Keep the Doors On During a Blackout: Power & Battery Basics

Quick intro: The best systems fail gracefully. Here’s a quick blueprint.

Plan the load

• Add up the amp draw of locks + readers + controller (at the actual voltage).

• Choose a supervised power supply sized at 125–150% of normal load.

• Decide your standby time goal (common targets: 4–8 hours).

Battery sizing (rule of thumb)

• Required Ah ≈ (Total amps × hours of standby). Example: 2.0A load × 4h ≈ 8Ah battery.

• Use proper 12V or 24V to match the supply. Parallel packs for longer runtime; don’t mix old/new batteries.

Good habits

• Quarterly check: battery test, fuse/LEDs, and event log review.

• Label supplies with install date and next test date.