Management and maintenance of communications power supply

1 Composition of communication power supply system

Power supply is an important part of communication system. A complete communication power supply system consists of 5 parts: AC distribution unit, rectifier module, DC distribution unit, battery pack, and monitoring system. Such a combined communication power supply system has a wide range of application significance. It is not only applicable to power system communication, but also to all private network communications and public network communications.

2 Basic requirements and characteristics of communication power supply

The basic requirements for communication power supply system are reliability and stability. Generally, the impact of communication equipment failure is small and local, but if the communication power supply system fails, the communication system will be completely interrupted. Therefore, the power supply system must have backup equipment, the power supply equipment must have spare parts, the mains must have dual or multiple inputs, and AC and DC must be used as backup for each other. China's requirements for communication power supply are: lightning protection measures must be perfect, the AC input voltage fluctuation range allowed by the equipment is large, and multiple backup systems must be used to prevent the power supply system from completely interrupting the power supply. Due to the wide variety of power grid distribution and the conditions for using mains power, the mains voltage fluctuation range in many places is very large. In particular, some substations, microwave stations, optical communication stations, modules, etc., sometimes the AC voltage fluctuation range is more than ±30%. In order to improve the availability of the mains electricity, the power supply equipment is required to have a wider operating voltage range, otherwise it is necessary to add a voltage stabilizing device.

3 Management of communication power supply

(1) Strengthen the attention to power supply equipment

Power supply equipment is quite different from other equipment in the communication network (such as switching, transmission, etc.). In essence, power supply equipment is electromechanical equipment rather than communication equipment. Because of this, it has not received sufficient attention in the communication industry, and it cannot be guaranteed in terms of organization, personnel, funds or management. However, it must be seen that as the energy guarantee of the entire communication and telecommunications network, the role of communication power supply is holistic and global. Although it is not the mainstream equipment in the communication network, it is the most important and critical equipment in the communication network.

(2) Strengthen the specialization of power supply management

Communication power supply requires that all levels of management, construction and maintenance of the communication network should have independent power supply professional management organizations and personnel. Because communication power supply is a profession, and a large profession that includes multiple systems and disciplines, it should be managed accordingly. It is not enough and unscientific for other professionals to manage the power supply profession.

(3) Pay attention to the initial design and installation of the communication power supply system.

When designing the power supply system, full consideration should be given to the capacity, geographical location, spatial layout, future development, equipment quality, engineering survey and design, operation mode selection, construction management, operation and maintenance management, etc. Among them, the equipment selection, scheme design, engineering management and other links should be paid special attention to and managed.

(4) Specific measures for the purchase and maintenance of power supply equipment

1) In the process of purchasing communication power supply, in addition to considering the cost performance, high reliability, multiple automatic protection functions, wide voltage, good current balancing performance, online operation mode, and whether the production is strictly organized in accordance with the ISO-9000 quality assurance system should be considered. In addition, the system failure rate, lightning protection and surge protection measures, AC and DC power distribution integration, etc. should be the focus of analysis and consideration of configuration. Equipment with high reliability should be selected and backup equipment should be reasonably configured.

2) The power supply mode should vigorously promote decentralized power supply, have spare parts and backup, use communication equipment with the same DC voltage, and use more than two independent power supply systems. 3) In order to minimize the average fault repair time of equipment, it is necessary to frequently analyze operating parameters, predict the occurrence of faults, and eliminate them in a timely manner. 4) The equipment should be modular and hot-swappable to facilitate replacement and maintenance. Another thing is to establish emergency measures for power failures to ensure reliable power supply. Finally, we should improve the level of technical maintenance and vigorously promote the centralized maintenance system.

Implementing centralized monitoring and management is an inevitable trend of technological development, a need for modern communication networks, and one of the measures for enterprises to reduce staff and increase efficiency. With the increasing integration and miniaturization of communication equipment, various power supply equipment must also be intelligent, standardized, and comply with open communication protocols. Centralized monitoring must be implemented step by step. During the implementation process, the equipment of the three remote (remote signaling, telemetry, and remote control) points must be reasonable, and the more the better, otherwise the effect will be counterproductive.

4 Strengthen battery maintenance

The communication power supply covers a wide range. It should at least include several major systems such as AC high and low voltage, self-provided diesel generators, USP, rectifiers, battery packs, lightning protection grounding, and power environment monitoring. Among these systems, DC systems and UPS directly supply communication loads, so they are the most important. In these systems, batteries are the most critical in the entire power supply system as a guarantee of uninterrupted power supply. Batteries not only ensure uninterrupted power supply when there is a problem with the AC system or rectifier, but also provide guarantees when the mains and self-provided diesel generators are normally converted. Therefore, batteries are the key to the maintenance of the entire communication power supply system.

In the daily maintenance of the communication power supply system, the maintenance test and diagnosis of the battery are very tedious and must be very meticulous. The communication system now uses maintenance-free sealed batteries, which are relatively simple to maintain.

The battery maintenance matters are as follows:

the battery has been initially charged when it leaves the factory. Do not short-circuit the positive and negative poles. During transportation or storage, part of the capacity will be lost due to self-discharge, so it should be fully charged and discharged before use to replenish the electrical parameters; when carrying the battery, carry the bottom of the battery and never apply force on the terminal; never open the exhaust valve; valve-controlled lead-acid maintenance-free batteries do not need to check the liquid level or add water before use. Do not place the battery near spark-generating objects or in sealed places; maintenance-free lead-acid batteries can be placed horizontally or vertically, but should be used upright under frequent vibration conditions; adjacent batteries can be connected more tightly, but when multiple columns are used side by side, the distance between each column should be kept at about 10mm for better heat dissipation; after connection, each conductor should be covered with an insulating cover and tightened; if not used immediately after charging, it should be placed in a high temperature environment as far as possible, and the temperature should be kept at a low temperature. The higher the temperature, the greater the self-discharge; after long-term storage, sometimes the capacity cannot be fully restored without several cycles of charge and discharge; during discharge, the ambient temperature should be controlled within the range of -15℃--+45℃; the charging and discharging device must choose a constant voltage current limiting or an automatic constant voltage device with a decreasing characteristic, and the charging voltage accuracy is preferably within ±2%; whether the battery is used or not, it should be charged and discharged regularly (3 months or 6 months); when cleaning the battery, a wet cloth should be used, and a dry cloth or chemical fiber cloth may crack the battery shell, causing leakage or corrosion and fire; when inspecting and maintaining, protective items such as rubber gloves and rubber shoes should be worn; if the battery pack capacity drops below 60% of the rated capacity, it can be regarded as the end of life; when used on converters such as UPS, capacitors should be installed to prevent the return current from the converter from flowing into the battery.

5 Lightning protection of communication power supply system

The management of communication power supply also includes management measures for externally introduced current and voltage. Touching power lines and lightning strikes are the main ways to introduce strong current and voltage. 5.1 Hazards caused by lightning strikes

Lightning strikes generate strong currents and high voltages that can cause serious damage to both human bodies and equipment. Direct or indirect lightning strikes can cause great harm to communication equipment. Lightning protection is a systematic project. The use of certain effective technologies and devices can only reduce the probability of lightning strike hazards and reduce damage. All cables and wires entering and leaving the office must be shielded and lightning-proofed, and a complete grounding system must be used. Grounding must be strictly carried out in accordance with regulatory requirements to reduce lightning damage.

5.2 Lightning protection grounding

In order to prevent the overvoltage and overcurrent generated by lightning from damaging the power supply equipment, a lightning protection grounding device is generally provided in the communication power supply system, and its grounding resistance is ≤5Ω. In places with low soil resistivity, the grounding resistance should be ≤1Ω. In the communication power supply system, the lightning protection grounding wire must be separated from the working grounding wire and the protective grounding wire, while in the power communication power supply system, the lightning protection grounding, working grounding, and protective grounding are required to share the ground wire.

Various lightning protection and grounding technologies have been developed. These are important technologies to ensure the reliability of communication networks and are also important basic technologies in the field of communications. The commonly used joint grounding system and incoming and outgoing line lightning protection system and various security devices are currently effective methods. To do a good job in lightning protection of communication equipment, it is also necessary to use lightning rods, lightning strips, lightning lines, lightning nets and other equipment that are relatively mature in theory and practice to induce lightning current to enter the earth through the grounding wire. Facts have proved that the joint grounding system and the incoming and outgoing line lightning protection system can greatly reduce the probability of lightning damage when they are well handled.

From the purpose of grounding, especially for outdoor equipment grounding, leakage prevention and lightning protection are particularly important. The grounding resistance requirements for them can be implemented in accordance with the provisions of the technical specifications. In order to ensure that the grounding resistance value meets the requirements of the specifications, it is very necessary to inspect and test the grounding and grounding resistance after construction. Regular or irregular testing of grounding resistance and inspection of the grounding device system are necessary systems that should be adhered to.

6 Conclusion

In summary, in the composition of the communication network, power supply is its "blood" and a necessary condition to ensure smooth communication. Only by paying enough attention subjectively and creating a good objective operating environment, achieving professional and institutionalized management, advanced equipment and technology, and modern operation and maintenance, can the safe production and operation of the communication power supply system and the communication system be guaranteed, and reliable and smooth communication be ensured.