An uninterruptible power supply (UPS) is a device that keeps supplying electricity for a certain period of time in the event of a power outage.
It can protect PCs, hard disks, servers, modems, routers from unexpected power outages, and furthermore protect important data and manufacturing equipment.
How does an UPS continue to supply electricity in the event of a power outage? The structure is actually quite simple.
Imagine an extension cord that you often use in your office or home. It has multiple plugs at the end of a cord that is connected to the power supply on the wall, and sends electricity to the equipment connected to it. It may be easy if we consider UPS as an extension cord with a power storage function.
First, power is transmitted from the power supply to the UPS. Electricity flows straight to the equipment, and at the same time, it is stored in the storage batteries inside the UPS. And in the event of a power outage or other emergency, these storage batteries are used to supply power to each device. This is how electricity is continuously supplied without stopping even for a moment.
There are several types of storage batteries used in UPSs, but lead-acid batteries and lithium-ion batteries are the most common.
Lead-acid batteries are also used in automobile batteries. The Initial cost of installation can be kept low, but the disadvantage is that they must be replaced in about 3 to 5 years.
On the other hand, the initial cost of lithium-ion batteries is slightly higher, but they don't require replacement for about 10 years. As more electricity can be stored in the same volume than lead-acid batteries, the advantage is that the equipment can be protected for a longer period of time.
So, it is expected that lithium-ion batteries will be a main stream for UPSs in the near future.
What is the difference between an UPS and a emergency generator?
The UPS has a built-in storage battery. In the unlikely event of a power outage, it automatically switches to power supply from storage batteries, so that electricity can continue to be supplied to each equipment without interruption. However, the typical backup time is about 5 to 10 minutes, so it cannot withstand a prolonged power outage. The UPS should be used for safe shutdown of the system and as a connection until the generator starts up.
The generator is generally started after a power outage occurs. It takes about a minute to actually generate electricity, so power transmission to each equipment stops during that time. Meanwhile, as long as fuel such as gasoline or light oil is available, power generation can continue, which is effective when a power outage continues for a long time.
UPSs have become indispensable for both private companies and government agencies. Infrastructure of industry and life is full of things that require electricity, such as systems that must be kept running, data related to customers and money, and equipment that will be damaged if the necessary steps are not taken.
An UPS is needed first of all during a power outage that can occur on a daily basis.
For example, a power outage may occur when a plastic greenhouse blown by a strong wind becomes entangled in electric wires, or zinc roof may damage electric wires. Birds may nest on electric wires or utility poles, and wire hangers used as its material may touch the electric wires and cause a power outage. In addition to this, there was also a power outage caused by a ship disconnecting the electric wires passed through the sea. Electric wires connect power plants to substations, substations to substations, and substations to companies and homes. Wherever there is a problem, a power outage will occur.
Of course, Japan is considered to be one of the least prone countries in the world to power outages. However, frequency is not the issue. Even a single power outage carries the risk of system failure and data loss. By using an UPS, it is very important to build a system that does not stop the supply of electricity.
An UPS is also necessary as a backup power supply and emergency power supply in the event of disasters such as earthquakes, typhoons, and fires. Power outages in these cases can last for a long time. The standard backup time for an UPS is 5 to 10 minutes. You will first need to shut down the system and personal computer while the UPS supply power.
However, there are some systems that must continue to operate even during a power outage. In this case, the UPS alone cannot handle the problem. You should use a generator along with an UPS. Companies involved in infrastructure, such as railroads, may have UPSs and generators that can supply electricity to critical systems for 3 to 8 hours.
There are various types of UPS products. There are four main method to supply power: passive standby topology, hybrid topology, double conversion online topology, and parallel processing.
This method has less power conversion loss. As there is slight momentary interruption during a power outage, it is ideal for applications such as surveillance cameras where momentary interruptions are not a concern.
This is a method in which the UPS automatically selects the optimum power supply mode. With high power supply quality and low power loss, it is ideal for control units of machine tools and elevators.
Stable power is constantly supplied through the inverter so it is a method with particularly high power supply quality. In the event of power outage, power can be supplied without interruption. Ideal for base stations and communication servers.
The bidirectional inverter improves the power quality on the power supply side because it compensates the power factor and absorbs noise. In the event of power outage, power can be supplied without interruption. Highly efficient and is ideal for power equipment such as production equipment.
How are UPSs actually used?
It may be easy to imagine that a personal computer must be kept supplied with electricity during power outage. The data stored on your computer may be lost if electricity is suddenly stopped due to a power outage. In the worst case, the computer system itself may be damaged and you may not be able to restore the data.
It is also important to save the data in the peripheral devices of your computer. Especially today, some business operations are based on the premise of being connected to the Internet. Data such as customer management, order processing and accounting are stored in the cloud, and companies are unable to even launch a software without connecting to the Internet. If you need to continue working during a power outage, you will need to use an UPS together with a generator to back up your electricity.
The server stores all kinds of data, such as systems and web-based e-mails. If a power outage causes a system malfunction or data damage, the entire company could be seriously damaged. An UPS is necessary to prevent such a situation.
In these years, a mechanism has been built to ensure data safety by connecting an UPS and a server via LAN. When a power outage occurs, the UPS supplies power to the server. In the event of a prolonged power outage, for example, when the battery level of the UPS drops below 50%, the server can be programmed to shut down automatically and safely. This will protect the system and data in the server.
There are many industries that should use UPSs.
The medical field is a typical example of the need for an UPS. Hospitals have operating rooms, intensive care units (ICU), neonatal intensive care units (NICU), and other medical rooms that are vital to human life. At these sites, there are various medical devices, including patient monitoring devices (biological information monitors). In the unlikely event of a power outage, we could lose lives that could have been saved. It is very important to continue to supply electricity with an UPS.
In addition, although it is hard to imagine, the electricity cannot be cut off at the site where medical equipment is manufactured. For instance, the entire process of manufacturing syringes is kept sterile. If the electricity is cut off at any point in its process, it will not be possible to maintain sterility. As people cannot enter the sterile space, even for the purpose of restoring electricity, the production line has to be kept running using an UPS.
Moreover, it is also important to use an UPS for vaccine cold storage and deep freezers, which must be stored at low temperatures. If the temperature inside rises due to power outage, the vaccine may deteriorate.
UPSs are also indispensable in the financial field. For example, if a bank's core banking system stops due to power outage, not only counter transactions but also ATM and Internet banking transactions will not be possible. Furthermore, if the electricity supply in the data center were to be interrupted, all the data in the core banking system could be lost.
Thus, financial companies such as banks and securities companies have introduced UPSs. Not only so, but each UPS is installed in a different location. A system that can supply electricity in a stable manner is built, assuming even physical damage such as the destruction of some buildings by an earthquake.
You might think that UPSs are not necessary in factories and other production sites as they do not directly deal with human lives. However, there are still some sites where an UPS is necessary.
For example, a grinding machine is used at the production site. It is a tool to finely adjust in micron units all kinds of parts related to human life, such as aircraft engine parts, automobile brake discs, bearings used in motors of home appliances such as personal computers. This grinding machine is controlled by a machine, which processes the object with optimal positioning and force.
What if a power outage occurs while the grinding machine is running? A grinding machine rotating at high speed will lose the proper positioning and force for machining, and the object or the grinding machine may be damaged. In addition, the machine itself may be damaged by fragments of the broken grinding wheel. If this happens, it could result in enormous economic damage.
An UPS is also necessary when using a 3D printer. When you are working on something that takes a long time to make, you may not be able to restart your work from where you suspended. With an UPS, your work will not stop even during a power outage.
In this way, UPS can be used to prevent damage to production equipment and objects, as well as to restart the production process from the beginning. If you decide that you need an UPS after comparing the cost of an UPS with the potential damage caused by a power outage, you may consider introducing them.
Date of publication: July 13, 2021