The use of generators as a backup power source during power outages is well-known, but many people often confuse the terms “emergency generator” and “standby generator.” While both types of generators operate on fuel to produce electricity, they serve different purposes and are classified differently. Understanding these differences can help you choose the right option for your facility. Generators are typically paired with UPS systems, which provide temporary power during the critical seconds or minutes needed for a generator to start up.

Applications Requiring Emergency Generators (Level 1)

The choice between emergency and standby power is usually guided by fire safety or building codes, with specific requirements varying based on factors like occupancy type, facility use, and critical functions. The National Fire Protection Association (NFPA) specifies generator types in its NFPA 110 code. A Level 1 emergency power system, or emergency generator, is required for operations essential for life safety. Conversely, a Level 2 system, also known as a legally required standby generator, is used where system failure is less critical to human life and safety.

Emergency power generators are designed to automatically kick in during an outage to power critical systems. These generators start up in about 10 seconds, much faster than the one minute needed by standby generators. They are powered by fuel sources like diesel, propane, or natural gas, which can be stored onsite or delivered as needed. Emergency generators operate independently with their own conduits and panels, ensuring a consistent electricity supply when needed most.

Emergency generators are typically installed in places requiring artificial illumination for safe exiting and panic control in high-occupancy buildings such as hotels, theaters, sports arenas, healthcare facilities, and similar institutions. Common uses include illuminating exit signs, powering fire pumps where secondary power is needed, ensuring fire detection and alarm systems remain operational, providing elevator lighting, and maintaining emergency voice/alarm communication systems. In hospitals, NFPA 110 requires emergency generators to support vital medical equipment such as respirators. Radio systems for firehouses, police stations, and 911 operators also rely on emergency generators to ensure emergency services can respond in any situation.

Applications for Legally Required Standby Generators (Level 2)

While emergency power systems are critical to life safety, standby systems are considered less essential. There are two types of standby generators: legally required and optional. Legally required standby power systems are not critical to life, but their absence could hinder firefighting operations or rescue efforts. As such, they are specified by NFPA codes just like emergency generators.

Standby generators are less expensive than emergency systems and slower to respond to power losses. Legally required standby systems have 60 seconds to automatically transfer the load, compared to 10 seconds for emergency systems. Additionally, it is permissible for the wiring of a legally required standby system to share raceways, cables, boxes, and cabinets with general wiring. Like emergency systems, standby generators are powered by diesel, propane, or natural gas.

Legally required standby power systems are typically installed to serve loads such as heating and refrigeration systems, communication systems, ventilation and smoke removal systems, sewage disposal, and lighting systems. They may also support some medical devices and industrial processes that could create hazards if the power fails. While some uses sound similar to those of emergency systems, they are not the same. Standby systems may support lighting, but not the essential lighting needed for safe evacuation.

Applications for Optional Standby Generators

Optional generators provide backup power where human life doesn’t depend on the system's performance and have no code requirements. These generators are used as a discretionary measure and have no minimum time requirement for transferring the load.

Many organizations, such as financial services, data centers, and Internet/hosting companies, invest in sophisticated standby backup power systems to avoid any disruption to their critical operations. These systems range from basic to elaborate and often rely on an automatic transfer switch capable of supporting the full load or include a load management system.

Maintain Your Generator with Dingbo Power

Routine maintenance is crucial for ensuring your generator performs properly when needed. Dingbo Power, an emergency and standby generator manufacturer, understands the importance of reliable backup equipment. We provide a 3-year warranty for all our products, ensuring you receive comprehensive after-sales support. With a 24/7 dispatch facility for mission-critical power services, all our services comply with NFPA 110 code requirements for generator services and testing. No matter the type or brand of generator you have, Dingbo Power is ready to handle all your service needs.