The internal communication of this project includes TELEPHONE SYSTEM and PUBLIC ADDRESS SYSTEM. The Power System Communication include Optical system communication and PLC communication system.

Because there is no adequate information about the communication system, the proposed design is just elementary. Detailed proposals will be provided at the next stage of the project.

The whole communication system is designed and installed in accordance with the following codes and standards:

ITU-T  International Telecommunication Union-Telecommunication

IEC    International Electromechanical Commission

ISO    International Standard Organization

11.2.1 Telephone communication system

The system consists of PABX (Private Automatic Branch Exchange) and MDF (Main Distribution Frame), distribution terminal equipments, cable network and so on. It not only provides the communication among designated locations in the power plant, but also realizes the external communication with the local public telephone network. In the project, the system capacity of the PABX is 150 ports and can be expandable to 512 ports. The design of linking to the public telephone network will be not included.

11.2.2 Public address system

The public address system will be provided in this project. This system consisted of central exchange, power amplifier, station, loudspeaker and cable network. The system can accomplish two-way communication by the page/party function and spread message, alarm signal at the same time, and it is easy to find the shifting staff by the broadcasting function. In this system, it would provide about 30 stations (include loudspeakers).

20 sets of Walkie-Talkies will be supplied for moving communication in the power plant.

11.2.3 Distribution equipment and cable network

The cable network for the telephone communication system includes MDF, cable distribution cabinets, junction boxes, terminal boxes, telephone sockets, cables and wires.

The cable distribution boxes and junction boxes are arranged indoor or outdoor as required. Terminal boxes and telephone sockets are of wall types. Cables are laid along with electrical cable trench (tunnel and tray); in case electric cable trench is not available, cables are laid through tubes.

Communication cables consist of stranded conductor with diameter no less than 0.5mm, they are damp-proof, dust-proof, fire-proof, acid-proof, caustic-proof and non-spreading of fire.

11.2.4 Communication rooms

The communication rooms will be in the Office Building of the power plant and include communication equipment room, duty room and batteries room.

11.2.5 Communication power supply

The power for communication equipments would be supplied by two set of -48V DC power supply system and two banks of batteries.

There are one 110kV power transmission lines from the Thermal Gecelca 3 1×150MW Coal Fired Power Plant to opposite substation. As the local power communication network is unclear, the optical system communication and PLC system communication are just considered to communicate with the opposite substation. The optical and PLC equipments in the opposite substation would not be included in this design.

11.3.1 Optical system communication

The capacity of optical communication would be STM-4(622Mb/s) and equipped with STM-4 drop/insert multiplex equipment, PCM and so on. The optical system communication is used to transmit speech, line relay protection between the power plant and opposite substation.

11.3.2 PLC communication system

One PLC channels are arranged on power transmission line between the power plant and the opposite substation. The PLC communication system is backup channel for transmit speech and line relay protection signal. The PLC terminals, line traps and coupling devices are supplied.