Description and types of volume sensors for alarms, how to select and connect

Scope of application and operating principle

The mechanisms are installed in cars; they are also installed in enterprises, private homes, and cottages. Often devices react to random interference or false contacts. To ensure that shock sensors only recognize real dangers, they are equipped with dual-zone monitoring. Even a slight blow causes the car alarm to go off.

If a strong and powerful shock occurs, for example, during an accident, a break-in, or breaking glass, an alarm will sound. It will function according to an established pattern with a certain time range. It is to recognize different types of impacts that a two-zone system has been developed.

Also, to correctly recognize impacts, the device has a sensitivity element that reacts to force and is transformed into a signal.

The vehicle airbag sensor turns on when a vehicle collision occurs. Previously, there were few airbags, so frontal products were introduced to increase safety in frontal impacts. Nowadays, many cars have side airbags installed, so the number of devices has increased.

The functioning of the mechanism is that in the event of an accident, only the necessary airbags are deployed. To do this, it is necessary to calculate the force of the impact and establish its trajectory. This is done by sensors mounted in different parts of the car - doors, pillars.

Review of popular models

Echo -5

Security sensor used in both centralized security systems and local alarm systems. Ultrasonic device for detecting the movement of an intruder in a protected area.

Features and Specifications:

• System control of external effects of radiation overlap;
• Automatic performance check system;
• Adjusting the sensitivity level during setup;
• The maximum volume of the guaranteed control zone is 250 m2;
• Range - 10 meters;
• The speed of the object to trigger the device is 0.3-2 m/s;
• Degree of protection IP 30;
• Dimensions 150x45x25 mm;
• Weight – 75 g;

Argus -3

Radio wave volumetric detector. Designed for operation in heated and unheated premises as part of centralized and local security systems. It is distinguished by high reliability and reliability of detecting violations of the protected area. Use with similar devices in the same room is allowed.

Features and Specifications:

• Minimum range – 2-3 m;
• Operating temperature - -30 +50 degrees Celsius;
• Guaranteed detection area – 20 m2;
• Weight – 100 gr.

PYRONIX COLT QUAD P1

Passive infrared sensor. Used for installation in centralized and local security systems. The peculiarity of the design is the possibility of use in enclosed spaces with forced ventilation. Masking is allowed with materials that do not interfere with the propagation of radio waves - fabric, wooden gratings. The device has a high degree of protection against natural and artificial interference. Does not react to animals weighing up to 27 kg.

Features and characteristics of the device:

• The intruder detection zone is 10 m with a horizontal viewing angle of 90 degrees;
• Housing type – sealed;
• The case is protected from static voltage;
• Ambient temperature from -30 to +70 degrees Celsius;
• Dimensions – 75x52x44;

Sensor settings

If the device is not installed correctly, the vehicle will respond to false impacts or not respond to real impacts. If the device does not respond to real dangers, then this is fraught with negative consequences. To set up the device, you can contact the Moscow service center, or make the connection yourself.

The shock and alarm sensor needs to be adjusted if the alarm is sensitive and reacts to passing cars or thunderstorms. The opposite happens - the mechanism does not notice strong impacts.

Users are interested in how to adjust the sensitivity element. First you need to find where the sensor is located. It is usually installed under the dashboard. If the owner cannot find it, you should ask a specialist for help.

To change the parameter of an element, there are adjusting screws on the device; we use them to adjust the device. To understand what level they correspond to, indicator lights are located opposite them. If you hit the sensor, the first level signal will work, that is, the green button will turn on. If the impact is stronger, the red indicator will turn on.

The screws are marked with adjustment signs “+” and “-”. The marking specifies the direction of rotation of the part. If you turn it clockwise, the sensitivity increases. The shock sensor is adjusted using this screw and is easy to adjust.

Installation and connection features

For each device, the manufacturer must indicate in the operating instructions the critical points for installing and connecting the device.

The following installation options are standard for internal sensors:

• ceiling option;
• dome installation option;
• installation in the corner of the room;

When choosing an installation location, the following are taken into account:

• technical characteristics of the sensor;
• frontal and horizontal angles of the sensor working area;
• linear dimensions of the room, placement of door and window openings;
• factors affecting the operation of the device - elevation angle above the surface, dust and gas contamination of the room, temperature conditions;
• specifics of the security object - open or hidden installation of devices;
• protection of the installation point from third-party influences.

In addition, during installation it is necessary to calculate the route of laying cable lines, the installation location of the wireless communication module and the power source for the sensor.

False sensor alarm

Often the shock and alarm sensors trigger falsely, which is due to an incorrectly configured system. You can correct shortcomings and errors yourself if you adhere to the recommendations and follow the rules.

Another reason why the indicator came on and the mechanism worked is that the platform was not fastened correctly. Plastic is often used as the main fastener, so it is easily deformed under impacts or under the influence of high temperature. To prevent false alarms, change the mount to a metal one.

Drivers often talk about the alarm going off during fog, rain, or snow. The key fob indicates that there was a knock on the door. There is a simple explanation for this - moisture got into the circuit, which caused a short circuit. To get rid of the problem, you need to find out in which of the locks the water triggered the sensor, and then simply isolate it from the penetration of condensate.

Also, various types of malfunctions are caused by the use of low-quality mechanisms. The device can be tested: in the settings, reduce the sensitivity value to the minimum lower threshold. Usually, the upper threshold of the signal will still be triggered; such devices are replaced in working order.

Criterias of choice

Weather resistance

According to safety requirements, the housing must provide protection of electronic components from dust and solid particles of at least level 4 protection. Protection against moisture penetration is calculated at less than level 6.

For home use, it is enough to have devices that meet the IP44 and IP54 protection levels, which provides protection from dust and splashing water.

Reaction to external factors

Active detectors must be protected from electromagnetic radiation; for passive detectors, the reliability criterion is the protection factor relative to the reaction to pets.

Purpose

All types of devices are applicable for internal production and warehouse premises; for premises in which personnel may be present, the exception is ultrasonic sensors.

Appearance

Devices are selected for open or hidden installation. Open placement should provide an aesthetic appearance, and with hidden installation, compact housing and cable lines.

Errors when installing the sensor

Sometimes errors occur when installing the mechanism, namely:

1. The shock sensor is useful in cases where the design of the sensor and communication module is damaged. Such problems arise due to damage or prolonged operation of protective mechanisms. The sensor and module loops are sometimes located close to each other; they will intercept radio waves and provoke the production of a signal. In this case, the distance between them is slightly lengthened.
2. Fragile fastening, made hastily using adhesive tape, or when the sensor is suspended on wires.
3. The sensor has expired. Any mechanism does not last forever, so the product must be replaced.

Drivers shared their own observations: false activation of the sensor occurs when a smartphone with ICQ enabled is left in the car. As soon as you turn it off, the signal stops immediately.

Alarm device

Home / Alarm device Let's figure out what the vast majority of car alarms that can be found on the security systems market consist of. The figure schematically shows the main elements of such a system. Let's consider the purpose of each of them.

Central block

The heart of a car security system is the central unit . No system can operate without an electronic control unit with a central processor. This device receives encoded signals sent by the remote control - key fob. It's that cute little button device that drivers carry on their car key ring. We will return to it below.

So, this central unit controls the operation of the alarm system - it receives information from sensors, analyzes it and sends signals to actuators and signaling devices, informs the owner about problems in the system, open doors, headlights not turned off, etc. The central unit has a hard memory, and even when the power is turned off, it remembers the program settings and code combination data received from the key fob.

In terms of design, car alarms can be implemented either in a monoblock design, that is, the central unit with a siren and one of the sensors are assembled in one housing, or in a spaced one - such as in the figure. European manufacturers often prefer a monoblock layout.

System power System is of great importance , that is, the voltage (its value and fluctuations) that is supplied to the central unit. A car, especially a modern one, is a complex system. It contains a huge number of energy consumers, blocks and wires. At different operating modes of the vehicle, voltage fluctuations and sags occur in the electrical circuit. A lot depends on how the alarm system is installed (how competently the installer supplied power to it), how the central unit and the system memory perceive these vibrations. There are many subtle points in this problem, but the car owner does not need to know them - it’s all on the installer’s conscience.

Keychain

The alarm system is controlled, most often, using a remote control - key fob . It transmits the car owner’s commands to the central unit, which, using an antenna, receives and decrypts the radio signal. The key fob is a miniature remote control radio transmitter. In order to prevent the alarm from being turned off by unauthorized persons, the key fob sends encoded radio signals. The level of secrecy, types of codes, and the number of their combinations in different alarm systems are different.

The key fob is equipped with one or more control buttons, pressing which generates a particular signal. If this signal belongs to the owner of the car, the car alarm normally responds to control signals and turns the alarm on or off and controls the unlocking or locking of doors, as well as many of its other functions.

The design of the keychain is constantly being improved. Many manufacturing companies pay great attention to the appearance - the design of the key fob.

The energy source for the remote control is 12 V batteries. Such batteries are now sold in any underground passage. The range of the key fob, that is, the maximum distance from which you can, for example, disarm or arm a car, is different for each system. Most often, this distance ranges from 30 to 50 meters. More accurate information can only be obtained from the technical manuals supplied with the specific car alarm.

In addition to the traditional key fob, the security system can be controlled from a transponder - a plastic card (resembling a driver's license coupon) or a small key fob containing highly complex electronic components. The transponder does not require power. There is no need to press buttons. All you have to do is get into the car and ensure that the card or key fob falls within the antenna’s field of action and the system will cancel the car’s security mode.

Sensors

The most important part of any car alarm system are sensors . Any car alarm system contains them. These are the original eyes and ears of the system. During any impact on the car, they provide information to the central unit about the degree of danger of the impact and its time. Considering that these impacts can be very diverse, sensors must ensure high reliability and reliability of the monitored parameters, leaving out everything that can be attributed to false disturbances: vibrations and oscillations from a heavy vehicle passing nearby, the impact of climatic and atmospheric phenomena, electromagnetic interference .

Car alarms use a variety of sensors that operate on different principles, and each of them protects the car from a particular danger. From impact, from opening doors, windows, from touching the car, from entering the interior. It happens that a thief suddenly doesn’t need the entire car, but only a chrome bumper or wheel caps. Each sensor must inform the alarm system about the plans of criminals or naughty teenagers.

The very first sensor that security systems began to be equipped with at the dawn of their appearance were “ heave sensors” . They reacted to the rocking of the car body, which could occur when the wheels were removed or another similar impact. I rocked the car and the alarm went off. The boys often brought car owners to nervous stress, especially considering the increased sensitivity of these sensors. However, if an attacker broke the glass, then most often the alarm was silent.

Gradually, “pitch” sensors replaced shock sensors (shock sensors). They reacted somewhat worse to the rocking of the car, but, on the other hand, they very clearly tracked impacts on the body. It has become almost impossible to break glass with impunity. And if a housemate, not very carefully maneuvering around your car, accidentally hits your bumper with his bumper, the alarm will immediately notify the entire yard about this, drawing everyone’s attention to the culprit of the “mini-accident.”

The first shock sensors had only one sensitivity threshold. This sensor is not very convenient. Either its setting was very coarse so that the car alarm would not be triggered by a ball accidentally hitting the wheel, and then there was a chance of missing a more important intrusion, or the sensitivity was set very high, in the hope of keeping track of every more or less small impact on the car, and the alarm was accompanied by a prolonged howl of the siren every dog ​​that passes by.

Two-threshold shock sensors do not have all of the above disadvantages . In such a sensor, the force of influence at which the first threshold and the second threshold will operate is separately adjusted. If a passer-by accidentally leans on your car, the system will simply warn the uninvited guest with a brief beep of the siren that he has invaded someone else's property. But if someone tries to break the glass or tear off the emblem from your hood, the car alarm will announce the presence of an enemy near the car with the sound of a siren.

Ultrasonic sensor . Or as it is also called ultrasonic. Its task is to detect the thief if he managed to get into the salon. Two remote microphones constantly monitor the interior in security mode. This highly sensitive sensor consists of an ultrasonic wave emitter that sends a signal and a receiver that receives this signal. If the received signal is interrupted or distorted, the alarm is triggered. Any body of sufficiently large volume moving in the cabin will be immediately detected and the alarm system will raise the alarm. However, its sensitivity is such that it is able to detect air movement in the cabin caused by temperature changes when the car cools down in winter and even acoustic noise. The disadvantage of these sensors is false alarms due to sudden temperature fluctuations and strong external sound vibrations.

The microwave sensor does not have all the disadvantages of ultrasonics . It was invented and used to protect open cars - convertibles. The operating principle is as follows. The sensor covers the car with two fields. The first field can also end outside the car body (at a distance of 20 - 15 cm). This is the first threshold. The second field takes control of the car interior. This is the second threshold. If a person comes too close to the car and crosses the first field, then, as in the case of the shock sensor, the system will warn the ill-wisher by beeping the siren. If the thief gets inside the car, he will be in the range of the second field, and then the system will raise the alarm. No matter how carefully the thief behaves inside the cabin, the microwave sensor will still detect him. Both fields can be adjusted up or down depending on the wishes of the car owner and operating conditions.

Voltage drop sensors. There is a formula for theft when a car battery is punctured, and when all the electrolyte has flowed out of it, the thief can calmly disarm the de-energized alarm. In many cars, the layout of the units under the hood is designed in such a way that you can simply bite the wires coming from the battery. To ensure that this fact does not go unnoticed, such sensors exist. They come in two main types. The first type of sensor is triggered when the voltage drops below a threshold preset at the factory (for example, 8 Volts). The second type of sensor is triggered when the voltage jumps down by a specified amount (for example, 1 Volt). Such a sensor will react even if the thief opens the door, the interior light comes on, and a slight voltage drop occurs, which is immediately registered.

Glass break sensor . It is used quite rarely in modern systems. Reacts to the sound of breaking glass (the microphone is specially tuned to this frequency). A properly configured shock sensor will replace the glass break sensor almost completely.

Contact type sensors (limit sensors). These are ordinary buttons that control the status of the doors, hood and trunk. Most often, standard car buttons are used. The hood and trunk are equipped with buttons when installing a security system. Modern systems have separate inputs for connecting limit sensors. This is done so that, firstly, when opening the hood or trunk, the interior lighting does not come on, and secondly, so that in alarms that have a trigger memory, it is clear why exactly the system raised the alarm. Since the car buttons, both standard and installed additionally, are in the zone of influence of the active environment - dirt, salt, water, electrolyte, they require careful care. This is one of the few preventive measures that can be performed by the car owner or in any car service center.

Moreover, developed alarm systems with self-testing in the event of problems in the limit switch circuit will turn off this sensor completely until the problem is resolved. The car alarm, of course, will tell its owner about a malfunction, but he may not hear this hint, or even ignore it altogether. Such an owner puts his car at serious risk.

LED Usually made in the form of a red light bulb, which is installed in a visible place. An LED has many responsibilities. The simplest and most common function is to signal that the car is armed. This is usually flashing mode. The LED can warn about malfunctions of the alarm system sensors, which sensors were triggered in the absence of the car owner. In some systems, the LED will signal for several days that another key fob has been recorded in the system memory. This can happen at a car service center where you take your car for repairs. There, another key fob can be programmed into the memory of your security alarm, so that they can then disarm the car and steal it.

Siren It is a “bell” that emits a sound signal with a power of up to 135 dB. The tasks of a siren are varied. Firstly, it turns on during an alarm, but for no more than 45 seconds, which corresponds to the European standard.

Secondly, it emits sound signals when arming and disarming the car. These signals can be turned off if necessary using the remote control if the car owner does not want to disturb the residents of his house at night. Third, it provides short-term warning signals when the first threshold of the microwave or shock sensor is triggered.

Light indication Different installers implement this function in different ways. You can make it so that in alarm mode the car will blink its dimensions, or you can use emergency signals. It depends on the commitment of the master and the needs of the owner of the car. I recommend using an emergency signal as a warning light. In this case, the owner standing to the side of the car at the time of arming and disarming will clearly see whether his car is armed or not (especially if he uses silent arming).

Why does the shock sensor light up?

There are several reasons why the light is on and the sensor is triggered:

1. Violation of the integrity of the airbags. Because of this, the control element does not receive impulses from the belts, controller and other components of the system.
2. Poor connection of electrical network mechanisms or lack of contact. If the connectors are poorly connected, this will cause the alarm indicator to light up. It is recommended to check the quality of the components and the integrity of the contacts.
3. Poor contact in the doors. When a car is repaired, the doors are removed so as not to interfere with the work, or they are replaced with new ones, then after installation you need to carefully check all the contacts.
4. The shock sensor lights up due to damage or breakdown of the controller. They can be poorly connected, so it is recommended to double-check the quality of installation and the condition of the connectors.
5. If the button is still lit after reconnecting the device, this indicates that the control unit memory urgently needs to be reset,
6. Failure or wear of safety devices also causes the impact indicator to light up.
7. Violation of the integrity of the wiring when replacing seats and control panels.
8. The error appears due to improper functioning of the steering wheel or its replacement. If the contacts are damaged after the procedure, the light will remain on continuously.
9. The airbag life has expired. Typically, PBs last for 10 years.
10. The voltage in the vehicle's on-board network has decreased. First, check the condition of the battery and generator.

Types of Pandora alarm sensors

It is the sensors that are part of the anti-theft alarms that ensure the effective operation of the security system as a whole. These devices allow you to monitor the presence or absence of factors of penetration into a protected object, or transmit information about its damage.

The main types of sensors that Pandora car alarm models contain:

• Shock sensor. Its operation is based on the ability to detect vibration levels on the car body that exceed the standards established during setup;
• Motion Sensor. The sensor is triggered when an attempt is made to steal a car or place it on a tow truck;
• Tilt sensor. Reacts to changes in the position of the vehicle body;
• Volume sensor. It is used to protect the car interior, as well as the perimeter of the body, and reacts to the presence of movement;
• Temperature sensor. Depending on the model, it shows changes in engine temperature or air in the cabin;
• Sensors for opening any of the doors, hood or trunk. Triggered when there is unauthorized access.
• Network voltage change sensor. Signals a change in the voltage of the car's on-board network.

Finding the Shock Sensor

The location of the mechanism depends on the brand of the particular machine. Most often the device is located:

• in the car interior;
• sometimes in the engine department;
• in the gasoline compartment.

The last option is typical for modern foreign cars. If you install an additional device, this causes a number of problems. In the event of a minor collision, the airbags did not open, but the vehicle cannot be started until the sensor is activated.

The airbag and impact sensor is an indispensable component of the system that ensures the safety of the driver and passengers. If it is broken, then in the event of a collision the airbags simply will not work. It is recommended to regularly check the device in order to carry out repairs and eliminate damage in advance. People's lives and health depend on this.

What types of detectors are there?

There are three main types of sensor:

• sound;
• microwave;
• infrared.

And one more additional type - combined. It is capable of combining several basic types, up to all three. And it is a more accurate and at the same time more expensive device.

All main types have their own pros and cons. Sonic has a small radius of operation; in some cases, animals or sensitive people can pick up ultrasound. In general, the effect of ultrasound on humans has not been fully studied, and opinions about its harm are divided into two camps.

Some believe that it is definitely harmful, others say the opposite. One way or another, the choice of an ultrasound device is an independent decision for each individual person.

The microwave device is quite clear in this regard. There is harm from it, and that’s absolutely certain. To minimize harm, manufacturers try to reduce its power in order to minimize the influence of microwave rays down to almost complete absence of influence.

However, “almost complete” and “complete” are two big differences. However, microwave devices are the most expensive and accurate of all.

Infrared devices are the only completely harmless devices. However, they are quite easy to deceive if used as a signal. At the same time, as a household appliance that works to automatically connect any system, it is ideal.

It is used in most modern household systems for turning on light, ventilation, heat and water. This is due, among other things, to its lowest cost compared to other types.