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On Elevator Monitoring in Intelligent Buildings Author: Hu Gang 1 The current relationship between elevator monitoring and low-voltage systems in intelligent buildings in China. Elevators, which have a history of over a hundred years, are well-known important building equipment. In today’s era, with the increasing number of high-rise buildings and the improvement in architectural design standards, people’s expectations regarding elevators are also rising. Today, the requirements extend beyond simply having elevators that are fast and comfortable to ride, sturdy in construction, and well-designed in terms of aesthetics; there is an increasing demand for elevators that are safe, reliable, and multifunctional. As a result, elevators are evolving toward more intelligent control systems. In some of the world’s advanced modern smart buildings, elevators are considered to be important devices under control within the building’s automatic control system. Advanced low-voltage monitoring techniques are used to ensure comprehensive management of the elevators’ operating conditions, maintenance, and safety measures. On this topic, the author previously introduced in the second issue of the 1996 magazine \"China Elevator\" the experience of Singapore’s Housing & Development Board in successfully using computer networking to implement comprehensive management of elevator clusters. In our country, elevators equipped with advanced control technologies have become increasingly common in recent years. In particular, various high-end elevators are used in many newly built smart buildings, which makes it possible to integrate elevator monitoring with low-voltage control in an organic manner. However, due to traditional management concepts and the relative independence of the systems operated by elevator manufacturers and low-voltage equipment suppliers, progress in the technical and application integration between elevator monitoring and low-voltage control in China has been slow. In most high-rise buildings, elevator monitoring is provided by the elevator supplier as a closed system; an elevator monitoring panel supplied by the supplier is installed in the building’s security center, which is used to simply display the elevator’s operating status and to enable internal communication with the elevator car. The main areas of interaction between elevators and building automation systems are the following three: (1) Elevators receive signals from fire control centers; they return to their base stations in case of a fire, and fire elevators have functions specific for use in firefighting. (2) Cameras are installed inside the elevator car, and the video signals (sometimes including audio signals) are sent to the security center, where the conditions inside the car are displayed on monitors. In some cases, a device that generates floor number indicators for the elevator is also shown on the monitors, to assist security personnel in dealing with elevator failures or criminal activities. (3) The elevator is equipped with a speaker that can broadcast content from the public announcement system or switch to an emergency announcement. Furthermore, in some important locations, elevators are also included as part of the access control system; card readers are usually installed at the entrance to the elevator lobby or inside the elevator, and these readers are used to identify passengers, thereby determining whether the elevator should operate or at which floor it should stop. In summary, our country is currently at a relatively low level in terms of the integration and application of elevator monitoring systems with advanced low-voltage technologies. 2 Applications and Development Trends of Elevator Monitoring Technology. Elevator monitoring is part of the building automation management system in intelligent buildings; therefore, advancements in elevator monitoring technology also constitute a fundamental factor in improving the level of such management systems. Elevator monitoring technology must be considered from two aspects: system design and individual application level, whether in terms of long-term or short-term goals. From the perspective of system design, the ideal long-term goal for elevator monitoring is to move towards a model of centralized management at the societal level, or at least at the regional level. The advantage of this approach is that it allows for the standardization of the quality of products and services provided by various elevator manufacturers, installers, and property (maintenance) service providers. This enables these suppliers to compete under fair, equitable, and transparent conditions, thereby improving the quality of their products and services and leading to increased overall efficiency and reduced costs. Ultimately, to provide customers with a cheap, safe, and comfortable elevator service. To achieve this goal, it is necessary for the **or relevant department to standardize the standards and quality of products and services provided by various suppliers. Given the current state of elevators in our country, it is necessary to standardize, from a technical perspective, the provision of a unified communication interface and communication protocol by various elevator suppliers. Technically speaking, this should not be a problem; currently, all major elevator manufacturers are able to ensure that, even if the programs inside the elevator are not affected by external interference, communication can still take place using a standardized protocol, allowing the elevator’s operating status to be transmitted externally or control commands from outside to be received. Given the conditions in our country, there is still a long way to go before elevator monitoring can be managed on a societal scale. The main obstacles lie in two aspects: first, the current property management model in our country operates on a closed, limited scale, and does not consider elevator monitoring as a need or requirement for societal-scale management; second, there is no unified communication protocol among the different brands of elevators available in our country, and there are no standardized specifications for the software and hardware required for low-voltage monitoring – in many cases, such components are not even included as standard features. If social-integrated management is to be implemented, the amount of work required to modify existing elevators would be substantial. Therefore, it can be said that the time is not yet ripe for social-integrated management of elevator monitoring. Yet, the use of high-tech solutions based on low-voltage control for elevator monitoring represents the trend for the future, and achieving regional or societal integrated management of elevator monitoring is not something that is far off in China either. For this reason, the author believes that it is necessary to urge **regulatory authorities and all stakeholders in the elevator industry to pay attention to research on the development directions of elevator monitoring, and to carry out foundational work in various aspects such as standards and specifications, design and manufacturing, installation, and maintenance. Below, I will provide an example. Camera surveillance inside the elevator car. In China’s current elevator market, camera monitoring systems inside elevator cars are not considered by elevator suppliers as either a standard or optional feature of elevators; as a result, optimal solutions for such systems are generally not taken into account during the design or manufacturing process, and they are often added temporarily based on the requirements of the clients. Some manufacturers of low-voltage equipment carry out this task after the elevator has been installed, while others entrust elevator installers to do it during the installation process. Due to the lack of effective guidelines to regulate the actions of all parties involved, the results are often unsatisfactory, as reflected in the following aspects. (1) The choice of camera is not ideal; when installing surveillance cameras in elevator cars, it is necessary to consider compatibility with the overall decoration of the car, as well as aesthetics and concealment. Therefore, it is advisable to use dome-shaped cameras designed specifically for elevators and mounted on the ceiling. Such cameras, equipped with wide-angle lenses, are small in size, have an attractive design, and offer good concealment. However, most elevator cars are equipped with ordinary gun-type cameras; some have the camera installed directly on the top of the car, while in others a hole is made in the top of the car to expose the lens. Due to the improper selection of cameras, the decorated elevator ceiling appears very unharmonious; an inappropriate installation via openings only makes things worse. (2) The selection of video cables for cameras is inappropriate; for elevator surveillance, soft video cables designed specifically for elevators should be used. These cables ensure impedance matching, deliver good video quality, and have a long service life. Additionally, the video cables as well as the power cords for cameras should be incorporated into the accompanying cables, to prevent damage to them during elevator operation, thereby enhancing reliability and service life. In many existing projects, ordinary video cables are used; these cables tend to break, which shortens their lifespan and results in poor video quality. What’s more, using a radio frequency cable instead of a video cable obviously doesn’t work. In summary, it is necessary first to conduct research and establish standards for various aspects related to elevator monitoring, such as communication technologies, integrated cabling, security equipment, and automatic control technologies. By drawing on standards from other low-voltage electrical industries or by formulating specific standards for elevators one by one, it is possible to achieve uniformity and improve the quality of individual applications in elevator monitoring, thereby creating the conditions needed to standardize the system design for elevator monitoring. Thus, elevator monitoring design is further integrated as part of the overall elevator design, and it becomes part of the building automation design. At the same time, standards and quality in elevator manufacturing, installation, and maintenance have also been improved accordingly. This has led to the serialization and standardization of elevator monitoring devices; by then, such devices will become standard or optional components of elevator equipment, featuring uniform standards and interfaces. As a result, it will be easy to implement regional and social management systems for elevator monitoring.