What does weak current in hotels include? Should weak current in Beijing hotels be rewired and installed? All those things included?

Commonly used building weak current systems mainly include the following types:

(1) Telephone communication system

Realize telephone (including three types of fax machines, video phones etc.) communication function; star topology; using Category 3 (or above) unshielded twisted pair, and the frequency of the transmitted signal is within the audio range.

(2) Computer LAN system

Is the network foundation for office automation and various data transmissions; star topology; using Category 5 (or above) unshielded twisted pairs , transmit digital signals, the transmission rate can reach more than 100 Mb/s.

(3) Music/broadcasting system

Play music through speakers installed on-site (such as shopping malls, restaurants, guest rooms, corridors, etc.), and can conduct live broadcasts through microphones Broadcasting; multi-channel bus structure; transmits the constant voltage 120 V/120 Ω audio signal output by the power amplifier to drive the on-site loudspeaker to produce sound. The transmission line uses copper core insulated wires.

(4) Cable TV signal distribution system

Evenly distribute the cable TV signal to each user point in the building; use branches and distributors for signal distribution, in order to reduce signal distortion and attenuation, so that the signal quality of each user point meets the requirements stipulated in the specification. The wiring is a tree structure, and varies with the form of the building and the distribution of user points; 75 Ω radio frequency coaxial cables are used to transmit multiple radio frequency signals .

(5) Security monitoring system

Use cameras, anti-theft detectors and other equipment installed on site to monitor the entrances and exits of the building and some important places and alarm for abnormal situations, etc. ; The transmission of video signals adopts a star structure and uses video coaxial cables; the transmission of control signals adopts a bus structure and uses copper core insulated cables.

(6) Fire alarm system

This system consists of three parts: fire alarm and fire linkage system, fire broadcasting system, and fire intercom telephone system. The fire alarm and fire linkage system monitors the on-site situation through fire detectors, manual alarm devices, etc. set up throughout the building. When there is an alarm signal, based on the received signal and according to the preset program, the corresponding equipment to control the spread of fire. Its signal transmission adopts a multi-channel bus structure. However, for the transmission of linkage control signals of important fire protection equipment (such as fire pumps, sprinkler pumps, positive pressure fans, smoke exhaust fans, etc.), star-shaped transmission is sometimes used. Structure, signal transmission uses copper core insulated cables (some products require the use of twisted pairs). The fire broadcasting system is used to direct the safe evacuation of on-site personnel in the event of a fire. It adopts a multi-channel bus structure and uses copper-core insulated wires for signal transmission (this system can be used in conjunction with the music/broadcasting system). The fire alarm intercom telephone system is used to direct on-site firefighters to carry out fire-fighting work. It adopts two structures: star type and bus type, and shielded wires are used for signal transmission.

(7) Entrance and exit control system

Use computers, smart card door locks, card readers and other equipment to set, monitor, control and record the status of each entrance and exit to achieve building control Unified management of all entrances and exits of objects ensures building safety. Its topology and transmission media vary depending on the product.

(8) Parking lot charging management system

Through the induction coil installed under the entrance and exit ground, the entry and exit of vehicles are sensed, and the charging is realized through the manual/semi-automatic/fully automatic charging management system and control the opening and closing of electric railings, etc. The system wiring www.cnsps.net is limited to the entrances and exits of the building's parking lot. Each entrance and exit is controlled by a controller. The controller can work independently or be networked with the upper management computer. Its wiring structure and transmission media vary depending on the product. .

(9) Building automation system

Through various detection and execution devices connected to the on-site controller, various environmental parameters inside and outside the building and various equipment in the building (such as It detects, monitors and controls the working status of air conditioning, water supply and drainage, lighting, power supply and distribution, elevators and other equipment, and connects various on-site controllers through the computer network to reasonably allocate and manage the resources and equipment in the building to achieve comfort. , convenience, savings and reliability. So far, there is no international standard for building automation systems. The communication protocols used by products of different manufacturers are different, and the topologies and transmission media of their field buses and control buses are also different.

The following will give a brief introduction to LonWorks technology and BACnet technology, which are currently generally accepted and adopted by the international community. In addition, there are video conference systems, sound reinforcement systems, patrol systems, building intercom systems, three-meter (water, electricity, gas meters) automatic meter reading systems, etc. Buildings with different functions require different weak current systems.