Communication Room Power Supply Maintenance Guide

In the communications industry, people usually compare the power supply to the "heart" of the communications system. The stability of the quality of the communications power supply is crucial to the stability and smoothness of the entire communications network system, and directly affects the safety and quality of communications. Therefore, it is necessary to do a good job in the maintenance of each device of the communications power supply to ensure the continuous and stable operation of the communications power supply. Here are some of my personal opinions on the maintenance requirements of each device of the communications power supply and the test instruments that need to be used in daily maintenance work: 1. Power supply quality standards To provide uninterrupted power supply to communications equipment, the power supply quality must first be guaranteed to meet the standards. In China Telecom's "Telecommunications Power Supply Maintenance Regulations" (hereinafter referred to as the "Regulations"), the DC power supply voltage, DC power supply circuit connector voltage drop (connectors other than the DC distribution panel), AC mains power supply, and AC oil generator power supply are specified. Detailed requirements are made for various parameters such as voltage, noise voltage, frequency, power factor, etc. in the power supply standards of the Regulations. At the same time, the relevant regulations in the regulations also make detailed provisions for parameters such as the imbalance of the three-phase power supply voltage and the sinusoidal distortion rate of the voltage waveform. From the above standard requirements, it can be seen that the following test instruments are needed in the test of daily power supply quality: 1. Multimeter. As one of the necessary test tools in daily maintenance work, the multimeter is mainly used to test related parameters such as voltage, current, frequency, etc., and its resolution is required to reach at least 41/2 bits. At present, maintenance personnel usually use the high-precision digital multimeters of the F80 and F180 series of FLUKE companies in the United States. The resolution of this type of multimeter can reach 44/5 bits, which can fully meet the requirements of the "Regulations" for test accuracy. At the same time, this type of multimeter has good anti-fall, anti-burn, anti-magnetic, anti-sputtering, intelligent alarm and other characteristics, which are very suitable for maintenance site use. 2. AC/DC clamp meter AC/DC clamp meter is also one of the necessary test tools in daily maintenance work. It is mainly used to test related parameters such as voltage, current, frequency, etc. It is required to have high test resolution, test accuracy and more test functions. At present, maintenance personnel usually use F337 AC/DC dual-purpose clamp meter (true effective value) produced by FLUKE Company of the United States, and SGT-11A and SGT-12B single and double jaw clamp meters produced by Silicon Valley Communication. This type of instrument has the characteristics of large jaw diameter, high test resolution and accuracy, and accurate small current and inrush current measurement. At the same time, the humanized design of this type of clamp meter is very suitable for use in occasions with small space. 3. Noise meter Noise meter is mainly used to test the pulsating component in the output voltage of rectifier equipment and DC converter, that is, noise voltage. At present, the noise meters on the market are mainly divided into analog and digital types. The analog noise meter is mainly JH5151 of the state-owned Jianhua Instrument Factory. Although it is large in size and heavy in weight, it has many test indicators and high accuracy. The digital noise meters mainly include FZY-120 and FZY-120A, which are light and portable, simple to test, and intuitive to display. At present, maintenance personnel can choose to use them according to their preferences. 4. Power quality analyzer. Power quality analyzers are mainly used for single-phase and three-phase power measurement, voltage event capture, harmonic measurement, and three-phase unbalance measurement. At present, maintenance personnel usually use the F43B power quality analyzer of FLUKE in the United States or the domestic PQ-2S and PQ-3 power quality analyzers. This type of analyzer has the characteristics of simple operation, complete functions, and accurate testing, which is very suitable for grassroots maintenance personnel. 5. Oscilloscope. The oscilloscope is mainly used to measure the sinusoidal distortion rate of the voltage waveform. At present, maintenance personnel usually use the F123 or F190 series portable dual-channel multi-function oscilloscopes of FLUKE in the United States. This type of oscilloscope has the characteristics of high test accuracy, instant measurement, simple operation, and humanized design. It is specially suitable for fault diagnosis and troubleshooting of communication power supply systems and on-site maintenance of communication equipment. 2. Battery maintenance The battery is the last guarantee for the normal operation of the communication power supply system after the mains power is interrupted. The remaining capacity of the battery directly determines the time the battery pack can provide power. Therefore, the regulations have detailed provisions for battery charging and discharging as well as daily testing and maintenance. At present, the battery capacity test products on the market are mainly divided into conductivity test and internal resistance test. The basic situation of these two types of products is that the conductivity tester can display the voltage, conductivity value and relative percentage capacity of each single cell through online (without disconnecting the battery from the system) rapid testing. At the same time, the conductivity tester is light and portable, which is very suitable for maintenance personnel to use in daily battery maintenance work; while the internal resistance tester needs to disconnect the battery from the system and discharge it for a long time (more than 10 hours) to measure the capacity of the battery, which not only increases the risk of maintaining normal operation of the system, but also wastes a lot of manpower and thermal energy resources. At the same time, the instrument is too heavy (at least more than 10 kilograms), which causes a lot of inconvenience to maintenance personnel in daily battery maintenance work.
In addition, from the perspective of practical application, the conductivity tester products - CTA-4000 and CTU-6000 battery conductivity meters of Midtronics Company in the United States have been widely used in well-known foreign operators such as British Telecom, France Telecom, and Time Warner Telecom in the United States; and domestic users include power supply maintenance personnel of provincial and municipal companies of multiple operators such as Zhejiang Mobile, Fujian Telecom, Inner Mongolia Telecom, and Inner Mongolia Mobile. At present, more and more domestic power maintenance personnel have accepted the concept of conductivity testing and started to use CTA-4000 and CTU-6000 conductivity meters in daily battery maintenance work, which not only innovates battery maintenance work, but also greatly improves work efficiency and reduces labor. 3. Maintenance of power distribution equipment As an important part of the AC power supply system, the power distribution equipment is directly related to the DC power supply. Therefore, the regulations have made corresponding provisions for the maintenance of high-voltage distribution equipment, low-voltage distribution equipment, and AC voltage stabilizers, and some important items, such as: the phase sequence of AC power supply and power equipment, cable energization part detection, power cable insulation detection, etc., have been detailed. It can be seen that in the daily maintenance of power distribution equipment, in addition to the AC and DC clamp meters, the following instruments should also be used:
1. High and low voltage test pens. High and low voltage test pens are mainly used to check the energized parts of live busbars. At present, maintenance personnel usually use the F1 LAC (low voltage) / AC (high voltage) induction test pens from the American FLUKE company. This type of test pen uses induction testing and does not require physical contact, thus greatly ensuring the personal safety of maintenance personnel.
2. Phase sequence meter. The phase sequence meter is mainly used to test the phase sequence of AC power. At present, maintenance personnel usually use the 3126 phase sequence meter from Japan's HIOKI company. This type of phase sequence meter is light and portable, and the test is simple, which is very suitable for use on the test site.
3. Digital megohmmeter. The digital megohmmeter is mainly used to test the insulation of power cables. At present, maintenance personnel usually use the 3453 digital megohmmeter from Japan's HIOKI company. This type of megohmmeter has the characteristics of intelligence, large test range, and dual digital and analog display. It is one of the necessary instruments in maintenance work. 4. Lightning protection and grounding Since all equipment in the communication power supply system needs to take lightning protection measures, the grounding system of the entire system is required to be relatively high. The regulations have made specific requirements for the grounding resistance values ​​of various communication stations. At present, the most commonly used grounding resistance test instrument for maintenance personnel is the GEOX series double-jaw grounding resistance tester of the Swiss LEM company. This type of ground resistance meter has the characteristics of being able to drive auxiliary ground piles or not, large jaws, high precision, anti-interference, and intelligent. It is completely suitable for maintenance personnel to use when maintaining the grounding of the power room, fundamentally reducing the work intensity during ground resistance testing and improving the work efficiency of maintenance personnel. The lightning protection component tester can use the domestic FC-2G series tester. 5. Other instruments that need to be used in the maintenance process of the communication power supply system In addition to the above-mentioned instruments, there is another type of relatively important test instrument - non-contact infrared thermometer. Infrared thermometers are mainly used to measure the temperature of the main components of the power equipment of the communication system - high voltage, low voltage, and rectifier equipment, such as: high-voltage switchgear, circuit breakers, fuses, cable joints, etc., to avoid equipment damage due to increased temperature. At present, the infrared thermometers commonly used by maintenance personnel are mainly the ST and MX series infrared thermometers of Raytek Company in the United States. These instruments are safe (non-contact), fast, accurate, and easy to operate, which are very suitable for the needs of maintenance personnel's modern maintenance work. In addition, it should be mentioned that in the daily maintenance of air-conditioning equipment, in addition to the multimeter, AC and DC clamp meter, megohmmeter, phase sequence meter, infrared thermometer and other instruments mentioned above, the test instruments needed are temperature and humidity meters, anemometers, tachometers and leak detectors. The instruments usually used by maintenance personnel are the T608/T635 temperature and humidity meters, T415 anemometers, T465 tachometers of German testo company and the TIF5750A gas leak detector of American TIF company. The common characteristics of these instruments are: accurate testing, easy operation, and suitable for on-site office use by air-conditioning maintenance personnel.The maintenance work of the communication power supply system requires not only maintenance workers who love the communication power supply profession and have considerable professional technical knowledge and certain maintenance or management experience in the communication profession, but also advanced and intelligent testing instruments and meters to complement the maintenance workers and make the maintenance work more effective.