Backup Power Requirements for Elevators

Electrical power is crucial for sustaining operations. They serve industries like health care, hospitality, food service, and manufacturing. Many establishments require a backup generator to keep things moving even when the power goes out. Buildings with elevators have even more stringent regulations protecting the occupants’ health and safety in case of power failures.

Do Elevators Have Backup Power?

The International Building Code (IBC), in use across the U.S., states that elevators are required to be on a building’s emergency power. The IBC outlines the following elevator emergency power requirements:

  • Fire access elevators: According to Section 3007.8, all fire service access elevators must connect to both standard power and the building’s standby power supply. This requirement includes all associated electrical equipment and hoistway lighting.
  • Passenger elevators: Like Section 3007.8, Section 3008.8 requires the features of an occupant elevator to receive power from the normal and standby power supplies. This section also adds emergency lighting to the list of elevator backup power requirements.
  • Egress illumination: The IBC defines a means of egress as a continuous, unobstructed path from any occupied space to an outdoor public space. Egress illumination includes any lighting posted between elevators and a direct exit. All egress illumination must connect to an elevator’s emergency lighting power supply in case of emergencies.
  • Machine room ventilation: Machine room air conditioning and ventilation systems must connect to the standby power source. Before finalizing, an electrical engineer must ensure that this extra load is within the generator’s power capacity.

Typical Elevator Specifications

An elevator’s weight and capacity vary depending on its application. Passenger elevators are typically smaller and lighter than freight or automobile elevators. As a result, the power requirements for each different elevator type also vary. Heavier applications usually need more power than passenger elevators in homes and businesses.

Most commercial buildings currently use two main types of elevators:

  • Hydraulic: The main advantage of hydraulic elevators is that they work well in simple building structures. These elevators work using a piston system. Pumping hydraulic oil into the cylinder makes the piston move, lifting the cab. Then a system of electrical valves slowly releases the oil to enable a smooth, controlled descent.
  • Traction: Geared and gearless traction elevators operate in similar ways. Above the elevator shaft, the cables pass over a wheel called the sheave. An electric motor attaches directly to the sheave in gearless elevators or through a gearbox in geared ones. A counterweight balances the weight of both the cab and its riders to let the cab ascend and descend. Since the counterweight system powers most of the lifting, the motor only kicks in when friction interferes with the operation.

Types of Standby Power Supplies

When you’re determining the right standby power supply for your building, you have two options:

  1. Uninterrupted power supply (UPS): A UPS is a battery-powered backup power system. The UPS kicks in almost instantaneously during a power failure to ensure a continuous power supply. While elevator battery backup costs are generally lower upfront, a UPS may not provide enough power to sustain operations for long periods.
  2. Backup generator: A generator works by converting mechanical energy into electrical power. While the source of that mechanical energy can vary, the most common sources are gasoline and diesel. Additionally, while generators take a few seconds longer to start up than UPS, they can sustain your operations for much longer.

A generator is usually the best option for buildings that require lots of power because it will keep the power on for longer. The two most common sources of mechanical energy for generators include:

  • Gasoline: Gas-powered generators are generally easy to operate and cost less upfront than diesel generators. They’re also quieter than diesel generators, making them suitable for residential or school buildings where silence is necessary.
  • Diesel: Because diesel is an energy-dense fuel, diesel-powered generators are more efficient and cost-effective. Diesel is also less flammable than other fuel sources, making it a safe choice for large establishments.

Your generator will likely power more than just one elevator when the power goes out, so choose a fuel source that makes the most sense for your building and application. Consulting with a sales representative can help you find the best generator model for your establishment.


What Happens to an Elevator When the Power Goes Out?

Understanding elevator operation during power failures can help inform evacuation procedures. Some elevators have a battery lowering system — also known as an automatic rescue device — that activates once normal power disconnects. This feature safely lowers the elevator to a nearby level and opens the doors to allow passengers to exit. However, the elevator needs more power to begin running again.

When you have a backup generator, you’ll have a limited power supply in your elevators. Although regulations on power breakdown vary depending on location, the generator should activate within 60 seconds to provide power to at least one of the elevators in the building. The number of operable elevators will depend on the type of elevator and your generator’s capacity.

When power resumes, the elevator should return to operating as usual. However, power surges can sometimes damage an elevator. Always inspect elevators after a power failure to ensure they are safe before resuming operation.

The Importance of Backup Generators

A backup generator is crucial for keeping critical systems functioning in any building. For example, a power outage in a hospital could result in disastrous consequences when life-saving machines lose power. In a high-rise apartment building, losing power could trap residents on the top floors during natural disasters like tornadoes or earthquakes when it’s essential to be at or below ground level.

Installing a backup generator can prevent emergencies from turning into catastrophes. From supplying elevators with enough power to get people out of the building to keeping food fresh in a restaurant, a standby generator can save money, resources, and lives.

Choose Standby Generators From Caterpillar

When you need power, you can rely on Caterpillar to equip your building with a sturdy, reliable elevator generator that’s built to last. Cat® standby generators come in a range of sizes and configurations. Whether you need an industrial diesel generator to power several elevators at once or a small, portable generator to power a home elevator system, you’ll be able to find one that fits your application.

Cat generator systems are known for their quick response times and dependable operations. Read some of our testimonials to see why Cat is the best choice for standby power supplies.

Trust Thompson Power Systems for Cat® Standby Generators

At Thompson Power Systems, we understand the importance of uninterrupted power. If you’ve got questions about the best elevator generator for your situation, we’ve got answers. Contact us online to set up a consultation on the exact generator you need for your specific applications and power requirements or click here to find your nearest location. We’re here to help you.

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