I currently still have one copper line at my house, along with FiOS voice/TV/Internet.
I'm holding onto it as long as possible; I'm near the shore, and there are periodic blackouts, during which the FiOS line is useless but the copper works just fine.
If I eventually have to convert over--Verizon won't fix copper lines in my area--I'm wondering about the battery backup. There's no place to put a second one. Does a second line get connected to the existing battery backup, and does having a second line effect the already crappy amount of power-out usage?
Most ONTs are capable of handling two phone lines. You can easily tell by opening the user access panel. If you see two or more "TEL LINE" connections, you've got one that will support two lines. I've never seen a one line ONT, so I expect you'll find two or more lines.
No additional equipment will be installed. Verizon will activate the second phone line remotely. If you're comfortable connecting the wires yourself, no Verizon technician will need to visit your home.
Backup power for all active phone lines comes from the same battery. Standby backup power isn't much different for one line vs. two lines. The big power consumption occurs when phones ring and when phone calls are active. If both phone lines are active at the same time the battery won't last as long. If you only use one line at a time I'd expect little reduction in standby time.
You can augment the battery backup with several methods. Some models of BBU (battery backup unit) have an "AUX" power connection. This can be connected to an external battery, such as a marine deep-cycle unit. It does not charge the external battery so you'd have to install a charger, too.
I plug my BBU into a small UPS. While not as efficient as using an external battery, it has the benefit of simplicity and of keeping FiOS TV and Internet services up until the UPS battery drains. I also have my router on the UPS so I can use my battery equipped Internet devices during power outages. If I lived in an area with frequent longer outages, I'd consider buying a bigger UPS.
If you install a back-up generator, you could also power the BBU and other network equipment from it.
Bottom line, you don't have to settle for the 8-hour standby time provided by the BBU's battery. You can supplement it any of a number of ways that make sense for your situation and budget.
Periodically--every 18 months or so--we get a hurricane or a nor'easter and the like, and power goes out for up to a week or so (post Hurricane Sandy, it was out for about 3 weeks). Those times, the copper landline works just fine. I don't think there's any realistic battery backup for such a thng, and with storm surges, an outside backup generator could get flooded, too, unless I build a structure on the side of the house to raise it half a story or more.
So, I've been doing self-repair on the second line, since Verizon has pretty much abandonded us on copper.
It's your call how to manage backup with FiOS.
Copper has problems, too. The big one being the maintenance needed on the outside plant is much more expensive then fiber. Water does all sorts of nasty stuff to copper. Salt water is even worse. Fiber just doesn't care about getting wet. Since water always wins, you can expect more problems with copper over time than fiber. The only way to win the war with water on copper is with regular preventative maintenance. You already know where that is going.
Some copper installations have powered equipment in the field. That equipment is often very susceptible to power and water damage. If it fails, no amount of CO generator power will keep it working. I've had several cases where storms caused Verizon's copper equipment to fail for weeks while fiber and Comcast stayed up. Copper isn't as great as it used to be.
Another backup for fixed phone service is a cell phone. With FiOS Digital Voice is is very easy to have your calls ring on both the home phone and a cell phone of your choosing. This is independent of power at the premise. If cell service stays up during the extended power outages, that may be an option for you.
If you have a system to keep refrigeration and heating powered during extended outages, powering a FiOS ONT would be a very small addition to that backup system. If you're living out of coolers and using blankets, then a cell phone recharged from a car may not be a bad temporary solution.
As mentioned before, some models of BBU allow an external battery to be connected. You could buy two deep cycle marine batteries and keep them charged for emergencies. When the power goes out, plug one into the BBU. Swap it when it dies and recharge it from your car or somewhere else. I'd expect a marine battery to provide several days of backup, so this might be a workable solution for you.
Bottom line, you can complain about the changes in backup power that FiOS makes us deal with, or you can investigate your options and find a method that works for you and your budget.
And yet, Hurricane Sandy destroyed the FiOS NID (the various connections inside it for the house are all metal), but the copper kept working. Had phone service working right after Sandy with the copper, but nothing with FiOS for almost four weeks-- Verizon refused to come do the repair until full grid/house power was restored. They did not consider generator power acceptable. In the past 8 years, the fiber NID has had to be fixed twice due to corrosion--each time it was bad enough that Verizon had to be called--but the copper box just once, and I was able to do that myself.
I started to respond to the different points, but stopped because the response was getting so long; in short, believe me, I wouldn't be wasting time posting all this if the answers were so simple. Without going into details: I've been through all that over the years and for various reasons the solutions didn't work, which is why I've been keeping at least one copper line. I've had both Digital Voice (and FiOS Voice before that) and copper for years, and it's been my personal experience that the copper line has been much more dependable over that time. I'd rather keep both so I can fall back on the copper when the fiber fails (again), but at some point I might not be given the choice and I need that second line and its specific number.
This is what spurred the initial question: when I'm given no other choice and am forced to give it up, do they add the second line to the current BBU and does that effect battery life. You answered that (yes, and not really), so thanks, and I'll hope I'm not forced into the conversion.
And yet, Hurricane Sandy destroyed the FiOS NID (the various connections inside it for the house are all metal), but the copper kept working. Had phone service working right after Sandy with the copper, but nothing with FiOS for almost four weeks-- Verizon refused to come do the repair until full grid/house power was restored.
FiOS doesn't use a NID, it uses an Optical Network Terminal or ONT. ONTs are active electrical devices. The BBU powers the ONT from mains A/C or the backup battery. They can be mounted inside or outside. Outside units can survive a lot of weather, but Sandy was certainly an exceptional event. An inside unit might have fared better. No ONT can survive flooding (especially salt water) regardless of inside or outside mounting. BBUs and power supplies are always mounted inside.
If your ONT is currently mounted outside, you might want to investigate moving it inside. You might want to consider moving it and the BBU higher to reduce the risk of flood damage. Of course, this all depends on how your home is built.
You're lucky the copper stayed up. As I'm sure you're aware, some areas had the copper ripped out by Sandy's surge and Verizon isn't re-installing it. I doubt that fiber would survive being ripped of the pole any better than copper; but Verizon appears a bit more interested in maintaining fiber over copper.
Anyway, it is a complicated set of issues you're dealing with. At least now you know that if you enable a second line on FiOS it will use your existing ONT and BBU. You also clearly understand your options for backup power.
As this thread is now over two years old, it will be locked in order to keep discussions current. If you have the same or a similar question/issue we invite you to start a new thread on the topic.