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FiOS Internet

How do I Order, Replace and Dispose of my Battery Backup Unit (BBU)

Your Fiber-Optic Voice service requires electricity in order to work. In the event of a power outage, you won’t be able to make or receive calls, including calls to 911, unless you use an alternative like a cell phone. If you have an alarm system it may not be able to contact its central monitoring station in the event of a power outage. Depending on the Verizon equipment installed at your business, backup power may be provided by a Battery Backup Unit (BBU) that uses a 12-volt battery or a PowerReserve device that uses 12 D-cell batteries that you provide. Please click on the picture below that matches the equipment installed in your business.
Battery Backup Unit (BBU)

Power Adapter and PowerReserve

How do I order, replace and dispose of the battery for my Battery Backup Unit (BBU)

Battery Backup Unit Closed
Battery Backup Unit Open
The Optical Network Terminal (ONT) includes a Battery Back Unit (BBU) option, which you may utilize by maintaining an active 12-volt battery in the BBU. With a fully-charged battery, the BBU will provide backup power for your basic Fiber-Optic 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 smoke detector or flashlight from time to time, periodically the battery must be replaced.

The BBU is installed at your location in an area where it can be easily monitored. 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 installed. The BBU also indicates when the 12-volt battery needs to be replaced.


Know your Battery Backup Unit
  1. Alarm Silence – Press to silence audible alarm.
  2. Battery Emergency Use – Press once to reboot the ONT and get up to 1 hour of battery life for emergency phone calls. Once pushed, all remaining battery life will be used.
  1. Auxiliary Power Source
    GREEN - Power Available
    RED - Power Not Available

  2. Replace Battery
    RED – battery needs to be replaced

  3. Battery Power
    RED – ONT is operating off battery power; no AC power available
    BLINKING RED – low battery power

  4. System Status
    GREEN – normal operation
    BLINKING GREEN – system fault

BBU Audible Alarms
If there is a problem with your BBU, an alarm will sound for 2 seconds and be silent for 58 seconds. This will be repeated until you press the Alarm Silence button. Once you do, be sure to check the lights on the BBU to find the issue (see above). Below are the most common reasons for the alarm to sound:
  • Low Battery – alarm is silenced after electrical power returns, the battery is fully discharged or removed from the BBU
  • Replace Battery – alarm is silenced when the battery is removed
How do I get a new or replacement battery?
Verizon provides free replacement batteries only if your battery was provided by Verizon and it is still under the one-year warranty period.

If you need to purchase a 12-volt battery for your BBU, you can do so at verizon.com/fiosaccessories or from a variety of retail locations.


My battery is no longer under warranty, how do I order a replacement
If your battery is under warranty, you can order a replacement battery by calling us at 1.800.VERIZON (1.800.837.4966). if your battery is no longer under warranty, you can order a replacement battery online.


My battery is no longer under warranty
The easiest way to purchase a replacement battery is to visit verizon.com/fiosaccessories. Batteries may also be purchased from a third party vendor; however, it must be a 12-volt 7.2Ah SLA (Sealed Lead Acid) battery. The use of other battery types is strongly discouraged since it may damage the equipment. Verizon is not responsible for any damages resulting from the use of an improper battery.


How do I install a new 12-volt battery?

You will receive instructions on how to install your battery when your new battery is delivered or you can watch the video instructions provided here.



IMPORTANT NOTE: Batteries need to be disposed of properly. Visit epa.gov/osw or call the EPA at 202.272.0167 for instructions


See Also:
Checking the Battery Back-up Unit



How do I setup and use my Verizon Power Adaptor and PowerReserve

Your Verizon FiOS voice service needs power to work. The type of Optical Network Terminal (ONT) you have is powered by a Power Adaptor. If you want back up power in case of a power outage, your ONT can be equipped with a Voice Backup PowerReserve device.



Power Adaptor
Image of Power Adaptor


What is a PowerReserve Device?
If your ONT is configured with a Power Adaptor, you may utilize the Verizon Voice Backup PowerReserve device which provides backup power for your basic voice services, including Emergency 911 dialing, for up to 20 hours in the event of a power failure. Please note that you may be responsible for purchasing the PowerReserve device and the initial set of 12 D-cell batteries, as well as being responsible for purchasing any replacement batteries.


The PowerReserve device can only be purchased from Verizon; however, D-cell batteries may be purchased from a variety of retailers.


PowerReserve Device
Image of PowerReserve Device


How do I install my PowerReserve Tray?
The PowerReserve device is easy to install and can be mounted on the wall, if desired. Please follow the Power Reserve Installation Instructions here (pdf format) or use the online instructions below.

How do I order a replacement PowerReserve Tray that is under warranty?
If your PowerReserve device is not functioning properly and it is still under warranty (within 1 year of purchase), you can order a replacement at no cost by calling us at 1.800.Verizon (1.800.837.4966).

How do I order a replacement PowerReserve Tray that is out of warranty?
If your PowerReserve device is not functioning properly or has been damaged and it is out of warranty, you may purchase a replacement by calling us at 1.800.Verizon (1.800.837.4966).

I have other FiOS services, can I get a PowerReserve?
The PowerReserve device will only power fiber voice services, and is only available for use with certain types of Verizon equipment.

How do I know if my batteries are working?
Using the Battery Test strip included with your PowerReserve device, remove and test each battery and replace any batteries that failed the test.

Where do I get new batteries?
You are responsible for purchasing any replacement batteries which are available a wide variety of retail and/or home improvement stores.

How to install PowerReserve device
(You can download these instructions in pdf format here.)

  1. Power Reserve Case OpenedOpen the PowerReserve door by pressing the latched tab toward the unit and then pushing the tab up.

  2. The PowerReserve device can be laid flat or mounted to a wall.

  3. Uncoil the cable located in the center of the tray.

  4. Power Reserve Case Switch and wire coilInsert 12 new D-cell alkaline batteries into the device. DO NOT use rechargeable or Lithium batteries.

  5. Place the power switch to the OFF position.

  6. Plug the power cable into the power adapter.

  7. Close the PowerReerve door.

  8. Leave the unit OFF until needed during a commercial power outage.

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