Two-bus multi-loop fire-fighting broadcasting system, and implementation method and device thereof

Abstract

The invention relates to a two-bus multi-loop fire-fighting broadcasting system which comprises a fire alarm controller, a fire-fighting emergency broadcasting host and an audio power amplifier whichare in communication connection in sequence. A plurality of PLC modems A are arranged on the audio power amplifier. The PLC modems A are in communication connection with one or more paths of addressing loudspeakers. The PLC modems A are in communication connection with PLC modems B on the addressing loudspeakers. The addressing loudspeakers are connected with one or more loudspeakers. By adoptingthe technical scheme of the invention, the limitation on the number of addressing loudspeakers can be broken through, the condition of cross interference does not occur when the two PLC communicationcircuits and the loop connecting lines thereof are close to each other, and the communication stability is good.

Description

technical field [0001] The present invention relates to the technical field of fire broadcasting, and more specifically, to a two-bus multi-loop fire broadcasting system, an implementation method and a device. Background technique [0002] The fire broadcasting system is also called the emergency broadcasting system. It is an important equipment for fire escape, evacuation and fire fighting command, and plays an extremely important role in the entire fire control management system. When a fire occurs, the fire alarm system sends emergency broadcast instructions to the fire broadcast system, and the fire broadcast system immediately enters the emergency broadcast state, and sends out the emergency broadcast signal through the audio source device. After power amplification, the addressing speaker switches to the broadcast designated area Speakers for emergency broadcasting. [0003] A general fire broadcasting system is mainly composed of a fire alarm controller (linkage type...

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Problems solved by technology

[0003] A general fire broadcasting system is mainly composed of a fire alarm controller (linkage type), a fire broadcasting host, an audio power amplifier, a broadcasting area control panel, a broadcasting control module, and a speaker. figure 1 As shown, it is basically based on narrowband power carrier communication technology (PLC), and 120V audio power, DC24V power supply, partition control information and status information of field devices (addressed speakers and non-addressed speakers) are simultaneously transmitted on the bus; This method has the following problems: 1. Low communication efficiency: Although PLC communication can support 255 nodes per loop, because of the limited communication bandwidth of narrowband PLC, the communication time of each point is longer. According to different algorithms, a basic package (including The frame header and data total 16 bytes) and the communication time is between 120ms and 170ms. In order to meet the real-time requirements of GB16806 in the fire protection industry and actual engineering control, the number of addressing speakers carried by each PLC loop is limited, which cannot meet the needs of medium and large Requirements of the project; the load capacity of the 2 loops is limited: the power supply of the addressing speaker control circuit is generally DC24V, and each addressing speaker is equipped with a PLC communication module, and the maximum power consumption of each PLC communication module is about 2W. The power consumption is about 150mW. Calculated according to the loop impedance of 40Ω in engineering applications and the terminal working voltage not less than 18V, each PLC loop can only carry about 30 addressed speakers, which cannot meet the needs of medium and large projects; there is cross interference between the 3 loops : In order to ensure the reliability of long-distance PLC communication and signal transmission, the detection sensitivity of PLC communication signals is generally set at the μV level. Each loop line will have communication confusion due to cross interference, and effective communication cannot be achieved.

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