Modular Burglar Alarm
The described circuit is designed for security applications, providing essential features for alarm systems. It incorporates automatic Exit and Entry delays, allowing users to exit or enter a secured area without triggering the alarm immediately. This is particularly useful in residential or commercial settings where users may need a brief period to deactivate the system upon entry or exit.
The timed Bell Cut-off feature ensures that alarms do not sound indefinitely, which can be critical for reducing nuisance alarms and maintaining a positive user experience. The circuit supports both normally-closed (NC) and normally-open (NO) contacts, providing versatility in sensor integration. This allows for the connection of a variety of sensors, such as door/window contacts, motion detectors, and other security devices, accommodating different installation requirements and preferences.
A notable feature is the 24-hour Personal Attack/Tamper zone, which remains active regardless of the system's armed status. This ensures that any unauthorized tampering or distress signals are immediately addressed, enhancing the security of the premises.
The circuit operates on a permanent connection to a 12-volt power supply, ensuring reliable operation. The activation of the circuit is controlled by a switch (SW1), which, when opened, enables the system. This design allows for straightforward installation and maintenance, as users can easily access the switch to enable or disable the system as needed.
Furthermore, the inclusion of expansion modules allows for scalability. Users can add multiple zones to the system, accommodating a variety of sensor types, including inertia (shock) sensors. This feature is particularly beneficial for larger areas requiring comprehensive coverage, as it allows for tailored security solutions based on specific needs and layouts.
Overall, this circuit design provides a robust framework for implementing an effective alarm system, combining user-friendly features with advanced security capabilities.This circuit features automatic Exit and Entry delays and a timed Bell Cut-off. It has provision for both normally-closed and normally-open contacts, and a 24-hour Personal Attack/Tamper zone. It is connected permanently to the 12-volt supply and its operation is "enabled" by opening SW1. By using the expansion modules, you can add as many zones as you require; some or all of which may be the inertia (shock) sensor type.
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