【 Weak current College 】 fire radio and background music system integration design Essentials

Summary: fire broadcasting is the high-rise building and is equipped with centralized alarm or control center and alarm system of an essential system architecture. The background music is to give people to create a relaxed and happy shopping environment or lodging environment. Thus in the large shopping malls, hotels, hotel soundtrack has universal application. How to set the fire radio and background music system so that it meets the system requirements and economic reasonable and easy to manage, this article describes a scenario.
Keywords: fire radio background music system integration design
I. system constitute
Public broadcasting and cablecasting, also known as PA (PublicAddress) broadcasts. Public broadcasting in public places, usually play background music, and automatically back to belt loop; fire, as accidents, commanding the evacuation. Broadcast audio system usually consists of four major components: program source device, signal amplification and processing equipment, transmission lines and speaker system.
Program source equipment → zoom in and processing equipment ¡ú transmission line → field sound system
1. program source device:
Program sources typically have radio (FM, am), General records, compact discs (CD) and cassettes, etc., a corresponding program source device with FM/AM tuners, record player, CD player and recording deck, etc. In addition, there is a microphone (MIC), TV sound (including a DVD player, video recorder, CD player and satellite TV's sound), electronic musical instruments, etc. Usually you can provide the user with three to five sets of background music. 2, signal amplification and handling equipment:
Signal amplification and processing equipment including a mixer, preamplifier, power amplifier and a variety of controller and audio processing devices. This part of the device's main task is to signal amplification — — voltage amplifier and power amplification, followed by the signal of choice by selecting a switch to select the required program source signal. 调音台和前置放大器作用或地位相似(当然调音台的功能和性能指标更高)，它们的基本功能是完成信号的选择和前置放大，此外还担负对重放声音的音色、音量和音响效果进行各种调整和控制的任务。 有时为了更好地进行频率均衡和音色美化，还另外单独接入均衡器。 总之，这部分是整个音响系统的控制中心。 功率放大器则将前置放大器或调音台送来的信号进行功率放大，通过传输线路去推动扬声器放声。
3、传输线路：
For Hall, theatre, dance halls, karaoke, etc, because of the power amplifier of proximity, they generally use low resistance and high current direct feed means that the transmission line is referred to as a loudspeaker cable requirements section larger stroke, because this kind of system to replay sound quality requirements are higher, so commonly used dedicated loudspeaker cable. For the public broadcasting system and room broadcast system, due to the service area, long distance, in order to reduce the losses caused by the transmission lines, often requires a high-voltage transmission mode, because the transport current in smaller, less demanding on the transmission line. This method is commonly referred to as the constant pressure of transmission. In addition, the rooms broadcasting system, there is a hotel of CATV (master antenna television system) common carrier transmission system, and the use of CATV transmission line of video cable, but you cannot use generic audio transmission.
4 speaker system:
Speaker system, also known as stereo or speakers. Its role is to convert the audio energy corresponding sound energy. Due to the sound from the audio directly from dark to the human ear, so its performance indicators will affect the quality of the playback system. Speakers typically consists of speakers, divider, box, etc. Classification in accordance with the case of forms, speakers can be divided into closed speaker, inverted phase-speakers, loudspeaker, acoustic, drum several columns. By combining a fractional number of speakers, can be divided into two frequency speaker, three frequency speakers, four frequency speakers. Classification in accordance with the purpose, can be divided into high-fidelity loudspeakers, listening with speakers, public broadcasting (sound reinforcement) loudspeakers and other specialized applications (such as fire protection, waterproofing, alarm, etc.) of the speakers. From the body, usually closed and inverted phase-speakers. Sound column is appropriate for the venue sound reinforcement systems. But in performance, to listen to the most demanding loudspeakers.
Second, the system design
1. for the hotel corridors, hallway, Elevator, shopping malls and other public areas and hotel rooms use the constant pressure of transmission. Transmission line using twisted pair.
2, Office, living room, rooms, etc. can be 1-2W speakers. Generally each one.
3, corridor, entrance hall and public places of background music, business, such as speakers can be broadcast 3-5W; corridor a speaker can cover 6-8 metres in length; public activity places a speaker can cover 40-60 square meters.
4, PA choice usually each partition of a table, its rated capacity at rated load impedance value is less than or equal to the total impedance all speakers in parallel. The Z0 ≤ ZL/n type, Z0 represents the selected the impedance of the amplifier; ZL said speaker impedance; n indicates the number of speakers. Of course, in practice you should also consider the speakers at the opening of the coefficient.
Third, the system features
In line with national standards GB50116 People's Republic of China-98 the automatic fire alarm system design specifications "in relation to the relevant provisions of the fire broadcasting, namely, the" fire emergency broadcasting and public broadcasting and should meet the following requirements:
1, the provisions of the fire code 5431 should be can't fire control room will fire evacuation level for the speakers and to public broadcasting amplifiers force fire emergency broadcast status.
2, the provisions regulating 5432 should fire control room monitor for fire emergency broadcast of amplifiers for operation and should be opened with remote control and microphone audio amplifiers.
3. specification provided bedside control cabinet 5433 offers services of music radio speakers, should have the fire emergency broadcasting function.
4. specification requirements should be set 5434 fire emergency broadcast alternate amplifiers, its capacity should not beLess than the required scope simulcasting of fire emergency radio speakers a maximum capacity of 15 times the sum.
5, will fire emergency broadcasting and background music, room bedside Cabinet audio collection as a whole, i.e. the public a load network, shall not be required to repeat the investment, you can save money.
6. collection of broadcasting sound system should have two main functions; usually for the broadcast area provides background music, room broadcast or paging service broadcasting; fires provide fire alarm fire emergency broadcast, broadcasting system has precedence.
7. public play background music sources by broadcasting room unified control choice; in-room bed broadcast content control by the guests themselves, and allowed to select the volume, open or closed. All of these, shall not preclude enforcement of fire into the broadcast signal.
8, overall system load according to the building structure or business requirements partition control, you can adjust the volume, open or closed. Fires not only could force the starting area fire emergency signal, and according to their fire codes and adjacent areas (or upper and lower layers) can be automatically recognized and starting a fire emergency broadcast signals.
9, fire emergency broadcast signal is switched on, automatically recording, providing on-site live record, to sum up the experience.
IV. system principle (to * ** Center)
This engineering fire control rooms and control system with PA broadcast room; fire broadcasting by a power amplifier that can meet the requirements of broadcasting is divided into three districts; PA, and three amplifier.
Part 1, guest rooms
Room broadcast programming choice, volume control switch and the speakers are installed in the nightstand speakers choose 5-65-inch tray-speakers. Broadcast audio system typically provides three sets of programs to choose to listen to for guest rooms, but also fire fire control signal and broadcast signal sent separately to each room, in room music wiring box installation relays. Normally, the relay is not receiving power normally closed contact closure and connects with the PA system for guests choose to enjoy the background music; fire emergency fire control line have 24V electrical power to the relay, the normally closed contact to disconnect, that is disconnected from the speakers and the PA system; it normally open contact closed, that is, the speakers and fire broadcasting system is switched on. Visible, no matter how PA system is in a State that is able to guarantee the emergency and fire protection system is switched on, and fire emergency radio broadcast.
2. the public area
Because the two systems of control centres and in a room (if not in the room, proximity or you can use the following system), the two systems of wires are short, you can easily broadcast signal will fire and fire control signal sent to the PA system. For the public area within the background music control in radio control center. Under normal circumstances, the relay is not receiving power normally closed contact closure and connects with the PA system; public areas you can enjoy the soundtrack, in emergency situations to have fire control line, the relay 24V electrical power, the normally closed contact to disconnect, that is, and PA system; it normally open contact closed, that is connected with the broadcasting system, the emergency radio broadcast on fire. The figure shows: public area has three partitions, each partition a single amplifier, radio one amplifier to use relay normally open contacts, normally closed contacts enable system normally play background music: in case of emergency fire emergency radio broadcast. Even more partitions are the same for the above functionality. If certain public areas in the scene on the background music for control, that can on-the-spot control switch and retro relay between the speakers; and access fire control line and fire broadcast line, the same can implement these features. Meet user's requirements.
5. Summary
Background music and broadcasting of integrated forms also a lot, but these systems adapt to any fire Eagle and background music equipment manufacturers of products that have structure flexible, easy to use, functional and reliable, wide application.