Fire alarm panels and elevator phones used to ride on copper POTS lines that carried their own power. As carriers retire copper, those life-safety lines now depend on cellular routers and ATAs powered from the building — and when the building loses power, they go silent unless they have dedicated battery backup.

What codes expect from POTS replacement installs

Life-safety communication paths are expected to stay up during an outage, typically with backup power measured in hours, not minutes. In a copper install the phone company provided that power; in a POTS replacement install, the battery backup at the router is your responsibility. Sizing it correctly is the difference between a compliant install and a dead elevator phone during a blackout.

How much backup runtime do you get?

A typical POTS replacement stack — cellular router plus ATA, around 7W — runs about 8 hours on a 64Wh battery. Divide watt-hours by your load and multiply by about 0.9 to estimate your own runtime, or use our runtime calculator.

Why installers choose a DC mini UPS

The Zeatech ZP-64Wh powers the router and ATA directly at 9V/12V/24V DC or PoE with no wasteful AC conversion, uses LiFePO4 chemistry rated for 2,000+ cycles in unattended closets and risers, signals AC power loss through its DO1 output so your router can alert the NOC the moment building power fails, and supports remote power-cycling by digital I/O or RS232 — no truck roll to reboot a hung router.

Read more about POTS replacement backup power, or see the ZP-64Wh →