Battery Backup

Backup Power for Home Phone Services during Power Outages

For many years, your home phone would allow you to stay connected to emergency voice services during a power outage. However, many of today’s advanced home phone services require backup battery power to continue functioning during an outage.  To avoid a disruption of home voice service during an outage –and to maintain the ability to connect to 911 emergency services — we at Rainbow offer you the option of purchasing backup power for your home phone.

What Your Battery Can – and Cannot – Do for You

Rainbow backup batteries for telephone modems and optical network terminals (ONTs) allow you to continue to use your home voice services during a power outage. Without a backup battery or alternate backup source such as a generator, customers will not be able to make any calls, including emergency calls to 911. The only way to maintain the ability to use your phone is by using some form of backup power.

Our backup battery does not provide power to any services other than voice.

Inability to use Cordless Phones and Other Devices During a Power Outage

If you have a cordless phone, it will not work during a power outage as your cordless phone requires power from an external power source like an electric outlet in your home. To use your cordless phone, you would need to power the cordless phone with a backup generator or UPS (Uninterruptible Power Supply). To use Rainbow’s voice service during power outages, we suggest that you keep a corded phone on hand. Corded phones, unlike cordless phones, do not need a separate power source to operate.

Rainbow’s backup battery only provides backup power to Rainbow voice service. Devices that rely on voice service, such as home security systems, medical monitoring devices, TTY devices, and other equipment may be disrupted if there is an electrical power outage unless those devices are powered by an alternate power source such as a generator or UPS (Uninterruptible Power Supply). These type of alternate power sources are available from third party retail vendors.

Battery-Backup Purchase and Replacement Options

If you are concerned about being able to contact 911 emergency services during a power outage, a backup battery may be a good option for you.

You can purchase a backup battery directly through Rainbow. If you have any questions or simply want to purchase a backup battery through us, please call 1-800-892-0163. Our 8-hour backup batteries cost approximately $65. If you do not feel comfortable installing your own battery, please call us to make an appointment and we would be happy to assist you.  However, please note that there may be a charge for this service.

Expected Backup Power Duration

Backup batteries are expected to last at least 8 hours on standby power. The backup battery should give you approximately 6 hours of talk time. If you feel that is not enough time, you may extend your standby power by purchasing a 24-hour battery or additional 8-hour batteries.

Battery Use

Environmental factors such as temperature can shorten your battery’s useful life. We recommend that you store your battery above 32°F and below 122°F.  The battery should last 3 to 5 years under normal operating conditions.


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