Battery Capacity Calculator

Calculates theoretical Ah from standby and alarm current, then applies design margin and usable-capacity derating.

Inputs

Standby current Standby duration (hours) Alarm current Alarm duration (minutes) Design / ageing margin (%) Usable battery capacity (%)

Required nominal capacity — Ah

Standby energy—

Alarm energy—

Before derating—

Suggested common size—

Verify standby period, alarm period, battery type, charger capacity and PSU certification against the specific panel manufacturer and current project requirements.