Best UPS Battery Backup for an NVR

Why is not the VA rating on the box the number I need?

Volt-amps and watts are different measurements, and consumer UPS units typically have a power factor somewhere around 0.6 to 0.7, meaning the real usable watt rating is roughly 60 to 70 percent of the VA number printed on the front of the box. A 650VA unit rated at 390W and a 425VA unit rated at 255W both work out to almost exactly that ratio, which is why the watt figure, when a manufacturer publishes it, is the one to plan a real system around.

Runtime itself works out to usable battery watt-hours multiplied by the inverter's efficiency, divided by your actual load in watts. Add up the running wattage of your recorder, PoE switch and router, then use the UPS runtime calculator with your UPS's watt-hour capacity to get a real estimate rather than the rough one printed on the box.

Beginner pick: a recorder and router only

The APC BE425M is the smallest unit here and is rated for 255W, published directly alongside its 425VA rating. That covers a recorder and a router through a brief outage, but it is not enough headroom to also carry a fully loaded PoE switch, so size up if your NVR and cameras share a switch on the same circuit.

Intermediate pick: a recorder plus a loaded PoE switch

The APC BE650G1 carries a published 390W rating, enough to run a recorder and a moderately loaded PoE switch and router together through the short outages that make up the large majority of power interruptions, which is also when a camera system is most likely to actually be needed.

Expert pick: a full sixteen channel system

The CyberPower CP1500PFCLCD is rated at 1500VA and 1000W with true sine wave output, which is the waveform the switching power supplies inside a recorder and a PoE switch are actually designed for, rather than the stepped approximation cheaper UPS units produce. It is the unit sized for a full sixteen channel system running a recorder, a loaded switch and networking gear together.

What if I just want a straightforward small system?

The APC BE600M1 does not publish a separate watt rating, but APC states 23 minutes of runtime at a 100W load directly in its own specifications, which is a real, quotable figure rather than an estimate. The CyberPower EC850LCD, at 850VA, adds a display that reports your actual load in watts in real time, turning a runtime estimate into a measurement you can read off the front panel.

How we chose these UPS units

We did not run these units on a bench to failure to measure their real-world runtime. The VA and watt figures above are taken directly from each manufacturer's published specification sheet and product listing, cross-checked for internal consistency between the VA rating, the watt rating and the stated power factor, not from a runtime test we performed ourselves.