Popularize the daily use and maintenance of optical multiplexer

Time : Jul. 08, 2022    View : 57

In today’s Internet era, optical multiplexer have provided great help for people’s life and work. In order to effectively prolong the service life of the optical multiplexer, we need to pay more attention in our daily work. Know that good usage is directly linked to the length of service life. Today, the editor will share with you the daily use and maintenance of the optical multiplexer. Come and take a look!

  1. Optical multiplexerpower supply and installation environment

    Generally, since the installation position of the transmitter follows the front-end video capture device, the installation position is relatively scattered, and an independent chassis is required to supply power to it. In terms of security monitoring power supply, there are usually two ways: central centralized power supply and local power supply. Because the distance between the front and rear ends is relatively long in the field where the optical multiplexer is used, the centralized power supply method is rarely used. The receivers are generally located in the computer room of the monitoring center. They are not as scattered as the transmitters. In terms of power supply mode, if the power supply is powered by the chassis power supply like the front-end transmitters, it will occupy a lot of space in the computer room, which is disorganized and cannot be managed uniformly. Therefore, the power supply of the central receiver can be powered by a plug-in chassis. Do not fill all the slots. You can open one every few slots, which is beneficial to the heat dissipation of the optical multiplexer. It should be noted that the laser components and photoelectric conversion modules of the optical multiplexer should not be impacted by instantaneous pulse current, so it is not suitable to switch the machine frequently.

    The front-end transmitter is mostly installed in the front-end distribution box. Pay attention to the dustproof and waterproof of the distribution box. When the distribution box is plugged and full, it is necessary to consider the distribution box with a fan in order to facilitate the heat dissipation of the optical multiplexer. The equipment room of the monitoring center should be kept clean and tidy, and it should be cleaned frequently to avoid dust accumulation. It is best to install the equipment into the equipment room after the equipment room is renovated. In the equipment room, there are generally many equipment installed in the cabinet, and the equipment generates a lot of heat. When the ventilation and heat dissipation conditions are poor, it is best to install an air-conditioning system to ensure the normal operation of the optical multiplexer. When installing the optical multiplexer, it is necessary to take on-site protective measures to prevent moisture, water, and dust. At the same time, pay attention to the actual operation on site. It must be equipped with suitable optical fibers for use. , When it comes to optical cable fusion, it is also necessary to pay attention to measuring the optical attenuation or loss of the optical cable within the effective value range.

  1. Lightning protection of optical multiplexer

    Optical multiplexer, especially transmitters as front-end equipment, are usually installed in outdoor equipment boxes. The on-site environment is quite harsh, and lightning protection is extremely important. The pros and cons of lightning protection measures directly determine the probability of optical multiplexer failures. The destruction methods of lightning are mainly divided into three forms: direct lightning strike, induction lightning and ground potential counterattack. The most serious impact on the optical multiplexer is the ground potential counterattack.

    The so-called ground potential counterattack is that when the lightning rod and other lightning receptors leak the strong lightning current that directly strikes the lightning into the earth through the downconductor and the grounding body, there will be a very high moment on the downconducting wire, the grounding body and the metal objects connected to it. Voltage, this high voltage will produce a huge potential difference between metal objects, cables and other electronic devices that are close to them but not in direct contact. The electric shock caused by this potential difference is the ground potential counterattack. The ground potential counterattack damages the optical multiplexer in the following form: when the lightning current leaks into the ground, the ground potential of the grounding grid will be raised to tens of thousands or hundreds of thousands of volts within a few microseconds. Highly destructive lightning current will flow from the grounding part of various devices to these devices, or to other nearby devices by puncturing the ground insulation, eventually causing damage or damage to the devices. The damaged parts mainly include: the PCB board of the chassis power supply Upper electronic components, chips at video interface and related electronic components, chips at audio and data ports.

    Although there are various forms of damage caused by lightning, it is still possible to reduce the probability of optical multiplexer failure by taking scientific protective measures. First of all, ensuring that the grounding device works well is the premise of lightning protection measures, because all induced currents will eventually leak into the ground. Generally speaking, the smaller the grounding resistance, the better the leakage effect. Usually, it is better to control the grounding resistance within 4 ohms. You can use a grounding clamp meter to measure the grounding resistance. For some places with high soil resistivity, you can consider adding a resistance reducing agent to the soil to reduce the grounding resistance. Secondly, the front-end equipment should be equipped with a surge protector. When the voltage is normal, the surge protector is in a high resistance state, with only a small leakage current, and the power loss is very small. When there is overvoltage in the line, the surge protector In the low resistance state, the overvoltage flows into the ground through the surge protector in the form of discharge current, and the overvoltage is suppressed. After the surge voltage passes, when the line voltage returns to normal, the surge protector is in a high resistance insulation state, so the surge The protector must be matched with a good grounding device. The video signal output port of the front-end camera and the video input port of the transmitter are connected to a surge protector. If the transmitter is connected to some other data lines, it is necessary to install a data surge protector at the beginning and end of the control signal line. In addition, lightning protection devices such as power lightning arresters are also added to the power input terminals of cameras and optical multiplexer. When installing the lightning protection device, make sure that the lightning protection device is close to the access port. If the lightning protection device is too far away from the video port and data port, the lightning protection effect will not be exerted.

    After adding lightning protection equipment, the rest is the design of the grounding grid. The grounding pile must be in place to ensure the optical multiplexer is well grounded. A good low-impedance grounding grid design can ensure that the lightning protection equipment in the system has a good effect and can effectively balance the voltage of each part in the entire transmission system, preventing the ground potential difference from affecting the line. The interference of the equipment can also be effectively avoided from the damage to the equipment caused by the ground potential counterattack.

  1. Debugging of optical multiplexer

    After doing the above points, it is necessary to start the normal debugging, mainly debugging the optical fiber and data channel. Since there are many optional types of optical multiplexer data, according to the actual needs of the site, the data types of the optical multiplexer used in the field are also different. When debugging, you must refer to the corresponding manual and follow the data dialing and interface definition in the manual. data wiring.

    Due to the complex environment of on-site installation of optical multiplexer, some users usually first suspect that the product is faulty when debugging fails. In fact, the optical multiplexer product technology is very mature, and the products have been repeatedly tested and copied before leaving the factory, so the product itself is less likely to have problems. Therefore, when there is a problem on site, the first thing to consider is the installation problem, which can be checked from the following aspects:

    3.1. The optical fiber itself has not been tested, the optical path is blocked or unstable, or the optical attenuation is too large;

    3.2. Front-end equipment failure, such as no video or no power on the camera;

    3.3. The back-end equipment is faulty, such as the monitor has no video, the keyboard control protocol is wrong, and it cannot be controlled by itself;

    3.4 The connection line is faulty, such as the video head is not soldered well, the control line is wrongly connected, or the connecting line is crossed and connected wrongly, reversely, etc.

    The above phenomena, especially line faults, have the greatest probability of occurrence, and need to be carefully checked when encountering problems. When troubleshooting, you can use the exclusion method, one device at a time, and finally accurately determine the key to the problem. When judging whether there is a problem with the optical multiplexer, it is recommended that the user put the transmitter and the receiver together for a short-distance test. If it still does not work, the optical multiplexer itself is faulty, and it is necessary to contact the manufacturer for replacement. In order to reduce problems, the user should test the optical multiplexer as close as possible before installation, so that the installation and debugging can be quickly passed and the construction period is saved.

  1. Daily maintenance of optical multiplexer

    Usually, the working environment of the optical fiber terminal is quite harsh, so pay attention to keep the fiber head clean when using it. The optical multiplexer is very sensitive to dust. During the transportation of the optical multiplexer or after the customer has used it for a period of time, there may be dust or debris at the optical fiber port, which may cause blockage, thereby affecting the normal transmission of video and data. Use water alcohol and lint-free paper to clean the fiber head to prevent dust from adhering to it.

    The optical fiber jumper inside the optical fiber is connected to the external optical fiber through an adapter. Usually the adapter is a ceramic tube core. When plugging and unplugging the optical fiber head, special attention should be paid. Do not use improper force to prevent the ceramic sleeve from being cracked or crushed. The optical multiplexer cannot transmit the signal normally.

    The above content is mainly introduced to you around the daily use and maintenance of the optical fiber transceiver. I hope you can master the correct use method through the introduction of the above related content. After all, no one has extra money, and it is the common goal of everyone to strive for a lifetime of use.