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Fire Alarm Battery Sizer

Standby plus alarm capacity per NFPA 72 with 20% margin. 4 inputs, 2 outputs.

Inputs

Load

Quiescent panel current.

NFPA 72 default is 24 h.

Full alarm load.

NFPA 72 default is 5 min.

Result

Required capacity
Waiting for calculation.
Standard battery
Waiting for calculation.
Screening calculation only. Verify against NEC articles cited on the page and the equipment nameplate; the authority having jurisdiction governs.

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Workspace

Keep the assumptions with the result.

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