Purpose of having Car Alarm system installed

It urged to react to external event by a short notifying or long disturbing signal. Statement on protection and removal from it is carried out by means of the remote controls, steering with system on a radio channel, and is accompanied accordingly by lock-up and unlocking of door-locks. There are systems an optical (infra-red) communication channel much less often. The overwhelming majority of systems allows to remove system from protection by means of the latent or openly located coded switch. It happens it is useful in a number of extraordinary cases.

The event calling operation of system on protection, opening of a door, a cowl or a luggage compartment, crashed windows, blow, change of a discharge angle of a body, penetration into interior through the lowered glass can be.

Effects to which the system can react, are defined by its complete set. As a rule, the end cutout switch installed on a cowl or a luggage compartment and the transmitter of blow goes into a package. The input on which opening of doors is defined, is usually connected to the regular cutout switches already installed by the car. If the blow transmitter two-level at weak blow the system produces a warning signal in the form of a trill or a series of short sound signals, strong blow calls a panic cycle, as well as effect on any other safeguarded zone. Some models of signallings have function of the control of voltage of a board web and work at inclusion of any consumer of the electric power, for example, interior light lamps.

The radar transmitter reacting to approach to the car and penetration into interior, the ultrasonic transmitters also reacting to movement in interior and so on also can go into a package of security system and other transmitters, for example. If the desirable transmitter does not go into a package, it can be acquired in addition.

At operation the autosignalling executes an alert cycle (or a panic) at which the attention draws to the car acoustical and light signals. Light signals move with blinking marker light or turning movement signals, imitating an emergency stop signal. Sound signals move or a regular automobile horn, or a siren which is going into a package of security system.

The siren can have the firmware accumulator. Such sirens are called as autonomous. At miss of external power supply the disturbing signal is given. For prevention of a disturbing signal at accumulator cutting off, for example, at repair or service on the case of the majority of autonomous sirens there is a cutout switch combined with the lock under a tubular or flat key. Presence of an autonomous siren to some extent raises guard degree.

Except the disturbing notification, the autosignalling has function of interlock of the drive. The central block usually has one or two exits for connection of the external relay of interlock, or the firmware relay. There are the devices having one firmware relay and one exit for connection of the external relay. If exit two, they, as a rule, mutually inverse. One is intended for connection of the relay with normally closed contact pieces, another - with normally openloop. In some systems polarity of a unique exit is programmed at installation.

The interlock relay setting allows to augment time necessary for the car thief to start the drive.

Development of a functional set of the signalling is reduced to presence of additional control paths by various devices in different conditions and the various service functions programmed at installation, or while in service.

Some models of autosignallings have a starting engine operation subfunction. On the device they it is more difficult than signallings of the class approximately in 1,5 - 2 times. Steering of start function is made at the command of one of additional channels of a radio charm. Thus, not going out the house, it is possible to start the drive for warming up. Probably also presence of function of start on internal event, for example, on kickdown of temperature or after an interval between starts. More often such devices have no input of an external command that does impossible correctly to connect other sources of a command of start.