Regulatory framework
Fire alarm system power supply is governed by SP 5.13130, SP 6.13130, and IEC 60364. Fire alarm loads belong to Category I (critical) reliability.
Reliability category
Category I requires two independent power sources with ATS. Main supply + battery backup. Transfer time — max 3 seconds.
Cable lines
Fire alarm cables must be fire-resistant (FR) and flame-retardant. Marking: FRLS, FRHF. Routing in separate conduits. 180-minute survivability (E180) for evacuation routes.
Battery sizing
Battery capacity: C = (Istandby × 24 + Ialarm × 3) × 1.25. Where Istandby — standby current, Ialarm — alarm current (all sounders active), 24 and 3 — hours per standard.
Frequently asked questions
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