What are the security measures in passenger lifts?

Passenger lifts are an integral part of modern buildings, providing convenient vertical transportation for people. As a passenger lift supplier, ensuring the safety of passengers is our top priority. In this blog, we will explore the various security measures implemented in passenger lifts to safeguard the well - being of users.

1. Mechanical Safety Devices

1.1 Over - speed Governor and Safety Gear

The over - speed governor is a crucial mechanical device in a passenger lift. It continuously monitors the speed of the lift car. If the lift car exceeds a pre - determined safe speed, the over - speed governor will trigger the safety gear. The safety gear is designed to grip the guide rails firmly, bringing the lift car to a safe stop. This mechanism is essential in preventing high - speed falls and protecting passengers from potential harm. For example, in case of a sudden cable break or a malfunction in the drive system, the over - speed governor and safety gear work in tandem to halt the lift car and avoid a catastrophic accident.

1.2 Buffer

Buffers are installed at the bottom of the lift shaft. There are two main types: hydraulic buffers and spring buffers. When the lift car descends at a high speed and reaches the bottom of the shaft, the buffer absorbs the impact energy. Hydraulic buffers are more commonly used in high - speed lifts as they can provide a smoother and more controlled stopping force. The buffer acts as a last - line of defense, reducing the impact on the passengers inside the lift car in case of an emergency descent.

1.3 Counterweight and Rope Safety

The counterweight in a passenger lift helps balance the weight of the lift car and its passengers. It reduces the amount of energy required to operate the lift. However, the ropes that connect the lift car and the counterweight are under constant stress. Regular inspections of the ropes are necessary to check for signs of wear, corrosion, or fraying. If any issues are detected, the ropes should be replaced immediately to prevent a potential failure that could lead to an accident.

2. Electrical Safety Features

2.1 Emergency Power Supply

An emergency power supply is a vital electrical safety feature in passenger lifts. In the event of a power outage, the emergency power supply can provide enough electricity to move the lift car to the nearest floor and open the doors. This allows passengers to exit the lift safely. The emergency power supply is usually in the form of a battery or a generator. It is regularly tested to ensure its reliability.

2.2 Electrical Protection Devices

Passenger lifts are equipped with various electrical protection devices such as circuit breakers and fuses. These devices protect the lift's electrical system from short - circuits, overloads, and other electrical faults. Circuit breakers automatically cut off the electrical supply when an abnormal current is detected, preventing damage to the electrical components and reducing the risk of fire. Fuses, on the other hand, are sacrificial devices that melt when the current exceeds a certain limit, also interrupting the electrical circuit.

2.3 Control System Safety

The lift's control system is the brain of the operation. It manages the movement of the lift car, the opening and closing of the doors, and the communication between different components. To ensure its safety, the control system is designed with redundant circuits and fail - safe mechanisms. For example, multiple sensors are used to detect the position of the lift car and the status of the doors. If one sensor fails, the others can still provide accurate information, preventing the lift from operating in an unsafe condition.

3. Door Safety Mechanisms

3.1 Door Sensors

Door sensors are installed on the edges of the lift doors. These sensors can detect any obstruction when the doors are closing. If an object or a person is detected, the doors will immediately reverse their movement and open again. This prevents passengers from being trapped or injured by the closing doors. There are different types of door sensors, including infrared sensors and mechanical sensors. Infrared sensors use light beams to detect obstacles, while mechanical sensors rely on physical contact.

3.2 Door Interlocks

Door interlocks are safety devices that ensure the lift car cannot move unless the doors are properly closed and locked. They are designed to prevent the lift from operating when the doors are open, which could lead to passengers falling out of the lift car. The door interlocks are mechanically and electrically connected to the lift's control system. If the interlocks detect that the doors are not properly secured, the lift will not move.

4. Communication and Monitoring Systems

4.1 Emergency Communication

Passenger lifts are required to have an emergency communication system. This system allows passengers to contact the building management or a monitoring center in case of an emergency. The emergency communication device is usually a two - way intercom located inside the lift car. It provides a direct line of communication for passengers to report problems, such as being trapped in the lift or a medical emergency.

4.2 Monitoring and Diagnostic Systems

Modern passenger lifts are often equipped with monitoring and diagnostic systems. These systems continuously collect data on the lift's performance, including speed, acceleration, and door operation. The data is transmitted to a central monitoring station, where technicians can analyze it in real - time. If any abnormal behavior is detected, the technicians can take proactive measures to prevent potential problems. For example, if the system detects a gradual increase in the lift's stopping time, it could indicate a problem with the brakes, and maintenance can be scheduled before a major failure occurs.

5. Fire and Smoke Safety

5.1 Fire - rated Construction

Lift shafts and lift cars are often constructed with fire - rated materials. These materials can withstand high temperatures for a certain period, preventing the spread of fire and smoke through the lift shaft. Fire - rated doors are also installed at the entrance of the lift car and at each floor level. These doors can close automatically in case of a fire, isolating the lift car from the fire - affected areas.

5.2 Smoke Detectors

Smoke detectors are installed inside the lift car and in the lift shaft. When smoke is detected, the lift's control system will automatically send the lift car to a pre - determined safe floor, usually the ground floor or a designated refuge floor. The doors will then open, allowing passengers to evacuate safely.

As a passenger lift supplier, we offer a wide range of passenger lifts to meet different needs. Our Electric Passenger Lift is known for its energy - efficiency and smooth operation. For smaller spaces, our Small Passenger Lift provides a compact and practical solution. And if you only need to transport a small number of people, our 2 Passenger Lift is a great choice.

We understand the importance of safety in passenger lifts, and all our products are designed and manufactured in strict accordance with international safety standards. If you are interested in purchasing passenger lifts for your building, we invite you to contact us for a detailed consultation. Our professional team will be happy to assist you in finding the most suitable lift solution for your needs.

References

• International Organization for Standardization (ISO). ISO 4190 - 1:2017, Lifts (elevators) – Installation and equipment of lifts – Part 1: Passenger lifts and goods passenger lifts.
• American Society of Mechanical Engineers (ASME). ASME A17 - 1/CSA B44 Safety Code for Elevators and Escalators.
• European Committee for Standardization (CEN). EN 81 - 20:2014+A1:2018, Safety rules for the construction and installation of lifts – Part 20: Passenger and goods passenger lifts.