Fire Alarm Backup Systems
NFPA 72 demands 24 hours of standby plus 5 minutes of full alarm — 15 minutes for voice evac. Internal panel batteries cap at 55Ah. Our UL 1481 backup powers the entire fire alarm panel with zero transfer time. 500W to 15kW, supervised charging, Form-C trouble relays.
Responds within 2 business hours
Standby
24hr + 5min alarm
Standard
NFPA 72 §10.6.7.2
Transfer
Zero (online)
Certifications
UL 1481 · NFPA 72
Overview
Back up the entire panel, not just the NAC circuits
NAC power extenders only add notification circuit capacity. Online Power's Fire Alarm Backup provides AC power to the FACP itself, backing up every function: addressable loops, signaling line circuits, NAC outputs, communications, and supervisory circuits. One UPS. Complete protection.
Zero transfer means zero panel reset
Standard battery switchover can cause a momentary power interruption that resets the fire alarm control panel, losing alarm history, zone status, and potentially triggering false trouble signals to the monitoring station. True online double conversion eliminates this risk entirely.
VRLA batteries with 10-year design life
Panel-internal batteries typically last 3-5 years and require semi-annual testing under NFPA 72 §14.4. Online Power's premium VRLA batteries deliver 10-year expected life with 250+ discharge cycles. The integrated supervised charger meets NFPA 72's 48-hour full-recharge requirement per §10.6.10.3.2 and monitors for low voltage, charger failure, and ground faults.
What your spec sheet won't tell you
NFPA 72 §10.6.7.2 requires a 20% safety margin in all battery calculations. The formula is: Battery Capacity (Ah) = [(Standby Current × 24h) + (Alarm Current × 0.0833h)] × 1.20. Most specifiers run this math against panel-internal batteries and find they are undersized on day one. The bigger trap: NFPA 72 §10.6.10.3.2 requires batteries to recharge fully within 48 hours after complete discharge. Many fire alarm panels have chargers sized for their maximum internal battery, not for an oversized external battery bank. An external UPS with its own properly sized charger solves both problems. Also note: effective January 2024 under NFPA 72 2022 edition, all rechargeable batteries used as secondary fire alarm power must be listed per UL 1989 or UL 2054.
Custom Alarm Mode Options
Every building has different fire alarm loads, panel configurations, and code requirements. Online Power engineers each Fire Alarm Backup system to your exact specification. Tell us your panel make and model, your NAC circuit load in amps, your standby current draw, and your jurisdiction and we will size the system, calculate the battery capacity with the NFPA 72 required 20% safety margin, and provide a complete submittal package.
Extended Runtime
Standard NFPA 72 requires 24 hours standby plus 5 minutes alarm. Online Power configures extended runtime batteries for jurisdictions requiring 60 hours, 72 hours, or beyond standard minimums. Ideal for remote facilities, critical government buildings, and projects with stringent AHJ requirements.
Voice Evacuation Systems
Buildings with voice evacuation require 15 minutes of full alarm runtime instead of the standard 5 minutes per NFPA 72. Online Power sizes battery capacity to meet the higher drain of amplifiers, speakers, and mass notification equipment across large floor plates and campus environments.
High Rise and Campus Systems
Large buildings with multiple fire alarm control panels and remote power supplies require coordinated backup across the entire system. Online Power designs multi-unit configurations that maintain NFPA 72 compliance for each panel independently while providing centralized monitoring through a single GMS interface.
Generator Coordination
For buildings with standby generators, Online Power configures the Fire Alarm Backup to bridge the gap between utility failure and generator transfer with zero interruption, then seamlessly hand off to generator power for extended outages without panel reset or false alarm signals.
Codes & Standards
UL 1481
Power Supplies for Fire Alarm Systems
NFPA 72 §10.6.7.2
Standby and Alarm Runtime
NFPA 72 §10.6.10.3.2
48-Hour Recharge Requirement
NEC Article 760
Fire Alarm Systems
NEC Article 700
Emergency Systems
UL 864
Fire Alarm Control Units
Where It Gets Specified
Fire Alarm Panel Compatibility
Compatible with all major fire alarm control panels including Notifier, Simplex, Edwards, and Honeywell. Contact our engineering team for panel compatibility verification.
Key Features
Documents & Downloads
"Online Power is highly responsive with helpful solutions and a range of products for our projects which is why we continue to specify their products."
Sothol Roeung
Electrical Engineer, S Y Lee and Associates
Common Questions