Why a public-address voice-alarm (PAVA) system draws almost nothing in supervision but demands a high, speech-shaped current the moment a building must be evacuated, and what EN 54-16 and EN 54-4 require of its NiMH backup.
Paper C assembles the life-safety evidence for a fire-panel battery: EN 54-2 and EN 54-4 type tests, EN 54-13 compatibility, BS 5839 and UL 864/NFPA 72 context, IEC 61951-2, IEC 62133-1 and UN 38.3.
Paper B turns the EN 54-4 duty into a sizing method: the quiescent-plus-alarm energy budget formalised by BS 5839-1 Annex E, a chemistry scorecard, 24 V pack architecture, supervision thresholds and the float-charger design.
A fire panel must supervise its loops for a day on battery, then drive every sounder and beacon in full alarm. Paper A dissects that duty under EN 54-2 and EN 54-4 and maps it onto NiMH.
Paper C assembles the evidence for a small-UPS or instrument backup battery: IEC 62040-1 safety and 62040-3 performance classification, 62040-5 DC UPS, ride-through and recharge verification, IEC 61951-2, IEC 62133-1 and UN 38.3.
Paper B converts the ride-through duty into a sizing method: load and bridge-time energy budget, a chemistry scorecard against supercapacitors, VFD/VI/VFI and DC-UPS architecture, high-rate cell choice and the charger design for repeated outages.
A small UPS or instrument backup exists to bridge a mains disturbance for seconds to minutes. Paper A dissects that ride-through duty and the VFD, VI and VFI topologies defined by IEC 62040-3, mapping them to NiMH.
Paper C assembles the certification evidence for lift emergency batteries: EN 81-20 and EN 81-28 functionality tests, the one-hour standby and talk verification, five-party coverage, IEC 61951-2, IEC 62133-1 and UN 38.3.
