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Battery Backup Unit (BBU) The ONT includes a Battery Back Unit (BBU) feature. You may utilize this feature by maintaining an active battery in the BBU. With an active battery, the BBU will provide backup power for your basic FiOS voice services, including Emergency 911 dialing, for up to 8 hours in the event of a commercial power failure. You are responsible for purchasing and/or replacing the battery in the BBU. Much like you would need to replace the batteries in a portable radio from time to time, periodically the BBU must be replaced. Please note that a damaged or leaking battery may damage Verizon network equipment and should be removed and/or replaced immediately.

Figure depicting the model types of the Battery Backup Unit Model types of the Battery Backup Unit

The BBU is installed at your location in an area where it can be easily monitored - most likely near the ONT Power Supply Unit (OPSU). The BBU is connected directly to the ONT to provide backup power if it's needed. In addition, the BBU contains a series of indicator lights that tell you whether your service is being powered by your location's electricity or the battery if one is intalled in the BBU.

The BBU also indicates when the backup battery needs to be replaced.  Click here for an explanation of the Battery Backup Unit (BBU) indicator lights. 

How do I get a replacement battery?
Verizon supplied batteries are under warranty for one year. How long you've had your battery generally determines when a replacement is needed. Follow the guidelines here.

The Battery Back-Up Unit is designed to use a 12-Volt 7.2 Ah SLA (Sealed Lead Acid) battery. Use of a different battery type is not recommended since other battery types may impact the performance of your FiOS services. Verizon is not responsible for damages which result from use of an improper battery. Batteries may be obtained at verizon.com/fiosaccessories or at a third party retail vendor.


How do I properly dispose of my old battery?
Battery disposal standards and requirements vary by state. If you need to replace the sealed lead-acid battery in your backup unit, please check with the following Environmental Protection Agency (EPA) resources for proper disposal instructions:


Visit www.epa.gov/osw  or call the EPA directly at 1-202-272-0167

See Also:

BBU Audible Alarms

BBU Indicator Lights


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