A surveillance system is only as reliable as its power. The moment the grid drops, cameras, recorders, and switches go dark — and that is often exactly when continuous footage matters most. Sizing a UPS for CCTV is about honest load math and enough battery to cover 24x7 security through real outages.

The Loads to Cover

A typical CCTV setup includes IP or analog cameras, a network video recorder (NVR) or DVR, PoE switches, and sometimes a monitor and networking gear. Cameras individually draw little, but a large multi-camera site plus recorders and PoE switches adds up — and recorders must stay powered to keep writing footage.

Why Pure Sinewave Matters

NVRs, DVRs, and PoE switches use switch-mode power supplies that prefer a clean sine wave. A modified/quasi-sine output can cause recorders to run hot or behave erratically. Paradyne's pure sinewave LI UPS delivers true sinewave output for these loads; for larger or more critical installations, a double-conversion online UPS adds zero transfer time and full isolation. The difference is explained in pure vs modified sinewave.

Sizing for 24x7 Runtime

Surveillance backup is a runtime problem more than a capacity problem — the load is modest but must stay up for hours. Total your camera + NVR + switch watts, then size the battery for your target backup duration using how to calculate UPS battery backup time. Plan realistic autonomy (e.g., enough to outlast typical local outages), and remember the charger must support any larger battery bank you add.

Outdoor and Heat Considerations

Surveillance gear often sits in hot enclosures or remote points. Heat shortens battery life, so plan ventilation and choose a UPS rated for the environment (Paradyne's range operates to 50°C). A wide input window reduces battery cycling on unstable feeders.

What to Specify

• Pure sinewave (LI) for standard sites; online for critical/large installs.

• Battery autonomy sized to your real outage durations.

• Charger rated for the full battery bank.

• Environmental rating and wide input tolerance.

Related: UPS for retail and UPS for telecom sites. Tell us your camera count and runtime target and we will size it.