Phone Modem Battery Backup FAQs

What is the purpose of the telephone modem back-up battery?

Your RCN telephone service is provided via the telephone modem we have installed at your location. This device needs electrical power to provide service. In the event of a power outage, your phone service, including access to 911, will not work, unless you have a working back-up battery installed in your modem.

How can I obtain a telephone modem back-up battery?

Currently, RCN will provide an internal 8-HOUR back-up battery for RCN-supplied telephone modems at no charge, upon request from the customer [and will replace the 8-HOUR back-up battery without charge, upon request, as needed]. Batteries may be obtained at the time your telephone modem is installed or by calling 800.746.4726. This policy may be subject to change at a future date, in which case you will be notified.

How long will the battery power my phone service?

RCN-supplied batteries are rated to provide between 8 and up to 24 hours of standby time when new. Active use of the telephone line during an outage will reduce the amount of standby time provided by the battery. Standby time may also be reduced in cold temperature conditions and as the battery ages.

Will the presence of a working battery ensure I will have phone service?

In the case of a complete power loss, network outage, broadband Internet outages or congestion, disconnection of service, or other conditions beyond the reasonable control of RCN, you may be unable to access 911 or your access to 911 may be delayed or impaired.

If you utilize cordless phones in your home, RCN advises you to keep a corded (landline) phone on hand. Corded phones, unlike cordless phones, don't need a separate power source to operate and can function with a battery backup in your RCN Voice modem during a power outage.

Will the internal battery back up my internet service?

If service is also being used with RCN’s High-Speed Internet ("HSI") service, continued use of the HSI service during a power outage will decrease the battery backup life. Customers who wish to have back up power for both for their internet service and/or extended backup time for their telephone service may purchase from a third-party retailer, at their own cost, an external UPS (Uninterruptable Power Supply). These systems are commonly available through electronics and office supply retailers, whose websites provide additional information on capacity and prices.

How do I verify the status of my battery?

There is an indicator light on the front of your telephone modem

• A solid light indicates the battery is in good condition and fully charged.
• A blinking light indicated your battery is charging. If the light continues to blink after 8 hours, your battery may be weak and may need to be replaced.
• If the battery light is out on the modem device, your battery may be missing, depleted, or not correctly installed.
• If an external battery/UPS is in use, please refer to the manual for that device.

911 Service & Back-up Battery Power