An alarm device or system of alarm devices gives an audible, visual, or other form of alarm signal about a problem or condition. Alarm devices are often outfitted with a siren.
Alarm systems include:
Burglar alarms, designed to warn of burglaries; this is often a silent alarm: the police or guards are warned without indication to the burglar.
is an electronic fire-protection device that automatically senses the presence of smoke, as a key indication of fire, and sounds a warning to building occupants.
Commercial and industrial smoke detectors issue a signal to a fire alarm control panel as part of a building’s central fire alarm system. Household smoke detectors, or smoke alarms, issue an audible and/or visual alarm locally from the detector itself. They can be battery-powered single units or several interlinked hardwired (mains-powered) devices backed up by batteries. The latter must be installed in all new buildings and after major refurbishments.
Motion Detector keeps an eye on the inside of your home. Use it as part of the alarm system when you leave the house. It detects movements reliably and precisely, instantly sounds an alarm and warns you immediately if unwanted guests try to gain access to your living spaces..