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The Underwriters Laboratories' UL 294 is a safety standard that addresses the construction, performance, and operation of access control systems intended to regulate or control entry into and exit from secured areas. These systems can also restrict access to certain devices through electrical, electronic, or mechanical means.
Wall-mounted electromagnetic door holder securing a door in the open position. An electromagnetic door holder (electromagnetic door holder and release or hold-open device, sometimes informally called a mag hold open or electric doorstop) is a simple electromechanical mechanism which can be used to hold a fire door or security door open until given a signal to release.
The EN 54 series of standards covers the following topics and product groups related to fire detection and fire alarm systems: [6] [7] Introduction: the introduction to the series of standards contains a diagram of a fire alarm system as well as numerous definitions of terms that are used in the other parts of the series of standards.
Remote alarm systems are used to connect the control unit to a predetermined monitor of some sort, and they are available in many different configurations. Advanced systems connect to a central station or first responder (e.g. police/fire/medical) via a direct phone wire, a cellular network, a radio network, or an IP path. In the case of a dual ...
In electronics, a remote control (also known as a remote or clicker [1]) is an electronic device used to operate another device from a distance, usually wirelessly. In consumer electronics, a remote control can be used to operate devices such as a television set, DVD player or other digital home media appliance. A remote control can allow ...
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A PLC is an industrial microprocessor-based controller with programmable memory used to store program instructions and various functions. [21] It consists of: A processor unit (CPU) which interprets inputs, executes the control program stored in memory and sends output signals, A power supply unit which converts AC voltage to DC,
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