How to choose UPS power supply

Data centers process important information that is essential for the operation of companies and institutions. Therefore, the power demand of data centers must be met 24 hours a day, 7 days a week, but this cannot be fully guaranteed even with the best support power supply. Therefore, there must be some precautions so that in the event of an emergency, the entire data center will not have power problems. Therefore, a UPS uninterruptible power supply must be installed to ensure continuous power supply. Of course, the capacity of UPS is limited, and although it is suitable for IT infrastructure, including computer systems, servers, routers, etc., it cannot be used for heavy equipment such as engines and other appliances related to cooling and air conditioning needs. Obviously, if the data center is running without cooling for a relatively long period of time, the hardware will be easily damaged because the operation of the servers will generate huge heat. Therefore, an emergency generator must also be installed, coexisting with the UPS.

UPS power ratings are in Watts or VA. I would like to point out here that from a purely physics point of view, there is no difference between the two, because: Power = Voltage * Current, or P = VA, the unit of power is Watts, while the units of voltage and current are Volts and Amps respectively. However, the existence of power factor makes all the difference.

Power factor is the ratio of true power to apparent power. True power is expressed in watts, while apparent power is expressed in volt-amperes, and it is this factor that is used to size a UPS. Therefore, when sizing a UPS, simply add the apparent power ratings of all the equipment you plan to power with the UPS.

Simple algebraic summation of the VAs gives you the minimum UPS power rating, but as a rule you should always have at least 20% extra (and possibly more) capacity to accommodate future expansion plans.

The above equations and formulas should tell you the size of UPS you need to use. There are other things that must be taken into consideration, such as cost and the reputation of the manufacturer. Also, check the warranty and repair options provided by the manufacturer to facilitate repairs if problems arise.

Batteries are an important part of the UPS system, so you should also consider whether the batteries are provided as part of the standard supply in the UPS package, otherwise, you will have to pay for them separately. Also check what type of batteries they are, their rating, number of plates, ease of maintenance, etc., as these factors will affect the battery life.

Another point that must be considered when installing a UPS is to always install the UPS system with the help of an expert electrician, as they are well versed in UPS installation and can ensure that the UPS works properly. It may be necessary to do some rearranging of the wires to accommodate the system. Therefore, it is important to discuss with the supplier whether the installation will be provided as part of the equipment purchase agreement or purchased separately.

I have already raised the issue of cooling, considering the length of time that the computers supported by the UPS can run without providing the necessary generator-backed backup cooling system. In addition to the heat generated by the computers and associated equipment, the UPS itself can be a source of heat and noise. Therefore, the mounting location should be chosen appropriately so as not to increase heat problems. If generators are not an option, the main purpose of the UPS is simply to provide backup power for a short period of time, a short period of time sufficient for data center personnel to safely and smoothly shut down the computer systems. Of course, this may not be a very satisfactory approach, but it is possible to allow the computers to be shut down for some time in order to be able to cool properly.

So, we have seen that there are several factors to consider when deciding on the size and type of UPS when installing a UPS system in a data center. Last, but not least, data center management should shop around and compare and contrast the various available systems based on the intended use, including system performance, cost, efficiency, after-sales service and the reputation of the vendor. It is important to be extremely careful when selecting a UPS system, although it may provide emergency power to the data center for a relatively short period of time, as this may trigger the difference between success and failure. If the computer system suddenly stops, we will lose valuable data, information and reputation, which results in failure. Taking the time to seek the best solution is worth the effort, which will increase reliability and reduce the occurrence of downtime, which can be very important and critical to the data center industry.