Battery Sizing
Sum standby and alarm loads, choose 2022 or pre-2022 correction factor, apply temperature derate, and check 48-hour recharge current.
NAC Voltage Drop
Enter devices in physical order with segment length, AWG, alarm current, and Class B or Class A return-leg modeling.
AHJ Worksheet
Export a PDF worksheet and CSV load schedule with the inputs, math lines, checklist, signature line, and estimate disclaimer.
Built For Field Techs
- Works fully offline. No account, no backend, no analytics, no ads.
- Large steppers and tabular numbers for one-handed use.
- Shows PASS and FAIL at the hero output and per NAC node.
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Safety Scope
FireBatt 72 provides estimates only. It is not a stamped engineering document and is not a substitute for a licensed professional, the engineer of record, device listings, or the authority having jurisdiction.