Building intercom system failure site exclude Case Analysis
Release date:2016-01-13
Residential building intercom system has entered every household, there are networking systems, video systems, intercom systems, etc., system wide range of engineering problems encountered during the installation process is also varied. Based on years of field experience, summed up the most common types of problems, each of which issues are to do a detailed analysis, hoping to help to contractors.
First, Sanmenxia site
Symptom: Direct press color visual system, six floors 12, sixth floor, no color.
Process of elimination: first telephone guidance Sanmenxia customers check the line, but also to the other manager to check the construction workers, construction workers have been reflected in that there is no problem. Our engineers again telephone guidance: The six-story extension no color change to the fifth floor, the result will have color, indicating the extension hosts are no problems, the problem is on the line, so once again stressed that the focus of inspection 5th floor line. But the construction workers do not want to take responsibility, let the other managers give us a call, strongly urge the factory to send engineers to the site to check. After engineers to find: the extension office on the fifth floor then, there are two 18-volt power lines, including construction of a multi-core wire is stripped off by more than a dozen copper wire, wire cross-sectional area of 0.5 would have had 28 copper wire, now It only has a dozen roots, resulting in a serious decline in voltage, never affect no color.
Workaround: Reconnect stripped off portion 18V power cord.
Lessons learned: a sense of responsibility and attitude whether strict construction taker, is very important. No sense of responsibility for individual construction staff, a small mistake can lead to its serious consequences.
Second, Xinyang Yihe Garden District site
Symptom: coding color visual system, extension image distortion and color reproduction over.
Workaround: In the video mainline ground plus 75-ohm termination resistor.
Principle Analysis: Each extension building systems in parallel video signals are superimposed on one main video so that the video signal is stronger, so the extension image appeared distorted image, a strong color phenomenon. In the video the main line on the ground plus 75 ohm, weakened portions of the video signal, the image back to normal.
Third, Xinyang City Longcheng Jiayuan residential site
Symptom: black and white video coding system, which has serious moire appears when a user extension monitor door host image.
Solution: Replace an extension video cable.
Principle Analysis: user-supplied video cable production process is poor, non-standard video cable, video cable copper core wrapped in an intermediate position not belong eccentricity, leading to problems with the video extension.
Lessons learned: user-supplied wire, can not the pursuit of low prices, while low prices to a certain extent, necessary to strictly check the quality of the wire, copper clad aluminum, copper clad steel, non-standard, doping practices. Recommended regular factory wire, Hong Kong TPV in Beijing have a wire and cable, the quality is reliable.
Fourth, Luohe Golden crape myrtle garden scene
Symptom: Direct visualization systems by door noise during standby host.
Workaround: Use wire to 20V power supply "ground" and the earth is turned on. Both on the host is connected to the door shell or negative 20 volts. If the door is not properly grounded, you can put 20 volts negative wire pulled directly on the earth, and driven into the ground about one meter reinforced around the spill brine.
Principle Analysis: The cell power ground situation is not good, causing interference signal is not directly into the earth, but after the formation of noise amplified by master amplifier.
V. Long Boyuan Xinxiang County Garden site
Symptom: coded visual card systems, electronically controlled lock can not be opened
Workaround: Reconnect the 12V power line
Principle analysis: workers in the wiring of the 12V power line caused a lot of copper wire stripping off. Because unlock current large, if the 12V power line wire stripping off the equivalent of 12V power line is very thin, that there is no shortage of current and voltage lock.
Sixth, the liberated areas of Jiaozuo City Bureau of Education site
Symptom: black and white video coding system, 16 a layer two households, image ghosting and lower floors is more serious
Solution: (1) building type isolator.
(2) In the seven floors of the video cable is disconnected, and then eight more than one extension from the host that pull a video cable, host video output to add a video isolation, so that the video signal is divided in two, all the way video line with the 1-7 layer, another video cable with 8-16 layers.
(3) or do not pull the video cable, then seven more video signal is necessary from seven of the video isolator output up band.
Principle Analysis: Because video signals require transmission point, the higher the floor, the video signal is down the more serious reflection on the emergence of ghosting, so executives must use these methods to troubleshoot video problems.