First Alert Wireless Interconnect Hardwired Smoke Alarm - SA521CN-3ST (1039830)
Wireless Interconnect Hardwired Smoke Alarm
The First Alert SA521CN-3ST Interconnected Smoke Alarm allows owners to create an interconnected fire alarm system without the cost and hassle of wiring. Use this smoke detector to replace an existing hardwired smoke alarm and then install additional First Alert Wireless alarms for an interconnected safety network (additional alarms sold separately). This hardwired smoke detector can connect and communicate with up to 18 compatible alarms, so when one alarm is triggered, the entire system reacts. An integrated battery backup ensures the smoke alarm continues to work even during power outages.
Photoelectric Sensor Warns of Smoldering Fires
The First Alert Wireless Interconnect Smoke Alarm comes equipped with a photoelectric sensor to provide the earliest possible warning of fire. The sensor is optimized to detect larger smoke particles produced by smoldering fires, such as those caused by unextinguished cigarettes. It also distinguishes between real threats and smoke/vapor produced during showering, cooking, and other everyday activities, helping minimize the number of false alarms. A patented smoke entry system helps ensures reliable detection by providing a direct air pathway to the sensor.
Interconnectivity for Larger Areas
The hardwired smoke alarm can be connected to other compatible BRK and First Alert hardwired alarms for larger buildings such as dormitories, office buildings, and apartments. Connect up to 18 compatible devices: up to 12 smoke alarms and 6 compatible devices like horns and repeaters. The communication distance (range) between any two First Alert Wireless Interconnect Alarms is typically 50 ft. (15 meters) inside of a home. Some features of a home, such as the number of floors, number/size of rooms, furniture and types of building materials used may reduce the range of wireless interconnect alarms. First Alert helps you create a comprehensive warning system for you and your property.
Battery Backup for Continuous Coverage
In the event of a power outage, the smoke alarm is still able to function thanks to its two AA backup batteries. An indicator sound is emitted when the batteries need to be replaced. The inclusion of an optional drawer and mounting bracket lock will discourage tampering.
Test and Silence Button
Mute Button has been included to serve the dual purpose of silencing nuisance alarms and testing the functionality of your alarm.
EZ-Access Battery Door
The addition of an EZ Access Battery Door removes the hassles and burdens associated with changing your alarm's batteries.
First Alert Wireless Interconnect Hardwired Smoke Alarm SA521CN-3ST
How to Install First Alert SA521CN-3ST Hardwired Smoke Alarms:
In this guide, we'll be showing you how to install First Alert Hardwired Smoke and Carbon Monoxide Alarms. Here are a few items you'll need before starting the installation process: Needle-nose pliers or utility knife, screwdriver, wire stripper, wire nuts and a ladder.
Hardwired Smoke or Carbon Monoxide Alarm Requirements:
- 120V household electrical circuit (unswitched 120VAC)
- Standard wiring junction box to a 4 in. (10 cm) size, on either the ceiling or wall
- Selecting an appropriate location to install your smoke and carbon monoxide alarms (see below guidelines for additional information):
- When installing an alarm on the wall, the top edge of an alarm should be placed between 4 in. (100 mm) and 12 in. (300 mm) from the wall/ceiling line.
- When installing an alarm on the ceiling, place the alarm as close to the center as possible.
- In either case, install the alarm at least 4 in. (100 mm) from where the wall and ceiling meet.
- First Alert Smoke Alarm FAQs
- First Alert Carbon Monoxide Alarm FAQs
Connecting First Alert Hardwired Alarms to 120V Wiring
To begin, turn off power at the junction box and connect your alarm to the building's electrical wiring.
- Locate the junction box and turn off power
- Remove the power connector from the new alarm's packaging
- Using wire nuts, attach the hot (black), neutral (white), and interconnect (orange) wires
|Attach to black wire on power connector
|Attach to white wire on power connector
Standalone (single-station) alarm: This wire is not needed; tuck the orange wire into the junction box.
Mounting First Alert Hardwired Alarms
- Secure the mounting bracket to the ceiling or wall using screws (included in the package)
- Insert the power connector into the plug on the back of your alarm
- Tuck any hanging wires into the junction box
- Position the base of the alarm onto the bracket and turn it clockwise until it's secured
- Remove the pull-tab to activate the backup battery
Installing Additional and/or Interconnecting First Alert Hardwired Alarms
If you are installing more smoke or carbon monoxide alarms, you'll want to repeat the process throughout the building. Interconnected smoke and co alarms must meet all requirements:
The same fuse or circuit breaker must power all interconnected alarms.
Up to 18 compatible detectors can interconnect, with a limit of 12 smoke alarms.
The total length of wire interconnecting the alarms should be less than 1,000 ft. (300 meters). This type of wire is commonly available at hardware and electrical supply stores.
All wiring must conform to all local electrical codes and NFPA 70 (NEC). Refer to NFPA 72, NFPA 101, and your local building code for more information.
Interconnect wiring diagram:
If you have any doubts or reservations about these interconnect requirements, please contact an experienced electrician to install your wiring and hardwired alarms.
Restoring Power and Testing Hardwired Alarms
Once you've installed your hardwired alarms, you'll want to restore power to the junction box. Under regular operation, the power indicator light on the alarm will shine/blink to indicate that it is receiving AC power.
Here's how you can test standalone or interconnected alarms:
Standalone Alarms: Press and hold the Test/Silence button until the unit triggers an alarm.
Interconnected Alarms: Press and hold the Test/Silence button until the first unit triggers an alarm. All interconnected detectors should sound off. Repeat this process to test each alarm in the interconnected series.
- Power Source: Hardwired
- Battery Backup: Two AA
- Sensor: Photoelectric
- Wireless Interconnect: Can be linked with up to 18 units (12 Smoke, 6 CO/Heat/Relay)
- Smart Sensing Technology: Helps reduce nuisance alarms
- Noise Output: 85 dB in a T3 Pattern
- Single Button: One press to silence and test alarm
- Easy Installation: Universal mounting bracket and plug-in power connector for hassle-free installation
- Tamper Resistant: Includes Locking Pins, Theft-Prevention Lock
- Dust Cover: Keeps alarm clean during construction
- Improved UV Resistance: Keeps alarm from discoloring over time
- Standards: UL 217, FCC Compliant
- Eco-Friendly: Completely recyclable as an electronic device
- Warranty: 10 Year Limited
- Product Dimensions (LxWxH): 5 x 2 x 5.in.
- Product Weight: 1 lb.
- Smoke particles of varying number and size are produced in all fires. For maximum protection, use both ionization and photoelectric sensing technologies. Ionization alarms are generally more sensitive to fast flaming fires and photoelectric alarms are generally more sensitive to smoldering fires.
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