Many households have a building intercom system for the convenience of opening the security door. Since most of the building intercom systems do not provide circuit diagrams, which causes difficulties in the maintenance of the building system, the author repairs several sets of building intercom systems, clarifies the working principle of the system, draws the circuit schematics and wiring diagrams against the actual board. And a brief analysis of its working principle for reference during maintenance.
Common building intercom systems have three types: direct-press intercom system, digital intercom system, and visual intercom system. The structure of the building intercom system is shown in Figure 1. It consists of five parts: the main unit, the extension (one extension per household, only two extensions in the figure), the electric lock, the power supply box and the connection system.
The working process of the whole intercom system is: the power supply box provides power to the host, and the internal step-down charging circuit and the battery are provided. After the mains is stepped down, rectified, and filtered, the battery is charged, and the battery is supplied with power when the utility power is cut off. The host computer is the core of the whole system, and is internally provided with a power control circuit, a call circuit, an intercom circuit, a video circuit, an unlock circuit, etc., and is connected through a call line, a transmission line, a telephone line, a video line, an unlock line, a ground line, and the like. The line is connected to the user's extension. If the visitor wants to enter the building, first press the user number button on the security door host, the ringing of the household extension will ring, the resident will check the incoming person through the intercom system and video system after picking up the phone, and then press the unlock button to make the host The unlocking circuit acts to open the electronically controlled lock of the security door.
1. Direct-press intercom system
Each household on the host sets a call button, and each button is connected to the corresponding resident through the call line, as shown in Figure 1. Directly press the household call button to directly call the resident, intuitive and easy to use, but no security features. In addition to the four lines of the transmission line, the telephone line, the unlock line and the ground line, each household needs a call connection line. If there are 20 households in the building, you need 20 call lines. The cost of the host system of this type of call system is relatively low, but the cost of the connection system is high, and the number of circuit connections is large, and the connection is complicated.
2. Digital intercom system
Set 0 to 9 ten-digit keys on the host, built-in code recognition system, each household sets a set of digital codes, enter the password of the household, in order to call the household, if you do not know the household code, can not call, have a certain degree of confidentiality Function to prevent users from being disturbed for no reason. All users of this type of intercom system can connect with the host through a call sharing line. After inputting the number, the coding system recognizes and calls the corresponding user. The cost of the host system of this kind of building intercom system is relatively high, but the connection system has few connection lines and low cost, and only five common lines of call line, send line, voice line, unlock line and ground line are needed.
3. Video intercom system
The video intercom system is divided into a direct-type video intercom system and a digital video intercom system. In addition to setting the camera on the main unit and setting the imaging equipment on the extension, the system is connected on the basis of the above-mentioned type 1 and 2 connection lines. There is also a need to add video signal cables or video amplifiers, and each user needs to add a small power supply for video display.
The Lilin JB-220V building intercom system introduced in this paper, the host circuit will be incorporated into the unlocking circuit, and the transmission system will share a line and reduce the wiring.
ZGAR FILTER TIP
ZGAR electronic cigarette uses high-tech R&D, food grade disposable pod device and high-quality raw material. All package designs are Original IP. Our designer team is from Hong Kong. We have very high requirements for product quality, flavors taste and packaging design. The E-liquid is imported, materials are food grade, and assembly plant is medical-grade dust-free workshops.
Our products include disposable e-cigarettes, rechargeable e-cigarettes, rechargreable disposable vape pen, and various of flavors of cigarette cartridges. From 600puffs to 5000puffs, ZGAR bar Disposable offer high-tech R&D, E-cigarette improves battery capacity, We offer various of flavors and support customization. And printing designs can be customized. We have our own professional team and competitive quotations for any OEM or ODM works.
We supply OEM rechargeable disposable vape pen,OEM disposable electronic cigarette,ODM disposable vape pen,ODM disposable electronic cigarette,OEM/ODM vape pen e-cigarette,OEM/ODM atomizer device.
Vape Filter Tip,Disposable Pod Vape,Disposable Vape Pen,Disposable E-Cigarette,Electronic Cigarette,OEM vape pen,OEM electronic cigarette.
ZGAR INTERNATIONAL TRADING CO., LTD. , https://www.szdisposable-vape.com