Information and communication equipment: Basic knowledge of electrical equipment 6

Last time, I introduced the lighting equipment centered on lighting. In this final installment of this series, we will explain the basic knowledge of information and communication equipment. Information and communication equipment is light electrical equipment that handles electrical signals for transmitting information inside and outside the building. In addition to equipment that is indispensable to homes such as telephones, intercoms, and TV antennas, LAN that supports the information network in the building is also important information and communication equipment. Here, we will explain information and communication equipment in intelligent buildings and smart buildings, in addition to telephones that are conventionally used in ordinary houses. Finally, we will explain lightning protection equipment that plays an important role in protecting information and communication equipment.

Download technical materials now! (Login)

Table of contents

1. Telephone work

Telephone works are classified into outdoor works and indoor works. The outdoor work of the telephone is done by NTT until the telephone line is pulled into the building. Indoor works are telephone works as electrical equipment on the premises. For home phones, the phone line can be pulled in by connecting it to the building protector. A protector is a device that protects communication equipment from induced currents and high voltages generated by lightning strikes. If you wire from the protector and install a telephone terminal (modular jack) indoors, the telephone will be directly connected to the exchange at the central office. If you have one or two landlines in your home, this is all you need to do.

情報通信設備:電気設備の基礎知識6

For companies and facilities with dozens of phones, indoor work is required. First, install a private branch exchange (PBX) on the premises and connect to the telephone office. If you connect a telephone to this PBX, you can make calls on both the outside line and the extension line on each telephone. In this case, each phone is connected to the PBX, so if you have many phones or if you have multiple floors, you need to wire more.

Therefore, once the telephone wiring is consolidated on the terminal board. The terminal board is called the main distribution frame (MDF). Telephone lines will be distributed to each floor through MDF. As a result, wiring work can be done simply by connecting the telephone line (station line) and MDF to the PBX.

In addition, an intermediate distribution frame (IDF), which is a terminal board for relay, is installed on each floor to connect each telephone. Figure 1 shows the relationship between PBX, MDF, and IDF. Internet lines and optical lines can also be deployed in the building by connecting to MDF.

Figure 1: Telephone line lead-in (PBX, MDF, IDF wiring example)

In addition, various communication equipment such as on-site broadcasting equipment, TV common listening equipment, and intercom equipment for apartment buildings are installed in the building. Both are wired by relaying the terminal board such as IDF.

2. Information network

The first thing that is needed as an information network is a LAN (Local Area Network). A LAN enables data communication between a certain range of computers and various information devices. There are two types of LAN, wired and wireless. Generally, a standard called Ethernet is used for wired LAN and Wi-Fi (Wireless Fidelity) is used for wireless LAN. In addition, a standard called PLC (Power Line Communication), which uses power lines as signal lines, may be used.

Figure 2 shows the basic LAN configuration. Since a LAN consists of multiple devices, a hub is required to connect those devices as a network. In addition, it is said that communication with a LAN cable is up to about 100 m, and if it is longer than that, a router is used as a repeater.

Figure 2: Basic LAN configuration

The hub is used to connect devices in the LAN. The hub has many ports (connection ports) and is a common connection point for devices in the LAN, and is a concentrator located in the center. Those that have a switch function that connects only specific ports are called switching hubs.

Routers are used to connect to multiple networks. This device is required to connect an external network (WAN, Internet provider, etc.) to the LAN on the premises. A router acts as a gateway (translating a communication protocol). Also, relaying with a router means connecting LANs to each other. Various specifications and functions are combined in an actual repeater, and devices called repeaters, bridges, switches, etc. may be used.

3. Building automation

The continuation is being posted on the PDF for storage. Please download it from the following and have a look.

4. Lightning protection equipment

The continuation is being posted on the PDF for storage. Please download it from the following and have a look.