Calculate emergency lighting battery runtime and check compliance with the 90-minute AS/NZS 2293.1 requirement.
Enter luminaire wattage and battery specs to calculate runtime.
AS/NZS 2293.1 requires minimum 90 minutes emergency operation at rated illuminance. Verify battery age and temperature derating on site.
AS/NZS 2293.1 requires emergency luminaires to operate for a minimum of 90 minutes after mains power failure. This applies to both escape route and open-area emergency lighting. Central battery systems and self-contained luminaires must both meet this requirement.
NiCd batteries are prone to the "memory effect" if not fully discharged regularly, and they degrade with age and temperature cycling. After 3–5 years, most NiCd batteries deliver significantly less than their rated capacity. Regular full-duration testing per AS/NZS 2293.2 reveals when batteries need replacement.
NiCd (nickel cadmium) has historically dominated due to its wide temperature range and long cycle life. NiMH offers higher capacity in the same size. Li-ion is increasingly used in LED emergency luminaires for its higher energy density and longer service life. Each has different temperature derating requirements.