Alarm Devices
Alarm devices produce audible, visual or other types of alerts to inform people that something needs attention. Early examples were bells, drums and other musical instruments, whistles on locomotives and ships, and klaxons. Modern alarm devices use electronic sensors that detect movement or other anomalies and generate alarms according to pre-set parameters. The signals may be sent to a central monitoring station or directly to an individual user. Some systems offer a remote mobile application that allows individuals to arm and disarm the premises or check system status.
Many systems also feature a control panel, which manages security system operation and programming. It receives signals from each sensor and monitors the premises for activity, sounds the alarm when a zone is breached and sends the information to a central monitoring station or first responder (police, fire, medical).
Sensors are placed in various locations around the building, including doors, windows and walls. They are activated by movement or other conditions that are considered suspicious, such as vibrations or breaking glass. The sensors are wired to the alarm panel. Some sensors are unidirectional and transmit only commands to the panel; others are bidirectional and can receive feedback from the panel as well.
Each sensor is associated with a specific zone in the building, and the software used by an alarm system determines how each trigger will be interpreted. lone worker safety solutions Typical alarm triggers include motion sensors, door and window contacts, smoke and heat detectors, acoustic breakage detection devices and flood sensors. In addition to the sensors, a control panel can also include indoor and outdoor sounders that emit sirens or flashing lights to scare off intruders.
To help prevent false alarms, some sensors have technology that measures the size of an object or its speed to decide whether to generate a signal or not. This helps to reduce the number of false alarms caused by insects, pets and small disturbances. Newer systems use intelligent electronics that are able to tune the sensitivity of the sensors so they only notify a central monitoring station when an alarm is generated by a true intrusion event, and not by minor disturbances such as wind or sunlight on the sensor.
Some alarm devices, such as horns or strobe lights, require the presence of an individual to turn them off. Others are automated and can be turned off via a mobile app or a user code, such as a key fob or smartphone. Some systems even allow caregivers to monitor the location of an elderly or disabled person, enabling them to see where the person is on demand.
While digital interfaces have their place in industrial applications, analog buttons and knobs still have some advantages. They are rugged, easy to understand and can be easily operated by gloved hands. They’re especially useful in environments where touchscreen operations aren’t practical or when human-machine interaction is required for complex machinery. We asked our panel of experts to share their insights on these time-tested devices and why they continue to have value.
