 surge arrester or alone in zone and .
Fig. J32 : Domestic equipment
Lightning also propagates through
telecommunications networks.
It can damage all the equipment connected to
these networks.
4 Choosing a protection device
Type 2
40 kA
Protection of telecommunications equipment
Type 2
65 kA
Choice of surge arresters PRC
Analogue telephone networks < 200 V b
Type 1
25 kA
+
Type 2
40 kA
Type 1
25 kA
+
Type 2
40 kA
J19
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