Traction elevators are one of the most common types of elevators used in residential and commercial applications. Compared to other types of elevators, traction elevators are more efficient and stable. Before installing a traction elevator, we need to understand its principles first so that the elevator can perform to its maximum performance.

How traction elevators work

Traction elevators use a system of ropes, pulleys, and counterweights to move the elevator car up and down. The system is driven by a motor, which drives the ropes through a pulley (a large pulley) in the machine room. The elevator car is attached to one side of the rope and the counterweight is attached to the other side. This balance allows the system to operate efficiently, and the counterweight offsets the weight of the elevator car, making it easier for the motor to drive the car.

Some traction elevators also have gears between the motor and the pulley (geared elevators), while other traction elevators connect the motor directly to the pulley (gearless elevators).

To ensure safety, the cables/ropes are usually made of multi-strand steel, which means that if one of the steel strands breaks, the cable can still support the elevator car.

Usually, the operating machinery is housed in a separate room called the machine room. When considering a traction lift, it is important to remember that space for a machine room is required (although this is clearly indicated on most drawings). However, there are some “machine room-less” (MRL) traction lifts, such as the GLE RHINO Goods Lift Classic, which has a machine room on top that is only 500mm above the top.

How do traction elevators use energy?

Traction elevators are powered by electricity, with a drive motor that drives the elevator car. The motor uses the electricity to turn the sheave and transfer mechanical force to the ropes that drive the elevator. The energy consumption of a traction elevator depends on a number of factors, including the height at which the elevator needs to travel, the weight of the elevator car, and how often it is used.

One of the most energy-efficient features of traction elevators is the use of counterweights. The counterweights offset some of the load, reducing the energy required to move the elevator car. This means that the motor does not need to bear as much load, saving electricity and reducing overall energy consumption. Traction elevators are particularly suitable for multi-story buildings, where the energy savings are even greater.

Energy consumption of traction elevators

In general, traction elevators are more energy-efficient than other types of elevators, especially compared to hydraulic elevators. Although energy consumption varies depending on building height and usage, traction elevators generally consume less power due to the use of a counterweight system. For example, the average daily power consumption of a traction elevator in a 10-story building is between 3 and 5 kWh, depending on the frequency of operation and load capacity of the elevator. In contrast, hydraulic elevators tend to consume more energy because they rely on hydraulics to drive the car, which requires more energy for each operation.

Safety features of traction elevators

Traction elevators are generally equipped with a number of safety devices to ensure passenger safety. Taking the BDFUJI elevator traction passenger elevator as an example, it is equipped with emergency brakes, overload sensors, safety doors, infrared light curtain systems, communication systems, etc.

Here is a detailed description of these safety features:

• Emergency brake: If the elevator exceeds the normal speed or fails, the emergency brake will be activated to stop the elevator and prevent accidents.
• Overload sensors: These sensors detect if the elevator’s load exceeds its rated load and prevent it from operating in unsafe conditions.
• Safety doors: Traction elevators are equipped with automatic doors that only open when the elevator is properly aligned with the ground, ensuring that passengers do not accidentally step into an open shaft.
• Communication system: In an emergency, passengers can use the communication system to alert building staff or emergency services.

At the same time, in order to ensure our safe use of elevators, we must also perform regular maintenance and safety inspections on traction elevators.

Advantages and disadvantages of traction elevators

Advantages

• Energy saving: Traction elevators are more energy-efficient than hydraulic elevators. The counterweight system of traction elevators helps balance the load of the elevator car, thereby reducing the energy consumption required for operation. This makes traction elevators ideal for multi-story buildings, as the energy saving effect of such buildings is more significant.
• Smooth operation: Traction elevators are known for their smooth and quiet operation. Compared with other types of elevators, such as hydraulic elevators, which may generate more noise and vibration, traction elevators provide a more comfortable riding experience.
• Faster speeds: Traction elevators operate at higher speeds, making them ideal for high-rise buildings. The motor and pulley system provides a more efficient mechanism for lifting the elevator car, which increases the elevator’s operating speed.
• Higher passenger capacity: Traction elevators are able to carry heavier loads than hydraulic elevators. This is particularly useful for commercial buildings that require high passenger capacity.
• Reduced space requirements: Unlike hydraulic elevators, which require large hydraulic pistons and oil tanks, traction elevators use compact motors and counterweight systems, which saves space and allows for more flexible installation.
• Longer service life: Traction elevators typically have a longer service life than hydraulic elevators because their mechanical parts experience less wear and tear. The use of counterweights helps to reduce the strain on the motor.

Disadvantages

• High initial cost: Traction elevators typically have a higher upfront cost than hydraulic elevators. Installing a traction elevator requires a more complex pulley and counterweight system, which increases the owner’s initial investment.
• Requires a machine room: One of the disadvantages of traditional traction elevators is the need for a separate machine room. The machine room houses the motor, pulleys, and other components necessary for the elevator to operate. This requires additional space within the building, which may not always be feasible for certain types of buildings.
• Maintenance costs: Traction elevators, while reliable, require regular maintenance to ensure the system operates smoothly. Ropes, pulleys, and counterweights all need to be checked regularly, and any damage or wear will result in increased maintenance costs over time.
• Suitable only for high-rise buildings: Traction elevators are best suited for mid- to high-rise buildings. For low-rise buildings, other types of elevators, such as hydraulic elevators or machine room-less elevators (MRLs), may be more cost-effective.
• Complex installation: Traction elevators can be more complex and time-consuming to install than other systems. It requires careful planning of the elevator shaft, machine room, and other structural components to accommodate the system.
• Energy consumption when carrying heavy loads: Traction elevators, while energy-efficient, use more energy when carrying heavy loads. The motor must work harder to lift the car, which increases energy consumption during peak hours or when the elevator is overloaded.

Traction elevators are an essential part of modern buildings, providing passengers with smooth, energy-efficient, and safe rides. By understanding how these elevators work, their energy consumption, and their safety features, you can make an informed decision when choosing an elevator system.