Smart Elevator Communication Solution

I. Overview of Smart Elevators

With economic development and the continuous expansion of urban scale, the number of high-rise residential buildings, hotels, and office buildings is constantly increasing. As a result, the number of elevators serving as vertical transportation means is also growing, with the total number of elevators nationwide now exceeding 1.5 million. While elevators bring convenience to people entering and exiting high-rise buildings, elevator failures causing casualties and economic losses are also increasing. Therefore, how to effectively monitor the safe operation of elevators and promptly eliminate various hidden elevator faults has become an urgent issue for property managers, elevator maintenance companies, and regulatory authorities.

Elevators are an indispensable part of our daily lives. The safe and reliable operation of elevators and their scientific management are the focus of attention for the government, manufacturers, maintenance units, and the general public, and are also the shared responsibility of relevant organizations and regulatory bodies. Data released by the Special Equipment Safety Supervision Bureau of the General Administration of Quality Supervision, Inspection and Quarantine shows that in recent years, elevator accidents and failures have remained at a high incidence rate: in 2007, there were 33 elevator accidents, accounting for 13% of the total special equipment safety accidents, of which 22 were fatal elevator accidents, causing 25 deaths and 10 serious injuries; in 2008, there were 38 elevator accidents; in 2010, there were 44 recorded serious elevator accidents in China alone, resulting in 43 deaths. The well-known "Heinrich's Law" in the safety field states that behind every serious accident, there must be 29 minor accidents, 300 near-miss incidents, and 1,000 potential hazards.

With the continuous development of computer and network technologies, the increasing intelligence of elevators, and especially the deepening application of IoT technology in the industry, the necessary conditions for the implementation of intelligent elevator management systems have been provided.

Functional Description of the Smart Elevator Integrated Solution

1. Fault Alarm:

This includes alarms detected by the elevator system and manual alarms triggered by elevator passengers pressing the alarm button. It provides elevator maintenance personnel with the scope of elevator faults, thereby shortening maintenance time, while also providing statistical data on elevator fault occurrences and a basis for setting pre-alarm parameters.

2. Resource Location Function:

It can quickly locate the faulty elevator on the system map, allocate maintenance resources from the nearest location, and know the exact position of the faulty elevator at the first moment, maximizing time for rescue and troubleshooting.

3. Operation Status Monitoring Function:

Elevator operation status; elevator running direction; elevator arrival floor; elevator fault status; elevator leveling condition, and door operator working status. Based on the elevator operation status display, the system accurately grasps the actual elevator running time and the usage count of wear parts, providing effective values for data statistics; when an elevator fault occurs, it provides accurate information to maintenance personnel.

4. Elevator Archive and Maintenance Resource Archive Management Function:

Hierarchical remote viewing of various elevator data, statistics, and analysis functions:

Statistics on fault types and quantities, maintenance response time, actual elevator operation time, wear part usage count, and maintenance costs. Based on each set of data, analysis and storage are conducted to achieve the purpose of early warning of elevator faults.

5. Resource Dynamic Dispatch Function:

Real-time updates on the map of elevator maintenance personnel and maintenance tool kit configurations, with the nearest maintenance personnel dispatched when an alarm occurs. It also has an attendance function to improve the service quality of maintenance personnel. The system can display the elevator maintenance personnel, maintenance time, and time spent, thereby improving work efficiency.

This includes maintenance personnel viewing elevator archives, warehouse spare parts, and contacting the command center via mobile terminals!

6. Emergency Command Function:

When an elevator fault occurs, passengers press the alarm intercom button, or the elevator system automatically alarms. The dispatch center personnel's screen automatically pops up the elevator archive, including the manufacturer, maintenance unit, maintenance records, geographic location, fault location, fault type, etc. The nearest maintenance personnel are contacted to arrive promptly, and maintenance spare parts are also dispatched in a timely manner from the appropriate warehouse, until the maintenance personnel are guided to the elevator and contact with the passengers is established. After handling is completed, relevant records are updated. Multiple communication means such as wireless intercom, mobile phones, fixed telephones, and elevator intercoms are fully utilized, with one-click connection to maintenance personnel and management personnel to shorten maintenance response time. At the same time, professional dispatch personnel can also understand the condition of passengers inside the elevator in real time, promptly provide safety protection knowledge to passengers in the elevator, and offer first-time psychological comfort.

The emergency linkage command system, in response to on-site emergencies, first establishes stable contact with the site in real time, including reliable communication with WiFi, 3G, and wired transmission methods as backups for each other, establishing a remote communication network to facilitate the emergency command center in fully understanding the development of the on-site situation, and to facilitate expert analysis and diagnosis and leadership decision-making at the command center. The system can provide various historical data such as elevator fault statistics, maintenance data, and elevator operation data, provided to the command center in multiple forms including data, voice, images, video, and text, offering effective and reliable decision-making data for on-site command. In addition, with fast network communication, it can uniformly command multi-party joint rescue and leverage the advantages of all parties. It is reliably compatible with existing command systems of relevant departments such as the Safety Supervision Bureau and the Quality Supervision Bureau, achieving information sharing.

7. Public Information Disclosure, Advertising Channel, and Convenience Services for Society:

Based on the elevator IoT monitoring system, a new community public information platform is established, providing multi-faceted application services, including information service platforms, e-commerce, and other applications. The platform consists of multiple parts, including a content publishing management center, multimedia publishing servers, multimedia terminals, and wireless network platforms. Through this platform, the government, property management, and other departments can publish elevator safety emergency information, public service information, and other related service content, establishing a vertically managed information channel for the government and relevant units to better serve the public.

Various government incentive and support policies have effectively driven the development of the IoT industry, promoted technological innovation in the IoT industry, and expanded the industry chain. Elevator IoT improves the safe operation level of elevators, saving labor costs for elevator regulatory units and maintenance units, and improving work efficiency. Research on elevator IoT has achieved remarkable results. The application of elevator IoT not only ensures the safety of life and property of elevator passengers but also effectively promotes the construction of smart cities.

II. Current Status of Smart Elevators

On the large screen wall of the Shanghai Mitsubishi User Service Center, from the China map zoomed into the Shanghai map, and then to the Changning District and the Free Trade Pilot Zone as pilot areas, the distribution of "smart elevators" is fully visualized. They bear the responsibility of the national-level enterprise technology center and have developed this elevator IoT network, with currently 40,000 elevators connected to the network. On this basis, the center also collaborates with the Municipal Quality Supervision Bureau and the 110 emergency response system, serving as the Shanghai Elevator Emergency Response Center to undertake the city-wide emergency rescue command work.

Data released by the Guangzhou Municipal Quality and Technical Supervision Bureau on July 16, 2014, shows that in the first half of 2014, Guangzhou handled 2,562 elevator entrapment incidents and 1,386 faults, rescuing 6,947 trapped persons. Among them, 70% of elevator faults in June occurred in residential communities.

There are over 70,000 elevators in use in the Hangzhou area, with 3,961 elevators connected to the network, mainly in newly built communities and elevators in densely populated places such as shopping malls, hotels, hospitals, and schools. The "Implementation Opinions on Strengthening Elevator Safety Work in Hangzhou" clearly states that elevators in newly built residential communities must be equipped with elevator IoT devices. Governments at all levels should establish funding mechanisms for major repairs, renovations, and replacements of old elevators, simplify procedures for applying for the use of special maintenance funds for properties, and promote the elevator IoT renovation work.

Currently, more than 90% of elevator companies' after-sales maintenance and inspection methods still rely on a pen and a piece of paper, and the information recorded on paper cannot be quickly queried, retrieved, or analyzed. Many times, routine maintenance is often just a superficial "checkmark and going through the motions." What accompanies the elevator IoT is precisely maintenance service management based on mobile terminals. Maintenance personnel all hold terminal devices similar to mobile phones, receiving "work packages" dispatched by the system on their handheld terminals. Whether they arrive at the maintenance site, how much time they spend, and whether they operate according to procedure are all recorded one by one. Even when performing "surgery" on a certain part, the smart terminal supports photo upload, "live broadcasting" the process to central control personnel until the task is fully completed.

The elevator real-time monitoring platform, maintenance monitoring platform, equipment traceability platform, and emergency command platform are integrated into one, with all this information consolidated on the same platform, enabling first-time information acquisition, first-time command issuance, first-time rescue implementation, and first-time investigation and handling when elevators experience abnormalities or faults. It also allows real-time tracking of the maintenance status of elevator maintenance units, enabling remote review of elevator operation status and health conditions at any time without leaving the office.

For common faults such as elevator doors being stuck, sensors inside the door can monitor the resistance of door closing. If the normal door closing current is only 1 ampere, but the current frequently reaches 1.5 amperes before a fault occurs, it is highly likely that there are foreign objects in the elevator door rollers or guide rails. It is reported that when elevator doors are blocked by small debris, the resistance to opening and closing increases, and the "smart elevator" can not only predict faults in advance but also precisely determine which floor's elevator door is encountering obstacles.

As long as an elevator fault occurs, the sensors sense the elevator status and send a danger signal to the elevator safety operation monitoring platform. At the same time, based on different corresponding levels, it notifies maintenance units, rescue units, property management companies, and even emergency centers and other response entities.

Currently, multiple cities have opened 96333 elevator emergency command centers specifically to handle sudden elevator accidents. Some elevators are equipped with operation status monitoring and automatic alarm systems. Once an elevator operation problem occurs, it automatically sends an alarm to the backend platform for assistance. Automatic alarm and risk warning are the greatest benefits achieved after applying IoT technology.

The responsible entities for elevators have now been clearly defined:

1. The elevator user manager bears primary responsibility. For newly installed elevators not yet handed over, the project construction unit is the elevator user manager;

2. When commissioning elevator maintenance enterprises to carry out maintenance, the signed contract should clearly stipulate that the elevator maintenance enterprise bears responsibility for elevator maintenance quality and operational safety;

The accelerated development of the smart economy in various regions, as well as the deepening of elevator safety management regulations, will provide stronger policy guarantees and financial support for elevator networking.

When an elevator is in operation, hundreds or even thousands of components work together in coordination. In the past, elevators relied solely on wire connections. Once a problem occurred, maintenance personnel had to go to the site to test item by item. After emergency repairs, the elevator would temporarily operate normally, but if hidden safety hazards remained, they were very difficult to detect. If elevators are equipped with a "chip" — sensors and chips — with the help of IoT technology, elevators become "intelligent." "Smart elevators" can monitor dozens of status parameters. Once an elevator has a problem, the "map" large screen at the remote center displays it immediately, completing remote fault diagnosis at the first moment, allowing maintenance personnel to quickly understand the elevator's "condition" without leaving the office and to perform on-site repairs with "the right medicine for the symptom."

In addition to quickly detecting faults, it is even "smarter" in that it can transmit its health status to the service center in real time, including daily elevator health indicators such as the number of door openings and closings and the number of steel wire rope ascents and descents. Through "big data" analysis, it helps technical personnel fully understand the recent health trends of the elevator, when certain components should be replaced, and so on. The relevant IoT chips and modules can be directly embedded in newly installed elevators; for elevators already in use, they can also be conveniently retrofitted.

As a special piece of equipment related to the safety of thousands of households, elevator usage and maintenance are similar to automobiles. Within a service life of 15-20 years, the "maintenance journey" of the entire life cycle begins on the first day of "operation." Each elevator is maintained twice a month, which is the legally mandated "physical examination" rhythm for elevators in China. The "Smart Elevator Network," based on IoT technology systems, allows elevators to "speak up and report errors." Maintenance personnel holding mobile terminals can stay almost synchronized with the central remote monitoring, learning about elevator faults in their jurisdiction communities at the first moment and receiving "work packages" dispatched by the system. "The remote monitoring center is also linked with the 110 emergency response system. Once an accident occurs, rapid emergency response is implemented, and the remote monitoring center simultaneously supervises whether safety procedures at the elevator maintenance site are implemented one by one."

It is understood that Shanghai has become the city with the largest number of elevators in the world, with a total of 175,000 elevators in use, among which "operating with defects" is very common. As special equipment, according to legal requirements, each elevator should be maintained twice a month, but not many actually achieve this. Many elevators are still "not maintained until they break down"; even routine inspections are just "a pen and a piece of paper" going through the motions. Over time, passenger safety is difficult to guarantee.

The introduction of IoT technology may improve this situation. According to the operating principle of smart elevators currently in use: the elevator remote monitoring system can connect directly to the elevator control system through a dedicated interface, enabling remote monitoring of elevator fault operation status. Dedicated personnel can monitor the operation status of each elevator in real time through the computer system center map, regularly upload daily operation data through the monitoring system, and prevent hidden hazards from occurring as early as possible.

III. Smart Elevator Communication Solution

Currently, the elevator alarm and maintenance system uses a twisted-pair-based five-party intercom system, with transmission distance limited to 1–2 km. Long-distance transmission relies on GSM, which can only carry voice and, in a few cases, some status data. Since long-distance transmission is based on IP and fiber optics, there are very few fiber- and IP-based elevator intercom solutions on the market. Some organizations have developed their own IP-based intercom systems, but these cannot fully utilize the existing five-party intercom system already installed in elevators, resulting in waste and high costs.

[Beijing Raytrans Company](

The products are divided into fiber-optic transmission-based intercom systems, including five-party intercom optical multiplexers with transmission capacities ranging from 2 to 300 elevator channels. In addition to intercom voice, they also provide RS232/RS485 interfaces for connecting to elevator detection output ports. They can also provide 100M or 1000M Ethernet interfaces for connecting video surveillance cameras on elevators.

Fiber optics can extend the transmission distance of the five-party intercom system, but for larger coverage areas (such as an entire city), an IP network-based intercom system is required. Typically, bandwidth is leased from the three major telecom operators or cable TV operators, and VPN tunnels are established, connecting all monitored elevators in the city as an IoT network interconnected through a dedicated IP network.

1. Fiber-optic-based elevator five-party intercom

Multiple physically isolated Ethernet channels can also be provided, which not only meet surveillance requirements but can also be leased for value-added services such as advertising playback and WIFI provision.

Community five-party intercom central management system diagram based on fiber-optic transmission

2. IP-based elevator five-party intercom and smart elevator management system

Within the leased Ethernet bandwidth, the system can provide elevator five-party intercom, elevator operation status monitoring, elevator-adjacent advertising access, and elevator-adjacent WIFI access, offering wireless network services to passengers and maintenance personnel. It can also connect to the smart elevator management system via VPN software installed over the public wireless network, enabling real-time contact with various maintenance centers and dispatch of all networked maintenance personnel. The location information of all maintenance personnel is transmitted in real time to the dispatch center via their mobile phones, and the location and cargo information of all parts delivery vehicles are also sent to the dispatch center in real time.