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FIOS when electricity is off

FIOS when electricity is off

Gold Contributor VII
Gold Contributor VII
Posts: 4,772
Registered: ‎10-18-2016
Message 11 of 15

@cjjjjj wrote:

Sorry, how do you determine if the backup is working, or if it was even installed? This is a new service, and there were no instructions provided

Call 1-800-VERIZON they can pull up your records. Or you can look at the ont that is either inside your house (usually the basement) or if outside it’s on your home you will see where the cabling is plugged into. The ont has to have power to make a connection to Verizon. If inside you will see a black brick type device that holds the batteries and then plugs into the electrical outlet. 


If old model ONT the battery is located either inside the box or pretty near to it.

calling is the best bet if you are in doubt.

Nickel Contributor
Nickel Contributor
Posts: 31
Registered: ‎04-29-2012
Message 12 of 15

Thank you, that was a great answer...it didn't occur to me to call Verizon. So I found out that the old answer, that you have FIOS for 8 hours after the electricity goes out is obsolete. Now you lose phone service immediately unless you buy an external backup. However, my question now is how you install the backup battery. The tech quy on the phone didnt know. He kept telling me that there was a door where you installed a battery, and there isn't. Does anyone know how to install it? My ONT type is I-211M-L. It's a black box about 3"x6"x1". Do you disconnect the wire that comes from the smaller power box and attach the external battery there?

I keep asking because I am elderly and have a family member with a health issue, so in a blackout we might need to be able to call 911. At this point, i am wondering why we need a FIOS phone!

Gold Contributor VII
Gold Contributor VII
Posts: 4,772
Registered: ‎10-18-2016
Message 13 of 15

I am also elderly...however it’s not as difficult as it may sound.

first off you want to buy an APC like from this link.




They vary in price, so you buy the one that gives the longest period of service.

then where the ONT is plugged into the wall (yes the ont has to be plugged into a 110 outlet) you first unbox the APC  power unit, and the plug it into your homes power.

then you unplug the ont from the power outlet and plug it into the APC power reserve 

unit. Now when your power goes out it kicks in and keeps the ont and phone service from losing power. You must remember if you are using any powered phone there must be a power unit for that as well.


you could install this yourself but if uncertain have a tech savvy kid or adult install it for you. Or go to http://www.apc.com/us/en/ and there are installation videos and instructions 

Gold Contributor V Gold Contributor V
Gold Contributor V
Posts: 1,213
Registered: ‎06-24-2018
Message 14 of 15

This picture should help there is a small input on the power supply where the D cell backup plugs into. Its number 6 on picture. 

Copper Contributor Terps
Copper Contributor
Posts: 12
Registered: ‎08-01-2019
Message 15 of 15

You need a backup power supply for your ONT and you need a backup power supply for your router and laptop/desktop computer.

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