Why do UPS power supplies tend to catch fire

1. Improper maintenance of valve regulated sealed lead acid (VRLA) batteries

　　Many people feel that this battery does not require maintenance, after the installation of the battery, it has never been maintained, there is no regular dust removal maintenance. The accumulation of dust is too thick and can affect heat dissipation. UPS batteries are greatly affected by the surrounding working environment, with high temperatures and high humidity.

　　The temperature is too high, which will lead to the occurrence of battery shell deformation, electrolyte leakage, lack of capacity, uneven voltage at the battery end and other problems, which can easily induce a fire.

2. UPS power supply battery electrolyte leakage leads to breakdown in the charging and discharging process

　　There are many electronic devices in the server room, the temperature is too high, the air is dry, it will generate a lot of static electricity. And UPS batteries due to the long-term impact of high temperatures, shell deformation, electrolyte leakage, coupled with static electricity, the most likely to catch fire.

　　The capacity of the whole group of batteries to the condition of the worst piece of battery capacity value, rather than the average or rated value (initial value) shall prevail, when the actual capacity of the battery down to its own rated capacity of 90% or less, the battery will enter the decline, when the battery capacity down to 80% of the original below, the battery will enter a sharp decline in the condition of the decline period is very short, when the battery group has been a great Accident potential, in the charging and discharging process is easy to occur breakdown phenomenon.

3. Battery gas regulator valve failure leads to the occurrence of fire

　　If the gas regulating valve in the valve-controlled sealed lead-acid battery fails, the gas generated during the charging process inside the battery (generally above 2.30V/monomer when charging reaches a certain voltage), the positive pole of the battery releases oxygen and the negative pole releases hydrogen gas which cannot be discharged in time, and when the internal pressure of the battery exceeds the pressure that the ABS plastic shell can withstand, it will lead to the battery shell. When the pressure inside the battery exceeds the pressure that the ABS plastic shell can withstand, it will cause the ABS plastic cover of the battery shell to bulge and break or explode, resulting in a fire.　　

4. Corrosion of internal battery connections leads to short circuiting of the electrode plates

　　The corrosion of the electrode joints inside the UPS battery and the short circuit of the pole plate are due to the accumulation of too much dust on the UPS battery. The dust itself contains various unknown substances which can lead to corrosion and shortening of the joints of the electronic equipment.

　　In the battery pack charging and discharging, the temperature at the contact rises sharply, resulting in a short circuit in the terminal (connection piece), the shell burning melting leading to the occurrence of fire.　　

5. UPS batteries have strict requirements for the working environment

       For example, temperature, humidity, etc., environmental factors can also lead to battery failure, causing fire

　　Experiments have shown that: the UPS battery operating temperature of 25°C on the basis of each 1°C rise, life will drop by 50%. Therefore, timely dusting of UPS batteries to maintain good heat dissipation, very important!

6. Risk of fire in UPS systems connected to converging lines

　　Large and medium-sized UPS power supply system backup battery bank usually consists of dozens or even hundreds of batteries in series and parallel, through the fire case records, the battery bank between the wiring design is not reasonable especially construction is not standardized is an important cause of fire accidents.

　　(1) line overload, grounding, local contact resistance is too large and other faults can lead to overheating of the cable, the insulation layer of the outer skin melting and burning, due to the DC power supply energy is very large, once the problem and failed to find in time, the fire is bound to happen.

　　(2) line leakage or grounding electrical fault occurs, the leakage current is easy to ignite the surrounding combustible materials lead to fire.

　　(3) short circuit, strong arc high temperature effect can make the copper conductor local metal quickly melted, gasification or molten bead splash ignite surrounding combustible materials, intensifying the spread of fire; along with the rapid rise in fire temperature, the adjacent battery shell softening, battery internal hydrogen further leakage, triggering a larger-scale burning of equipment; in addition, as the cable line route has been ignited, the system cable in a continuous jump short circuit, resulting in The further spread of the fire spread.