Lupaman
Member
- Location
- Philadelphia, PA
- Occupation
- Fire Protection Engineer
All fire alarm systems require two separate power sources:
Some occupies require the fire alarm system’s primary power connected to an emergency generator (Type 10, Level 1). In these situations, NFPA 72 [2019]10.6.7 Secondary Power Supply permits the secondary battery size may be reduced.
Per NFPA 72 10.6.9 [2019], both the primary and secondary power sources must be monitored for power. Failure must result in a trouble signal in accordance with Section 10.15. All modern UL listed fire alarm panels will provide this feature; the panels self-supervise their primary and backup power sources and will annunciate the condition along with recording the event in the history log. The fire alarm panel will not inherently report generator status unless additional addressable monitoring modules supervise
In a high-rise application an emergency generator status panel and an automatic transfer switch remote annunciator is required in the fire command room, which is provided by the generator company. For all other occupancies, the IBC Section 2702 Emergency and Standby Power Systems does not addressed the issue. Alternately NFPA 101 specifically requires the fire alarm to monitor the emergency generator for operation, fault, and transfer switch position. This supervision is typically accomplished with fire alarm monitoring modules supervising Form C contacts. The codes require surge protection where fire alarm circuits enter or exit buildings (NFPA 72 12.2.4.2 & NEC 760.32).
Emergency generators by NEC definition is termed "Legally Required Standby Systems" These systems must annunciate fault conditions ‘where practicable.’ The NEC does not mandate this annunciation or address the location for these audible and visual signal devices. A dedicated generator status annunciator is one method to satisfy the code. Other supervision methods are by the Fire Alarm, BMS or security system; are all acceptable by NEC. It becomes a specification and AHJ issue.
While supervising a generator may seem like a good practice and may be code-mandated, it is not recommended. Generator testing occurs regardless of your monitoring status. The fire alarm will annunciate the generator’s weekly activity, similar to a weekly fire pump churn test. Someone must acknowledge the event in order to clear it. The weekly testing can then create apathy for responses to status signals. When generator monitoring is incorporated into the fire alarm system, programmed the events as supervisory signals which are non-latching/ self-restoring.
The fire alarm design should specifically include or exclude monitoring of the emergency generator on the contract documents, based on the code and best practices. The fire alarm shop drawings should also clearly indicate if the generator is supervised to ensure compliance with the design engineers intent.
Referenced codes:
NEC Article 701.8 Signals
Audible and visual signal devices shall be provided, where practicable, for the purposes described in 701.6(A), (B), (C), and (D).
NFPA 101 [2021] 9.1.3.2
New generator controllers shall be monitored by the fire alarm system, where provided, or at an attended location, for the following conditions:
• Primary: Usually normal 120VAC building power on a dedicated breaker
• Secondary: Internal storage batteries (two 12-volt batteries in series)
Some occupies require the fire alarm system’s primary power connected to an emergency generator (Type 10, Level 1). In these situations, NFPA 72 [2019]10.6.7 Secondary Power Supply permits the secondary battery size may be reduced.
Per NFPA 72 10.6.9 [2019], both the primary and secondary power sources must be monitored for power. Failure must result in a trouble signal in accordance with Section 10.15. All modern UL listed fire alarm panels will provide this feature; the panels self-supervise their primary and backup power sources and will annunciate the condition along with recording the event in the history log. The fire alarm panel will not inherently report generator status unless additional addressable monitoring modules supervise
In a high-rise application an emergency generator status panel and an automatic transfer switch remote annunciator is required in the fire command room, which is provided by the generator company. For all other occupancies, the IBC Section 2702 Emergency and Standby Power Systems does not addressed the issue. Alternately NFPA 101 specifically requires the fire alarm to monitor the emergency generator for operation, fault, and transfer switch position. This supervision is typically accomplished with fire alarm monitoring modules supervising Form C contacts. The codes require surge protection where fire alarm circuits enter or exit buildings (NFPA 72 12.2.4.2 & NEC 760.32).
Emergency generators by NEC definition is termed "Legally Required Standby Systems" These systems must annunciate fault conditions ‘where practicable.’ The NEC does not mandate this annunciation or address the location for these audible and visual signal devices. A dedicated generator status annunciator is one method to satisfy the code. Other supervision methods are by the Fire Alarm, BMS or security system; are all acceptable by NEC. It becomes a specification and AHJ issue.
While supervising a generator may seem like a good practice and may be code-mandated, it is not recommended. Generator testing occurs regardless of your monitoring status. The fire alarm will annunciate the generator’s weekly activity, similar to a weekly fire pump churn test. Someone must acknowledge the event in order to clear it. The weekly testing can then create apathy for responses to status signals. When generator monitoring is incorporated into the fire alarm system, programmed the events as supervisory signals which are non-latching/ self-restoring.
The fire alarm design should specifically include or exclude monitoring of the emergency generator on the contract documents, based on the code and best practices. The fire alarm shop drawings should also clearly indicate if the generator is supervised to ensure compliance with the design engineers intent.
Referenced codes:
NEC Article 701.8 Signals
Audible and visual signal devices shall be provided, where practicable, for the purposes described in 701.6(A), (B), (C), and (D).
(A) Malfunction.
Malfunction signals indicate a malfunction of the standby source.
(B) Carrying Load.
Load carrying signals indicate that the standby source is carrying load.
(C) Battery Charging Malfunction.
Battery charging malfunction signals indicate charging malfunction on a battery required for source readiness, including the prime mover starting battery.
Informational Note: See NFPA 110-2019, Standard for Emergency and Standby Power Systems, for signals for generator sets.
(D) Ground Fault.
Ground-fault signals indicate a ground fault in solidly grounded wye, legally required standby systems of more than 150 volts to ground and circuit-protective devices rated 1000 amperes or more. The sensor for the ground-fault signal devices shall be located at, or ahead of, the main system disconnecting means for the legally required standby source, and the maximum setting of the signal devices shall be for a ground-fault current of 1200 amperes. Instructions on the course of action to be taken in the event of an indicated ground fault shall be located at or near the sensor location.
For systems with multiple emergency sources connected to a paralleling bus, the ground-fault sensor shall be permitted at an alternate location.
NFPA 101 [2021] 9.1.3.2
New generator controllers shall be monitored by the fire alarm system, where provided, or at an attended location, for the following conditions:
1) Generator running
2) Generator fault
3) Generator switch in nonautomatic position
