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In its simplest form, the user activates the alarm by pulling the handle down, which completes a circuit and locks the handle in the activated position, sending an alarm to the fire alarm control panel. After operation, most fire alarm pull stations must be restored to the ready position using a special tool or key for the panel to be reset.
Exterior alarm bell box. If a potential intruder tries to enter into a house, they test whether it is closed and locked, uses tools on openings, or/and applies pressure, creating low-frequency sound vibrations. Before the intruder breaks in, the infrasound detector automatically detects the intruder's actions.
Single point or multipoint alarm logic modules operate the window lights based on a preselected ISA 18.1 or custom sequence. In one common alarm sequence, the light in a window will flash and a bell or horn will sound to attract the operator's attention when the alarm condition is detected.
When the box is activated by turning a knob or pulling a hook, a spring-loaded wheel turns, tapping out a pulsed electrical signal corresponding to the box's number. [1] A receiver at fire headquarters announces the alarm through flashing lights or tones, or via a pen recorder, and the box number is matched to a list of box locations.
A fire alarm notification appliance is an active fire protection component of a fire alarm system. A notification appliance may use audible, visible, or other stimuli to alert the occupants of a fire or other emergency condition requiring action. Audible appliances have been in use longer than any other method of notification.
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Coded fire alarm pull station below a 10-inch (25 cm) bell. Magnetic smoke door holders and retainers are wall-mounted solenoids or electromagnets controlled by a fire alarm system or detection component that magnetically secures spring-loaded self-closing smoke-tight doors in the open position.
The housing of the bell box may be manufactured from wood, metal, or plastic. The basic core component of a conventional bell box is an electromagnet and a bell or other metal piece, some of which create a repetitive sound. [1] The bell sound is normally created inside the box, although the unit may have bells mounted on the outside of the box.