Battery is the top priority in communication power technology maintenance work-EEWORLD

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The normal operation of the power supply system is the basis and guarantee for smooth communication. The goals of operation and technical maintenance are: to ensure safe, reliable, stable operation and high-quality power supply of the power supply system; automatic withdrawal and withdrawal, accurate and in-place closed-loop control, and real-time and correct reception of instructions and feedback information; to ensure the service life of equipment and reduce the overall operating cost.
In the DC uninterruptible power supply system, the rectifier is the heart, the standby generator set is the key to improving the availability of AC power supply, and the battery is the basis of uninterruptible power supply. The basic requirements for battery operation and maintenance are: to keep the battery in a fully charged state without overcharging, and to discharge more than 80% of the rated capacity when supplying power to the host alone.
The batteries we are talking about here include basic power supply (24V, 48V) batteries, UPS batteries, generator set starting batteries, etc.
Valve-controlled sealed batteries have been widely used because of their outstanding characteristics, but there are still some noteworthy problems in manufacturing and operation. It should always be remembered that it is by no means a maintenance-free battery. For this reason, on February 22, 1994, the former Ministry of Posts and Telecommunications issued Document No. (1994) 108 to all provinces, pointing out that the cathode absorption sealed lead-acid batteries currently equipped with safety valves are not maintenance-free batteries (called valve-controlled sealed batteries), and should not be misled by maintenance-free.

1 Why is the battery the top priority in the technical maintenance of communication power supplies?
From the analysis of the working status, imperfections, and power supply failure statistics of batteries, the technical maintenance of batteries should be the top priority.
(1) If the host equipment fails, channel conversion, wave channel conversion, system conversion, etc. can be performed to ensure smooth communication. Unless the CPU fails, it will generally not cause the entire system to be paralyzed. The communication host equipment requires uninterrupted DC power supply. If the battery alone supplies power to the host, once a fault occurs, the battery reaches the discharge termination voltage in advance and the power supply is interrupted, all the equipment powered by the battery pack will stop working, resulting in large-scale communication paralysis; if the AC is interrupted, the UPS battery will fail, all the billing systems and computer systems powered by the equipment will stop working. When the generator set is started, the battery fails and the unit cannot be started. In short, the characteristics of the communication system determine that battery maintenance is the top priority in technical maintenance work.
[page] (2) Although valve-regulated sealed batteries have outstanding features, such as no acid mist escape under normal circumstances, can be placed in the same room as the host, suitable for distributed power supply and vehicle power supply, etc., there are still some unsatisfactory aspects in terms of production, manufacturing, operation and maintenance. There are two types of valve-regulated sealed batteries: one is a valve-regulated sealed battery (AGM) using ultra-fine glass fiber diaphragm; the other is a valve-regulated sealed battery using colloidal electrolyte. They both use the cathode absorption principle to make the battery sealed. Therefore, there must be about 10% of diaphragm gaps in the diaphragm of the AGM battery. For colloidal sealed batteries, after the injected silica sol becomes gel, the skeleton will further shrink. The viscosity of the silica sol should be controlled at about 10, so that cracks appear in the gel and penetrate between the positive and negative plates. The gaps or cracks provide a channel for the oxygen precipitated from the positive plate to reach the negative electrode. In the production of AGM batteries, pouring too much electrolyte is not conducive to the recombination of oxygen at the cathode, and pouring too little electrolyte will increase the internal resistance of the battery; in the production of colloidal batteries, if the viscosity of the silica sol is too high, that is, too much silicon solution is added, it will cause the gel to have too large cracks, increase the internal resistance of the battery, and vice versa, it will be not conducive to the recombination of oxygen at the cathode. Therefore, valve-regulated sealed batteries have very strict requirements on production processes. Due to gravity and the inability to add distilled water during use, the uniformity of the electrolyte of valve-regulated sealed batteries is poor, and water loss is an important factor in premature failure. Therefore, it has strict requirements on the working environment, temperature, floating charge voltage and charging voltage.
(3) According to statistics, more than 50% of the power supply system failures are caused by battery pack failure or improper battery maintenance. The following are some communication power supply failures we have learned about in the past decade.
In 1992, at ×× Bureau, the low-voltage alarm point of the battery was adjusted too low, and when the alarm appeared, it quickly reached the termination voltage, causing communication interruption;
in 1993, at ×× Bureau, the starting battery was overcharged, the cover was screwed too tight and the vent hole was blocked, and the battery exploded at the moment the oil engine started;
in 1994, at ×× Bureau, the acid-proof flameproof cap of the acid-proof flameproof lead-acid battery had not been cleaned for a long time, and the charging voltage was too high,
so the battery exploded at the moment of discharge; in 1995, at ×× Bureau, the battery had a long-term low floating charge voltage and was insufficiently charged, so it quickly dropped to the termination voltage during discharge, interrupting communication;
in 1996, at ×× Bureau, one group was acid-proof flameproof lead-acid battery and the other group was valve-regulated sealed battery, and the two groups of batteries were operated in parallel, causing one group of batteries to be overcharged and the other group to be undercharged;
in 1997, at ×× Bureau, the 3000Ah valve-regulated sealed battery, with a designed discharge time of 3 hours, could only discharge for more than ten minutes due to the drying of the leaked liquid;
In 1998, several microwave circuits had low floating charge voltage and incomplete batteries, so the discharge time reached the termination voltage very quickly, interrupting communication.
In 1999, the ×× mobile communication exchange bureau interrupted communication due to long-term high floating charge voltage, electrolyte drying, city power outage, and battery failure (during the bureau director meeting). In
2000,

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