The reliability of the data center power supply system is crucial. It can be imagined that no matter how precise the IT equipment is, how superior the system’s functions are, and how reliable it is, once there is a power outage, even the best system cannot operate. So the importance of equipment maintenance during operation cannot be ignored, which shows that the burden on the shoulders of maintenance personnel is very heavy.
In order to ensure the reliable operation of the power supply system, many places have formulated many good measures. But even so, there are still many loopholes. The reliability of the equipment is already determined after leaving the factory. For example, some inherent deficiencies, such as using aluminum enameled wire instead of copper enameled wire in the windings of power output isolation transformers, are highly likely to cause accidents during full load operation However, statistics show that less than 30% of failures are caused by quality issues with the equipment itself, with 70% of failures coming from the day after tomorrow. That is to say, human error, its manifestation is as follows:
1.Malfunctions caused by improper selection
(1) Basic concepts are unclear and easily misled by manufacturers. For example, in a bidding for UPS on a certain highway, it is required in the bidding document that the UPS should have the ability to continue supplying power without discharging the battery after one or two phases of input are disconnected. Because some manufacturers claim that their UPS does not discharge the battery after a phase failure, and the UPS still has 50% of its power supply capacity; After two phases of input interruption, the battery still does not discharge, and the UPS still has 25% power supply capacity, which extends the service life of the battery. Users think that this performance is good, and it is not difficult to discover its overall problem with a little brainpower: if you want to enjoy its advantages, you must purchase a UPS with 4 times the load capacity, otherwise it will not be able to carry the current load after a phase failure. Speaking of which, what if the UPS disconnects the two wires behind the input switch? Should it be repaired or not? When will it be repaired? Can it be repaired only after a complete power outage? How to solve this series of problems. If users really purchase such UPS according to the actual capacity of the load, this is a huge hidden danger that cannot be solved by operation and maintenance.
(2) Reasons that cannot be explained. For example, some users have been using machines from a certain brand since the last century. At that time, due to objective reasons such as low input power factor, low efficiency, large size, high power consumption, and high price, it was impossible and inconvenient to solve the problem. New models that are much superior to the original ones have already emerged, such as the new high-frequency machine structure UPS, which saves 50000 kWh of electricity per year for every 100 kilowatts compared to the original power frequency machine structure UPS. However, this multi megawatt capacity computer room can save millions of kWh of electricity per year. But for some reason, it is not safe to still include energy consuming machines in the bidding documents without selecting energy-saving equipment, and the structural characteristics of those machines are also included in the bidding documents. This not only increases the investment and footprint of air conditioning equipment, but undoubtedly lays hidden dangers for future operation. This is another problem that cannot be solved in operation and maintenance.
(3) Pursuing low prices. Some users believe that UPS is the same, so they pursue low prices, which leads to malfunctions. For example, a certain highway command center was tempted by cheap prices and installed equipment on the first day, but caught fire the next day; A machine purchased at a low price by a certain life insurance company burned down almost all the input circuits of IT equipment due to UPS failure in less than half a year, resulting in system paralysis; For example, in a megawatt level data center where multiple UPS units are connected in parallel, within a few months of installation, all UPS units tripped due to a power transistor breakdown in one of the UPS inverters.