What does it mean to weak electricity?

What does strong electricity mean?

The concept of strong electricity is generally not related to the specific limits of voltage and current.

People in the electronic world are accustomed to two parts: strong electricity (electricity) and weak electricity (information). The two are related and different. Generally speaking, the object of high-power processing is energy (electricity), which is characterized by high voltage, large current, high power and low frequency. The main considerations are to reduce losses, improve efficiency, and weak electricity. The processing object is mainly information, that is, the transmission and control of information, which is characterized by low voltage, small current, low power and high frequency. The main consideration is the effect of information transmission, such as the fidelity, speed and breadth of information transmission. ,reliability. In general, weak current projects include television engineering, communications engineering, fire engineering, security engineering, imaging engineering, etc., and integrated wiring engineering for the above projects. Weak electricity is for strong electricity. Strong electricity = (380/220), high voltage regardless.

In the power system, the voltage below 36v is called the safety voltage, the voltage below 3kv is called the low voltage, the voltage above 3kv is called the high voltage, and the line directly supplying the power to the user is called the distribution line. For example, the user voltage is 380/220v. It is called the low-voltage distribution line, which is the strong electricity mentioned in the home decoration (because it is the highest voltage used by the family). Strong power generally means that the AC voltage is above 24V. Such as electric lights, sockets, etc. in the home, the voltage is 110V~220V. Household electrical appliances such as lighting fixtures, electric water heaters, heaters, refrigerators, televisions, air conditioners, and audio equipment are all strong electrical equipment. The intelligent system is a comprehensive system composed of construction equipment monitoring system, security defense system, communication network system, information network system, fire automatic alarm and fire linkage, etc., with the purpose of centralized monitoring, control and management; various data collection in the family. Control, management, and communication control or network systems are called intelligent lines (that is, weak electricity in home decoration). Weak current generally refers to DC circuits or audio, video lines, network lines, telephone lines, and the DC voltage is generally within 24V. The electrical input of telephones, computers, and televisions in household electrical appliances (cable television lines) and audio equipment (output lines) are all weak electrical equipment.

What does weak electricity mean?

Weak current generally refers to DC circuits or audio, video lines, network lines, telephone lines, and the DC voltage is generally within 32V. The electrical input of the telephone, computer, and television in the household appliances (cable TV line) and audio equipment (output line) are all weak electrical equipment.

There are two main types of weak electricity in buildings: one is the nationally specified safe voltage level and the low voltage electric energy such as the control weak current voltage. There are AC and DC points, such as 24V DC control power supply or emergency lighting standby power supply. The other type is information sources that contain information such as voice, images, and data, such as telephone, television, and computer information.

narrow sense

In the narrow sense, building weak electricity mainly refers to: security (monitoring, perimeter alarm, parking lot), fire protection (electrical part), building control, network cabling and audio system, etc.

The difference with strong electricity

Conceptually, strong and weak electricity are generally easy to distinguish. The main difference is the difference in use. Strong electricity is used as a kind of power source, and weak electricity is used for information transmission. They have roughly the following differences:

Different communication frequency

The frequency of strong electricity is generally 50 Hz (hertz), which is called "power frequency", which means the frequency of industrial electricity: the frequency of weak electricity is often high frequency or ultra high frequency, measured in KHz (kilohertz) and MHz (megahertz).

Different transmission methods

Strong power is transmitted on transmission lines, and weak power transmission is divided between wired and wireless. The radio is transmitted by electromagnetic waves.

Different power, voltage and current

classification

There are two main types of weak current in buildings: one is the low voltage electric energy such as the safety voltage level and control voltage specified by the state, and there are AC and DC points, such as 24V DC control power supply or emergency lighting standby power supply. The other type is information sources that contain information such as voice, images, and data, such as telephone, television, and computer information. The intelligent system is a comprehensive system composed of construction equipment monitoring system, security defense system, communication network system, information network system, fire automatic alarm and fire linkage, etc., with the purpose of centralized monitoring, control and management; various data collection in the family. Control, management, and communication control or network systems are called intelligent lines (that is, weak electricity in home decoration). Weak current generally refers to DC circuits or audio, video lines, network lines, telephone lines, and the DC voltage is generally within 24V. The electrical input of telephones, computers, and televisions in household electrical appliances (cable television lines) and audio equipment (output lines) are all weak electrical equipment.

What does weak current system mean?

The weak electricity system of intelligent buildings is the basic weak member of the intelligent group in intelligent buildings, and also a key component of intelligent buildings, and is the main object of the daily work of building electrical professionals. The weak electricity design before the 1970s only had telephone and broadcast design. After the 1980s, fire alarm and linkage control, shared antenna, security surveillance, and air conditioning DDC control were added to its content. The design content of the weak current design is expanding and expanding step by step, the technology is getting newer and newer, and the workload is getting bigger and bigger. The intelligent building weak current system generally includes the following sub-systems: Building Automation Management Subsystem (BAS), Fire Fighting Automatic Alarm Subsystem (FAS), Security Surveillance Subsystem (CCTV), Satellite Receiving and Cable TV Subsystem (CATV), Underground Garage Management Subsystem (CPS), Public Address and Emergency Broadcast Subsystem (PAS), Program Control Switch Subsystem (PABX), structured integrated wiring system (PDS) often includes the entrance and exit control subsystem and the anti-theft alarm subsystem in the building automation management subsystem. Each sub-system of the intelligent building provides monitoring and management of various types of electromechanical equipment for the building, creating a safe, healthy, comfortable and pleasant office environment for the building users, providing modern communication means and office conditions, satisfying A variety of user requirements for different environments and functions. Building Automation Management Subsystem (BAS) The Building Automation Management Subsystem is the core of the intelligent building weak system. Its high reliability is the cornerstone of the high reliability of the entire weak current system. Therefore, the BAS system adopts a three-level control method. The Fire Alarm System (FAS) uses intelligent smoke sensor and temperature sensor to intelligently sense smoke and heat, and provide corresponding analog values. Through advanced algorithms, the system can distinguish between real alarms and false alarms. . The exact location of the fire alarm and the nature of the alarm can be graphically displayed on the display of the system. After the fire alarm is confirmed, the system can automatically issue the corresponding fire emergency broadcast and fire linkage control, which lays a foundation for the safe evacuation of personnel and the effective and effective fire suppression. The Security Monitoring System (CCTV) consists of a CCTV surveillance system, access control, patrol system and anti-theft alarm system. Satellite receiving and cable television subsystem satellite receiving and cable television subsystem (CATV) is a basic system that is now widely installed. The satellite receiving system is a system that uses satellites to directly forward television signals. Its function is equivalent to a space forwarding station, which is the best way to solve the problem of TV coverage and high-quality transmission of television image signals. The cable television (common antenna) system uses a set of high-quality antennas to distribute TV signals to each user of the television system in a wired manner. It has two-way communication, videophone, graphic transmission, and can be networked with a home computer terminal. The underground garage management system (CPS) is based on the computer network and is equipped with various devices necessary for modern parking lots such as invoice/checking machine, automatic fence machine, vehicle induction coil, toll machine, etc. The system can be fully or semi-automatically managed. Large mode action. The Public Address System (PAS) is mainly used in shopping malls, business centers, lobby, restaurants, public walkways, etc. in the building. It can provide FM, AM broadcast programs, dual-card playback signals, CD player signals and microphone signals. The device can optionally select any of the above-mentioned sound sources, adjust the volume to an appropriate level through the volume control circuit, and output to a given area broadcast via the area selector. When there is a fire alarm signal, the system will automatically turn off the public broadcast, and automatically switch the fire layer and its upper and lower layers to the emergency broadcast. If necessary, you can also manually use the machine to carry out manual command. The Digital Programmable Telephone Switching System (PABX) provides sufficient voice capacity to ensure the use of all users in the building and leaves room for future expansion. The system can provide ISDN function through simple configuration interface, and can realize packet switching or other interfaces through optional X..25 interface to realize functions such as data communication. Through software setting, special virtual memory can be established in the system. Web function. The system has a variety of functions such as abbreviated dialing, calling special services, conference call, busy callback, call confidentiality, e-mail, voice mail, etc. The system also has daily automatic detection, diagnosis, positioning and automatic switching to standby when the host is seriously faulty. Machine function. The Structured Integrated Cabling System (PDS) is the "neural system" of the entire building, which enhances network applications such as video communication, fax and other video data, video conferencing and other video signals and data communications. The structured cabling system consists of six independent subsystems, namely the work area subsystem, the horizontal subsystem, the management subsystem, the vertical backbone subsystem, the equipment subsystem, and the building group subsystem.