楼宇对讲系统设备原理及九大隐患

Principle and nine hidden dangers of building intercom system equipment

楼宇对讲系统是在各单元口安装防盗门，小区总控中心的管理员总机、楼宇出入口的对讲主机、电控锁、闭门器及用户家中的可视对讲分机通过专用网络组成。

The building intercom system is equipped with anti-theft doors at each unit entrance. The administrator's switchboard of the district general control center, the intercom host at the entrance and exit of the building, the electronic lock, the door closer and the visual intercom extension at the user's home are composed by a special network.

楼宇对讲系统是在各单元口安装防盗门，小区总控中心的管理员总机、楼宇出入口的对讲主机、电控锁、闭门器及用户家中的可视对讲分机通过专用网络组成。以实现访客与住户对讲，住户可遥控开启防盗门，各单元梯口访客再通过对讲主机呼叫住户，对方同意后方可进入楼内，从而限制了非法人员进入。同时，若住户在家发生抢劫或突发疾病，可通过该系统通知保安人员以得到及时的支援和处理。

The building intercom system is equipped with anti-theft doors at each unit entrance. The administrator's switchboard of the district general control center, the intercom host at the entrance and exit of the building, the electronic lock, the door closer and the visual intercom extension at the user's home are composed by a special network. In order to realize the intercommunication between visitors and households, the households can open the anti-theft door remotely, and the visitors at each elevator can call the households through the intercommunicating host, and the other party can enter the building only after they agree, thus restricting the entry of illegal persons. At the same time, if the household robbery or sudden illness occurs at home, security personnel can be notified through the system to receive timely support and treatment.

楼宇对讲系统需要以下设备：

Building intercom systems require the following equipment:

1)网络交换机：每个小区联网时必须配匹一个，它是整个小区网络资源管理器，对讲时选用哪个通道、数据通信仲裁、通信信号中继、协议变换等都要经过交换机处理。

1) Network Switch: Each cell must be equipped with one network resource manager, which channel, data communication arbitration, communication signal relay and protocol transformation should be processed by the switch.

2)联网器：分管理机(栋管理机、总管理机除外)、主机(副机除外)、围墙机，每台必须配置一个。它是联网的必要设备，有了它，除了可以节省线材外，还可以减少布线的很多麻烦。

2) Networks: sub-managers (excluding building managers and general managers), mainframes (excluding deputy managers) and fencing machines, each of which must be equipped with one. It is the necessary equipment for networking. With it, besides saving wires, it can also reduce many troubles in wiring.

3)解码器：是联接主机与分机的桥梁。它的作用有三个：a故障隔离;b扩大分机容量;c延长主机至分机距离。有些对讲系统不用解码器，但缺陷是明显的，因为分机与主机连接采用总线方式，所以只要有某一户分机总线出现故障，导致整栋系统瘫痪，而且分机的数量与距离均受到限制。

3) Decoder: It is a bridge connecting mainframe and extension. It has three functions: a fault isolation; B expands the capacity of extension; C extends the distance between host and extension. Some intercom systems do not need decoders, but the drawbacks are obvious, because the connection between extension and host adopts bus mode, so as long as one branch bus fails, the whole system will be paralysed, and the number and distance of extension are limited.

工作原理

Working principle

楼宇对讲系统一般的工作原理：各个终端设备的工作，都是在网络交换机的指挥下，协调工作。终端设备的联络是通过通信信令来完成，从物理层上讲，是通过网线(总线)连接在一起。目前，比较流行的现场总线有RS485总线、CAN总线、Lonwork等，性价比较优的是RS485总线，在不接中继的情况下，它能以9600BPS通信速率传送1200m，性能稳定可靠，因而大多数智能对讲系统采用该总线联网。

The general working principle of building intercom system: the work of each terminal equipment is coordinated under the command of network switch. The connection of terminal equipment is accomplished by communication signaling, and from the physical level, it is connected by network line (bus). At present, the popular field buses are RS485 bus, CAN bus, Lonwork and so on. The RS485 bus has better performance and price. Without relay, it can transmit 1200m at 9600BPS communication rate, and has stable and reliable performance. Therefore, most intelligent intercom systems use this bus network.

RS485总线基本特性

Basic Characteristics of RS485 Bus

根据RS485工业总线标准，RS485工业总线为特性阻抗120Ω的半双工通讯总线，其最大负载能力为32个有效负载(包括主控设备与被控设置)。

According to RS485 industrial bus standard, RS485 industrial bus is a half-duplex communication bus with characteristic impedance 120_. Its maximum load capacity is 32 payloads (including main control equipment and controlled settings).

RS485总线传输距离

RS485 Bus Transmission Distance

当使用0.56mm(24AWG)双绞线作为通讯电缆时，根据波特率的不同，最大传输距离理论值如下表：

When using 0.56mm (24AWG) twisted pair as communication cable, according to the different baud rate, the theoretical value of maximum transmission distance is as follows:

波特率最大距离

Maximum distance of baud rate

2400BPS 1800m

2400BPS 1800m

4800BPS 1200m

4800 BPS 1200m

9600BPS 800m

9600BPS 800m

当使用较细的通讯电缆，或者在电磁干扰较强的环境使用本产品，或者总线上连接有较多的设备时，最大传输距离相应缩短;反之，最大距离加长。

When using thin communication cables, or using this product in the environment of strong electromagnetic interference, or connecting more devices on the bus, the maximum transmission distance will be shortened correspondingly; conversely, the maximum transmission distance will be lengthened.

主干网上的设备，如围墙机、管理机、主机等均分配一个ID号，即通信联络地址。主干网对讲线，一般都是用一芯线(地线除外)，是一种半双工方式。视频用一根同轴电缆。如果要求有多对访客住户同时进行对讲(所谓多通道)，则必须增加音频线和视频线。

Equipment on the backbone network, such as fencing machines, managers, hosts and so on, are assigned an ID number, that is, a communication contact address. Backbone interphone is usually a half-duplex mode with one core (except ground). The video uses a coaxial cable. If more than one pair of visitor households are required to talk at the same time (so-called multi-channel), audio and video lines must be added.

主机(副机)与分机一般不能直接连接，中间必须增加解码器，这有利于系统的稳定和增强抗干扰能力。

In general, the host (auxiliary) and the extension can not be connected directly. Decoder must be added in the middle, which is conducive to the stability of the system and the enhancement of anti-jamming ability.

主机(副机)与解码器均通过一个叫做网络联接器的设备在弱电井内连接，解码器与解码器之间总线方式或是星型方式连接。每个解码器也有一个ID号，是主机与之通信的联络地址。(二进制编码)

Host (auxiliary) and decoder are connected in weak electric well through a device called network connector. The decoder and decoder are connected by bus or star mode. Each decoder also has an ID number, which is the contact address with which the host communicates. (Binary Coding)

主机与解码器之间的连线，叫楼内总干线，所用电缆芯数因厂家不同而有所区别，如慧锐通R2系统用四芯线，其功能为：二芯为音频线，一芯为可视对讲线，当围墙机、主机(副机)呼叫住户时，用此线对讲，另一芯为非可视对讲线，当总管理机、分管理机或栋管理机与住户对讲时，用此线对讲。由于有两芯对讲线，实现了楼内对讲双通道，减少了占线几率。剩下的两芯，一为GND，另一为数据通信线，如开锁、报警等均用此线传递信息。

The connection between host and decoder is called the main line in the building. The number of cable cores used varies from manufacturer to manufacturer. For example, Huiruitong R2 system uses four cores. Its function is: two cores are audio cores and one core is visual intercom cores. When fencing machine and host (auxiliary machine) call households, the other core is non-visual intercom cores. When the main manager, branch manager or building manager calls for households, the other core is non-visual intercom cores. When talking to the household, use this line. Because of the two-core intercom line, the double-channel intercom in the building is realized, which reduces the probability of busy line. The remaining two cores, one is GND, the other is data communication line, such as unlock, alarm and so on, all use this line to transmit information.

楼宇对讲产品在小区智能化系统中一向背负着最多的骂名，最难听的甚至有“一年正常，三年半通，五年全不通的说法”，为什么?下面我们一起看看楼宇对讲存在哪些环境隐患。

Building intercom products always bear the most abusive names in the intelligent system of the community, and the most ugly even have "one year is normal, three and a half years, five years are not clear at all." Why? Let's see what environmental risks there are in building intercom.

1、杂物堆积

1. Accumulation of debris

杂物堆积，貌似和楼宇对讲没什么关系，但影响电井内部设备的散热，在电井内相关电子设备故障可能产生电火花或火苗时，将成为引发火警的燃料。因此锁好弱电井的门，不让住户将杂物放到弱电井中是物业管理应该重视的。

The accumulation of debris does not seem to have much to do with building intercommunication, but it affects the heat dissipation of the equipment inside the electric well. When the malfunction of the related electronic equipment in the electric well may cause sparks or sparks, it will become the fuel for fire alarm. Therefore, the property management should pay attention to locking the door of the weak electric well and preventing households from putting sundries in the weak electric well.

2、灰尘影响

2. Dust effect

一般来说，电井属于相对密闭环境，但因为长时间无人进出可能积累较多灰尘，又或者电井中其它施工项目施工过程中，可能产生大量的粉尘堆积，

Generally speaking, electric wells belong to a relatively closed environment, but because no one enters or exits for a long time, it may accumulate more dust, or during the construction of other construction projects in electric wells, it may produce a large amount of dust accumulation.