Alarm system

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The term hazard alarm system (GMA) summarizes all alarm systems that are able to recognize hazards independently or to process user inputs on hazards and report them using telecommunications technology. In Germany, DIN VDE 0833 Part 1 is the central standard for planning, setting up and operating these systems. The purpose is to reliably identify and report the dangers to property and life from burglary , assault and fire . For fire alarm systems , Part 1 applies together with Part 2 of DIN VDE 0833. DIN VDE 0833 Part 3 (VDE 0833-3), on the other hand, applies together with Part 1 for intrusion and hold-up alarm systems .


The history of the modern alarm system began on June 21, 1853: The first electro-magnetic alarm system was patented by Augustus Russell Pope, a tinkerer from Somerville near Boston (USA). It responded to the closing of a parallel circuit. Edwin Holmes bought the rights to Pope's invention in 1857 and founded the "Holmes Electric Protection Company". Thanks to intensive advertising, Edwin Holmes achieved the economic breakthrough for his “burglar alarm telegraph”. By using the New York telegraph network, he was even able to set up the first alarm control system. In the 1860s, telegraph technician and inventor Edward A. Calahan worked on a system for more effective alerting that could also get help. He divided New York into districts, each of which was connected to such a central emergency number. In 1871, Calahan helped set up the American District Telegraph (ADT) Company. The Calahan-type emergency call boxes quickly became the standard in police and fire protection, but intelligence services also used them. The development stagnated, but the technology became more and more affordable and, especially in the United States, was increasingly gaining acceptance in the private sector.

In the 1970s, the first PIR motion detectors were integrated into the alarm systems. In the 1980s and 1990s, alarm systems became increasingly popular in Europe. Finally, at the beginning of 2000, the first series of wireless radio alarm systems came onto the market and popularized alarm technology. In recent years, alarm systems have followed the trend towards networking: Modern alarm systems combine wired and wireless alarms with network technology. In addition, the new systems have recently also been integrating video surveillance via IP: The boundaries between video surveillance and alarm technology (so-called "alarm inputs / outputs"), which were previously easily bridged using bus technology, are thus eliminated. Manufacturers are also currently trying to introduce the prevention concept of mechanical security into alarm technology under the term “ mechatronics ” (which has not yet been developed for alarm technology) .

Components of a GMA

A GMA consists of at least the following parts:

A GMA must have two independent energy sources. Fault reports and alarms must be forwarded to a permanently manned office. This is often perceived by control centers .

According to DIN VDE 0833, an operating log must be kept for hazard alarm systems . Upon completion ( technical acceptance ), the installer issues an installation certificate to the operator .

Function types

Hazard alarm systems can be operated with the following three technologies:

  • Direct current technology: here the current flows within the EMA between 2 points via a common detector
  • Bus technology: all detectors are connected via two common wire pairs, which on the one hand function as a data line and on the other hand enable the power supply for other detectors.
  • Radio technology: the functionality of such EMAs is almost identical to that of bus technology. The only difference is that there is no wiring and the signals are transmitted by radio.

Alert types

In section 3.1 Terms , four types of alarms are defined in DIN VDE 0833-1:

Internal alarm (house alarm )
On-site alarm with acoustic and / or optical signaling devices, which is directed at people present to warn of a danger
External alarm
On-site alarm to avert danger
Remote alarm ( operational alarm )
Alarm that is directed to a not-on-site commissioned assistance center, e.g. B. fire brigade, police or emergency and service control center
False alarm
No danger underlying alarm

Fire alarm systems

DIN VDE 0833-2 deals with two types of alarm:

  • Remote alarm
  • Internal alarm

Assault and intrusion alarm systems

DIN VDE 0833-3 refers to DIN EN 50131-1 VDE 0830-2-1 with regard to the requirements for alarm output. There are three types of alarm in common usage:

Silent alarm
This alarm is mainly used in attack alarm systems (ÜMA). This is for personal protection, since a perpetrator is to be classified as unpredictable and should not find out that threatened people have triggered an alarm. No signaling devices are activated in the event of a silent alarm. However, an emergency call and service control center or the police are immediately alerted in accordance with the ÜEA guideline .
Audible alarm
A loud signal tone sounds at this local alarm . The standards refer to this as an external alarm. This is intended to warn people present in the property or to put offenders who have penetrated the property as quickly as possible, which (if successful) results in damage minimization.
According to DIN VDE 0833-3, alarms via acoustic signaling devices to the anonymous public are strictly prohibited. External acoustic signaling devices can be installed in the security area to deter offenders . Installation outside of the security area is only permitted in justified exceptional cases. If the neighbors are significantly disturbed by frequent false alarms , the external alarm must be switched off.
Optical alarm
Optical external signaling devices can also be installed. They must be clearly visible to the assistants and clearly identify the monitored object. The visual display may be unlimited and goes out when the triggered security area is disarmed or after the alarm is cleared.

According to DIN VDE 0833-3 as well as the guidelines of VdS Schadenverhütung GmbH and the police ÜEA guideline, if a burglar alarm is triggered, a remote alarm is generally sent to a commissioned assistance center (e.g. emergency and service control center) and only an external alarm via an acoustic external signal transmitter provided within the security area. By triggering a loud alarm inside the building, the perpetrators are also “put under psychological pressure” so that they can give up their act more quickly due to the noise. According to DIN VDE 0833-3, acoustic external signaling devices outside the security area (ie on the outside wall of the building) are only permitted in exceptional cases, e.g. B. remote object, deficits in alarm transmission security, permissible.

This ensures that an alarm verification (alarm pre-test) takes place from there due to the forwarding of the alarm to an auxiliary body. It is therefore no longer necessary to issue an alarm on site via acoustic external signaling devices outside the security area and thus to the anonymous public (e.g. neighbors), because the police would certainly be informed from there, which then may cause false alarm charges.

Alarm verification

After an alarm has been issued, the actual circumstances of the alarm must be ascertained as part of the alarm verification , because it can be a real hazardous situation or a false alarm .

Individual evidence

  1. a b c DIN VDE 0833-1 VDE 0833-1: 2014-10. In: Retrieved July 24, 2020 .
  2. ^ August Bremicker Söhne KG: The history of the alarm system
  3. Function types of alarm systems. Retrieved March 30, 2018 .
  4. DIN VDE 0833-2 . Alarm systems for fire, burglary and hold-up - Part 2: Specifications for fire alarm systems. VDE Verlag, October 2017, p. 43 .
  5. DIN VDE 0833-3 . Alarm systems for fire, intrusion and hold-up - Part 3: Specifications for intrusion and hold-up alarm systems. VDE Verlag, September 2009, p. 18 .
  6. Thomas Laasch, Erhard Laasch: Building services basics, planning, execution . Vieweg Springer Verlag, 2013, ISBN 3-8348-1260-9 , p. 437 .
  7. a b c DIN VDE 0833-3 VDE 0833-3: 2009-09. In: Retrieved July 24, 2020 .
  8. OLG Schleswig, Az. 4U 192/78.