Battery backup

Digital phone service will not work in the event of a power outage unless you have a battery back-up. Quantum Fiber offers a battery backup unit (BBU) for digital voice services.

Electrical power is required for non-line-powered voice services (including Connected Voice) to work. If there is a power outage, digital service will not process calls, including those to Emergency 911.

With active batteries, a BBU will provide temporary backup power during an outage, allowing basic voice services to keep functioning, including the ability to dial 911. Please note that in the event of an outage that impacts the service network as well, the BBU may not guarantee functionality.


You can purchase your battery backup unit from Quantum Fiber or from another supplier.

Important information about battery backups

You are responsible for obtaining, monitoring, replacing and properly disposing of all batteries for the BBU. We recommend you check the BBU at least twice a year to be sure it's operating and ready to use in case of a power outage.


In case of a power outage, the BBU should last at least 24 hours in standby mode. While under BBU power, you may not be able to access the internet. Other services, such as security alarms, may not work.

Important: Failure to maintain your BBU may result in loss of voice service during a power outage, including no access to Emergency 911 and other services.

If you purchased the BBU from Quantum Fiber, our warranty covers the replacement of the battery if it stops working within the first year.


Shop for a battery backup:


Customers with a SmartNID (C5500XK or C6500XK)

Customers with a modem (C4000XG, C3510XZ, or other)


Warranty information and technical assistance are available from Precision Power Solutions
Phone: 615-436-0080