Alarm Bell for Fire Protection, Schools, Security, & More!
*Bell Back Box Sold Separately*
These Alarm Bells are perfect for a variety of applications: fire alarms & sprinkler systems, pressure switches, schools, security, and more! As one of the loudest product lines of bells on the market, these bells are available in 120V AC (Alternating Current) and 24V DC (Direct Current) in 6 in., 8 in., and 10 in. gong diameters. The 24V Bells and 120V Bells have a rated current of 25 mA and 100mA, respectively. Each bell reaches 95dB at 1m, with the 24V DC Bells maintaining that level up 110 ft. and the 120V AC Bells maintaining up to 140 ft.
For reference – at 80 ft. these bells are still louder than the average garbage disposal if you were standing next to it. These bells are loud enough to be heard at great distances in most businesses, restaurants, schools, and other buildings. When paired with a Bell Back Box, these bells can be safely mounted and used outdoors.
Do I need a 24V DC or 120V AC Bell?
120V AC Bells:
Most users connect the 120V AC Bells to an electronic flow or pressure switch. As part of an NFPA 13 waterflow alarm, these bells encourage people nearby to call 911, and can even direct first responders to the location of inlets serving a building's fire sprinkler or standpipe system (FDCs). They serve as occupant notification devices, signals that facilitate evacuation.
In compliance with the 2019 edition of NFPA 13: Standard for the Installation of Sprinkler Systems, these alarm bells:
Are listed (7.7)
Can be provided with accessories for weatherproofing and impact protection required for outdoor bells (16.11.1.2)
Typically, one fire bell or other notification appliance is required at every system riser where water from an outside source enters a building's fire protection system. These waterflow alarms are required with every NFPA 13 system that has more than 20 sprinklers (16.11.2.1).
This alarm bell can also be used as part of an NFPA 72-compliant fire alarm system.
These high-voltage, 120-volt AC (120V AC) alarm bells are typically suitable when connecting to switches, waterflow sensors, or a building's power supply.
24V DC Bells:
Most users connect the 24V DC Bells to a fire alarm control panel, and serve as occupant notification devices that signal evacuation. In compliance with the 2016 edition of NFPA 72: National Fire Alarm and Signaling Code, these fire alarm bells are listed (18.3.1) and have a nameplate with their electrical requirements and select installation rules (18.3.2).
This UL-listed device is recommended for use in apartments, dormitories, and with other residential systems. It's estimated to cover the following distances in compliance with NFPA 72:
Public mode (notifying everyone in an area): 10 feet with average ambient levels of 80 dB - or 35 feet at 70db
Private mode (notifying staff tasked with evacuating a building's occupants): 10 feet with average ambient levels of 85dB - or 35 feet at average ambient levels of 75 dB
Sleeping area (waking sleeping residents): 10 feet with average ambient levels of 80 dB - or 35 feet at 70dB.
These low-voltage, direct current (DC) bells are typically suitable when connecting to a control panel or a transformer (a device, often found with doorbells, that reduces voltage).
