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The function of emergency alarm systems (fire or burglar alarm All these factors cause unnecessary costs and can be prevent-
systems) is to actively produce an alarm in the event of danger ed if possible causes of false alarms are recognised at an early
and remain passive when there is no danger. Malfunction of design stage and are eliminated by taking suitable preventive
these systems (no alarm is produced if there is danger or alarm measures. For this purpose, the German Insurance Association
is produced if there is no danger) is undesired and expensive (GDV) published the VdS 2833 guideline, which describes light-
and is responsible for several hundred millions of euros in ning and surge protection for emergency alarm systems.
losses annually. Moreover, false alarms have the following Coordinated lightning and surge protection prevents false
consequences: alarms or the destruction by atmospheric discharges or switch-
¨ If false alarms frequently occur, the operator can no longer ing overvoltages and increases the availability of the systems.
rely on the system and questions the significance of such a When installing emergency alarm systems which are not re-
system and the associated investment. quired by the building law, the VdS guideline should be used
¨ Security personnel start ignoring the alarm messages. for designing and installing these emergency alarm systems
¨ Neighbours are disturbed by acoustic alarms. and for defining individual measures between the installer and
operator.
¨ Emergency staff (e.g. fire brigade) is unnecessarily called Many of today’s emergency alarm systems have an increased
out. surge immunity according to IEC 61000-4-5 (EN 61000-4-5) on
¨ Triggering of fire extinguishing systems cause interruption the primary lines, secondary lines and mains voltage cables.
of operations. Nevertheless, only external and internal lightning protection

magnetic contacts

glass break detector

IR detector 1

IR detector 2
seismic detector
hold-up button 1+2
alarm panel
block lock 1
arming acknowledgement 1
block lock 2
arming acknowledgement 2 burglar alarm system
access control reader
buzzer 1 arming device
EU
horn 1

TE
horn 2
fixed-line
operator
flashlight
230 V

Figure 9.9.1 Lightning and surge protection for a burglar alarm system with pulse polling technology

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