Alarm false alarm - a notification generated by the alarm system about the occurrence of an alarm event in the absence of obvious signs characterizing it.
For example, for a burglar alarm, an intruder may be an alarm event, for a fire alarm, a fire or related factors (temperature increase, smoke).
I see no reason to list the obvious negative consequences of false alarms, so I propose to consider some of the causes of their occurrence.
- Violations of the signal loop circuit.
- Errors in the design (installation) of the alarm.
- The impact of external factors.
- Electromagnetic interference (interference).
- Design features of alarm sensors.
- Faulty alarm devices.
False alarms of the alarm loop as an electric circuit are caused, first of all, by the presence of bad contacts. The reasons, in fact, are two -
- poor-quality installation (with this, I think, everything is clear)
- a natural increase in contact resistance (over time, the contacts tend to oxidize, screw connections may weaken. The way out is timely and competent maintenance).
The second reason for false positives is due to a violation of the requirements of regulatory documents that determine the rules for installation, design of an alarm system.
False alarms caused by external factors imply alarms from the effect of interference on detectors similar to normalized exposure. For example, for passive IR detectors it can be extraneous light, conventional air flows, etc. Some features of various sensors are described in this section, related articles.
Of course, all this should be taken into account at the design stage, but there are situations when partial redevelopment, installation of new equipment, etc., are carried out in already protected premises.
Point four, of course, can be attributed to external influences, but it is worth mentioning separately. This effect can safely be called the "dark forces of electricity." The insidiousness of electromagnetic radiation and interference lies in the fact that the intensity and place of their influence are purely individual for each object, and even there they are not a constant.
In this case, false positives can occur without any clearly expressed regularity. By the way, false positives from these causes are the result of technological progress. Alarm sensors are constantly becoming more complex, gain new functionality, use new technologies and become more sensitive not only when the required effects are detected, but also third-party effects.
Plus, add here such a factor as the reluctance of manufacturers to increase the cost of production due to the complexity of the design aimed at compensating for such causes of triggering, caused, in turn, by the consumer's desire to get an alarm system for a penny.
The features that affect the false alarms of alarm sensors can also include some individual (for specific types) design flaws, for example, an unsuccessful smoke chamber for fire detectors.
Speaking about malfunctions of alarm devices, naturally I meant "floating" malfunctions (that is, it is - it is not). Also, by the way, the thing is unpleasant, but easier to detect than the previous ones.
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Security systems of various classifications are quite popular in the domestic market. A large number of equipment is installed in order to increase the level of safety in the operation of buildings. However, the use of systems often causes problems. The most common malfunctions are considered false alarms when working in active mode. In such cases, it is important to understand in detail the principles of the device systems and make appropriate decisions to eliminate all defects.
Why is the alarm in the building falsely triggered. Technical problems
Almost all problems with alarms inside buildings arise due to an improper design for installation or incorrect selection of materials that are used to equip systems. Most often, the main problem is the connection cable for supplying signals to the main nodes and sensors. With improper design, the wire is laid with a large number of bends and without observing the recommendations for the temperature regime of operation. The problem is especially relevant in industrial buildings, where there is large-scale production equipment that emits elevated temperatures during operation. In such cases, the technical loop stratifies after a certain operating time, simultaneously breaking contact. This leads to the fact that the alarm is triggered without the presence of real threats.
In ordinary civilian buildings, the main technical causes of problems with the alarm system are low-skilled installation and improper adjustment of automation equipment. In such cases, unstable operation of the systems can occur immediately after the commissioning of security nodes. Accordingly, the owner does not know why the alarm is falsely triggered and is forced to systematically adjust the operation of the equipment manually. In some situations, a complete refurbishment may be required to troubleshoot, which negatively affects the amount of financial costs.
The main technical reasons why the reed switch may be falsely triggered are:
- Incorrect connection of sensors and power cables. The problem lies in the low qualification of specialists who performed the connection work, as well as in a hurry during installation. Any erroneous connection may reduce the effectiveness of building security. After all, non-compliance with the installation sequence of detectors, sensors (movement, lighting, volumetric triggering), monitors, and other equipment entails a technical malfunction.
- Low quality connection of the linear part. The use of low-quality cables and loops is one of the main reasons why the volume sensor of alarm systems is triggered. Most often observed with manual twisting without the use of automated equipment. A malfunction may occur immediately or after several years of operation. Remediation often requires a complete replacement of working cables.
- Incorrect mounting systems. False alarms are often triggered due to defects in the fasteners of the supply systems and sensors. Any deviation from the design standards may lead to a violation of the functionality of the alarm and warning. The contact of linear systems with other communications often provokes interference, cable breakage and spontaneous shutdown of surveillance cameras.
- Electromagnetic exposure. A common cause of false alarms in a building. When installing smoke detectors, it is important to observe the recommended distance to operating electrical appliances and equipment that emits its own electromagnetic pulses. In the event of a problem, it is necessary to change the location of the security system nodes.
- Incorrect setting. Very often a false alarm of a fire alarm is observed due to improper equipment settings. In case of an error, the security system will create significant operational difficulties. All sensors must work properly. After all, the security of an individual object and the health of people depend on this.
The most correct solution to these problems is to appeal to highly qualified specialists who have experience in this field and the corresponding equipment for diagnosis. To avoid possible problems in the future, it is best to initially control the installation and selection of materials.
False alarms for fire alarms and security systems. External factors
External influences on the operation of security systems are no exception. Often there is a false response of the motion sensor in the actual absence of moving objects. There may be several reasons for this. Most often, devices are triggered due to improper installation near tree branches, shrubs and other ornamental plantings that sway with a strong wind. In this case, a response sensitivity setting is required. A more serious problem is considered when the motion sensor is triggered by the sun in the daytime.
The main reason for spontaneous switching is usually the presence of a significant voltage drop in the network. The motion sensor system is designed so that when power is applied, the device automatically enters the activity mode. Accordingly, with a sharp surge in voltage, self-operation occurs. An effective solution is to install a power leveling unit. Also to common reasons why the motion sensor itself turns on and off, the temperature mode of operation also applies. With a sharp change in temperature, the protection device can turn on spontaneously. This problem is eliminated by installing security equipment in a protective case above the door or in a place where there are no sudden temperature changes.
What to do if a fire alarm goes off?
Everyone already understood that there could be several situations when a fire alarm went off. The option when this is a training alert will not be considered today.
Actions when a fire alarm is triggered depend on the cause of the response. It is necessary to look at the sensor address on the dashboard and examine the area around to determine the reality of the threat. Depending on this, there will be two possible scenarios:
- False alarm.
- Turn off the siren.
- Find and eliminate the cause of the false alarm yourself or call the service company.
- Make an entry in the fire safety log.
- If you can put out the fire using improvised means, do it. Otherwise, follow these steps.
- Call the fire department at 01 or 112.
- Notify the fire safety officer at the facility.
- Notify people in the building and start the evacuation.
- On your way to a safe area, close the doors behind you and turn off the power. Also, if possible, capture valuable documents.
- Upon arrival of the rescue team, help them connect to the hydrant and report on the remaining people inside the building.
- Stay in a safe area and never come back.
How to disable a fire alarm?
Suppose the signal turned out to be false. Then you need to quickly turn off the siren, as according to statistics its sound is great on the nerves and annoying others.
Depending on the type of room, the alarm goes off differently:
- Apartment. Most often there are installed sensors on batteries, which are disabled by pressing a button on the case. If not, remove the battery. To do this, turn the case clockwise, remove it and remove the battery. Remember to turn it back on later.
- Multi-storey residential building. The entire fire complex is monitored by the UK home. The siren has turned on - look for a sign on the floors with the number of the person responsible for fire safety and inform him. If the concierge or the watchman sits below, then it is his duty to call and disconnect the siren.
- Budgetary, industrial and administrative organizations, and public buildings. There, a full-fledged alarm system is always installed, which is monitored by a guard from a special control room.
To disable the alarm using the dashboard, use the manufacturer's instructions or the technical data sheet. As an example, there may be indicated:
- press the alarm mute button several times or *,
- press #, dial the number of the triggered detector and press *,
- enter a personal code.
The fire alarm system, with the exception of apartments, is maintained by special companies. They need to call if a problem is detected. If monitoring is connected, they will call you within 30 seconds and ask about the need to call firefighters.
In cases where the signal is considered false, an installer is sent to you. After inspection, he will identify the cause of the operation and solve the problem.
It is also the responsibility of such companies to regularly inspect all fire fighting equipment, which may detect a problem before it develops.