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Do you know what is UPS? Why is it used and what are the types? If you are a computer user, then you may already know about UPS because it is used in most computers.

But even if there is no complete information, there is no need to panic because in today’s article we will try to provide information in the context of what is UPS. During our daily work, we go through a state of power cut in a lot of time. By the way, other electrical appliances of the house such as Fan, Light, TV, Fridge are not affected much because they do not need continuous power supply.

But if you have a computer system that is useful, then to use it properly, continuous power is always required, in such a case that if there is a Power Cut, then there is a risk of our data loss. Just to overcome this problem, we need a device that can provide us with interruption free power supply. This type of device is called UPS.

This UPS or uninterruptible power supply (UPS) is a device that continuously supplies power to the devices connected with it. If I say in easy language, then it is a surge bar with which a battery is attached.

Even if the power is cut, the battery supplies the power of that need until your main power is restored or the full charge of that battery is used. If you want to know more about UPS then you should read this post UPS completely, because I have tried to provide more information related to UPS as well.

Hope you like my efforts, then let’s start without delay and get complete information about what the UPS does and how it works.

Topic sequence

  • What is UPS?
  • What is the full form of UPS?
  • What is the need of UPS
  • Some important parts of UPS
  • What are the main power supply problems:
  • Types of UPS: –
  • What is the difference between UPS and Inverter
  • What are the benefits of UPS:
  • What are the disadvantages of UPS:
  • Conclusion

What is UPS?

UPS is an electrical device that provides emergency power to a load if the input power source or mains power fails.

What is UPS ?

UPS always supplies power to the load continuously whether main supply is OFF or ON. UPS’s main application is that it supplies power to us in the absence of main power supply so that our device does not have any issues. UPS has its source of energy batteries.

The backup time of any UPS (which means how long the UPS can provide power to the load in the absence of the main power supply) depends on the type and quantity of the batteries used in it.

What is the full form of UPS?

The full form of UPS is Uninterrupted Power Supply. This means that we can use UPS according to an alternative power source that can continuously provide us with interruption free power supply load.

What is the need of UPS ?

As development took place in electronics and computer based devices, the use of sensitive electronics equipment such as personal computers, super computers, data processors, digital controllers, etc. also increased.

Such devices require an interruption free power supply, as these devices use Memories and Processors to handle data. As we know that these devices are very sensitive regarding corrupted power supply.

For example, if you turn off a personal computer directly by removing its power plug, without shutting it down, then you can do data loss and sometimes even your computer’s operating system is corrupted. Can.

In order to solve these problems, UPS is used for Device and Data Safety on Domestic Tor and Industrial Tor.

Some important parts of UPS

If we talk about the important parts of UPS, then it mainly consists of the following parts, about which we will learn later in details:

• Rectifier (Battery Charger)

• Static By Pass or Switch or Contactor

• Battery

• Inverter


As we all know that the main t function of rectifier is to convert AC into DC. It is used to charge the battery and it hangs in the inverter circuit. Its output depends on the load requirement.

There are two main functions of this rectifier. The first is that it is used to charge the batteries, so that the batteries are always in proper float voltage.

Where some manufacturers just trickle charge the batteries to keep them in proper float voltage. At the same time some manufacturers use more sophisticated method (three steps) in which first fast charge is up to 90%, after that slow charge is up to 100%, and finally a turn off charger once this ba The tteries were fully charged then.

At the same time, its second function is that the rectifier is used to convert incoming power from A / C to D / C.

Static Bypass:

Most of the online UPSs have an internal static bypass circuit that works like a first line of defense whenever you experience failure within the UPS system.

Whenever there is system failure, this static bypass automatically turns off the circuit and diverts the incoming power to the rectifier, batteries and inverter so that it can directly load the utility grade power (unconditioned).

Suppose it is not conditioned power, but still it helps in functioning your systems properly if ever the internal components of UPS fail.


This battery is the heart of any UPS system. These Batteries are mainly used to store energy. Remember, if the main power fails in future, then these batteries are used. These batteries mainly use lead and acid. And these are always the reactions in acids.

These batteries also have lifespan and have to be replaced after a few years. The age of batteries ranges from 4 to 6 years. Special care has to be taken of these batteries and distilled water has to be filled from time to time, which helps in the reaction going on in it.


This inverter is the final and main part of the UPS system. It works exactly the opposite of the rectifier process. This means that they convert the incoming DC supply to AC to use the load. It accepts D / C from D.C buss and further supplies it to rectifier and battery.

If ever there is a power failure then rectifier and current cannot provide D / C buss so that power only provides batteries only to the entire system. These batteries continue to provide power to the D / C buss until they become deplete.

Once the batteries are deplete, the system reaches a state of jeopardy and is in search of external power source. Where it is provided with the help of power generator from outside.

The output of the inverter is sinewave. This D.C. Converts to A.C of constant frequency and amplitude.

What are the main power supply problems:

Many types of interruptions occur in different forms in the Mains power supply. These fluctuations can damage our sensitive electronic equipment and data. Therefore, the best solution is to use UPS. Let us know about some such corruptions:

1. Voltage Fluctuations: In Mains power supply, often the voltage increases or decreases, compared to the rated voltage. For example, in our homes the voltage fluctuates from 210 Volts to 240 volts.

We can use digital voltmeter to see these fluctuations. The more these fluctuations, the more damage it can do to our devices.

2. Transient Impulses: The original sine wave of alternating supply can be easily disturbed for any reason due to which fluctuations in amplitude can be seen. These disturbances are also called Transient Impulses.

The instant increase of amplitude is called spike and the instant decrease is called notch.

3. Voltage Surges: When we connect a heavy load to the power supply, then the voltage of the entire system may increase or decrease for some time. This variation is called Voltage Surges.

4. Noise: Distortion in Alternating Sine Wave which comes for short time is called Noise. The main reason for their origin is Radio and TV transmission, or also poor grounding. Noise can cause damage to data and equipment.

5. Frequency Variation: If instantaneous change was seen in the load, then it can cause variation in the supply’s frequency, which can damage the data.

6. Black Outs: If for any reason, if instant failure was seen in the mains power supply then it is called black outs. This is not true for equipment.

7. Brown Outs: If there are Planned power cuts due to overloading of power, then it is called brown outs.

Types of UPS: –

Many types of design are used to implement UPS systems, where all have distinct performance characteristics. The most common design approaches that are followed are:


Line Interactive

Standby online hybrid


Double conversion on-line

Delta Conversion On-Line

The Standby UPS

This standby UPS is the most common type that is used in personal computers. In this UPS, the transfer switch is set to select filtered AC input according to the primary power source (solid line path), and these switches will switch the battery / inverter to a backup source if the primary source fails. Then


This Line Interactive UPS is also a very common design that is used in small business, web, and departmental servers. According to its design, the battery-to-AC power converter (inverter) always has to be connected with the output of the UPS.

When the AC power of the input is normal, then it is operating the inverter in reverse order, so that it is charging.

When the input power fails, then the transfer switch opens and the UPS output from the power battery flows more. Here the inverter is always on and connected with the output, so it provides additional filtering design and produces fewer switching transients than standby UPS. Apart from this, it also performs voltage regulation properly.

Standby On-Line Hybrid

These Standby On-Line Hybrids are also known as “on-line” UPS. This type of UPS is used below 10kVA. In this, the standby DC tDC converter battery is switched on when main AC power failure is detected, just like in a standby UPS.

In this, the battery charger is also very small, as in a standby UPS. Due to the DC combiner having capacitors, UPS does not exhibit any transfer time during AC power failure. This design is also sometimes used with an additional transfer switch so that it can be bypassed by any malfunction or overload.

The Standby-freeUPS

There was a time when Standby-freeUPS was the most used in the range of 3-15kVA. Its design depends on a special saturating transformer that has three windings (power connections).

Its primary power path is starting from AC input, from transfer switch, to transformer, and finally to output. When power failure occurs, the transfer switch opens, and the inverter picks up the output load.

In the design of these Standby-Free, the inverter is in standby mode, and it is energized when the input power fails and the transfer switch opens. This transformer has special “Free-resonant” capability, which provides limited voltage regulation and “shaping” the output waveform.

The isolation which provides Freetransformer due to AC power transients is better than any available filter. Even though it is a standby UPS by design, this Standby-Ferr generates very high heat as it is inefficient from the very beginning. The design of these UPSs is also much larger and heavier than the rest.

The reason for these UPS not being used anymore is that they can be fundamentally unstable when they are working according to the power supply load of a modern computer.

All large servers and routers use “Power Factor Corrected” power supplies that provide a negative input resistance above some frequency range; When combined with a high and resonant impedance Free transformer, it can produce spontaneous and damaging oscillations.

The Double Conversion On-Line UPS

This is a very common type of UPS above 10kVA. It is like a standby UPS, but it has a primary power path inverter in lieu of AC main.

In a Double Conversion On-Line design, the transfer switch is not activated by the failure of the input AC, because the input AC here is not the primary source, but it is the backup source. But this on-line mode of operation shows the transfer time only when the power that comes from the primary battery charger / battery / inverter fails with the power path.

This happens when any block fails in this power path. Here the inverter power also drops out for some time, causing a transfer, this transfer can occur even if sudden load changes or internal control problems arise in the inverter.

Double Conversion On-Line UPS systems also exhibit transfer time, but in different conditions, which is quite different from standby and line-interactive UPS.

Where a Standby and Line Interactive UPS displays a transfer time when a blackout occurs, a double-conversion on-line UPS exhibits a transfer time when there is a large load step or inrush current.

Both the battery charger and inverter convert the entire load power that flows in the design, which increases the reduced efficiency and heat generation.

The Delta Conversion On-Line UPS

The design of Delta Conversion On-Line UPS is a new technology that has been introduced specifically to overcome the drawback of the Double Conversion On-Line design and is available in the range of 5kVA to 1 MW.

Similar to the Double Conversion On-Line design, the Delta Conversion On-Line UPS also always has an inverter that supplies the load voltage. But here additional Delta Converter contributes power to the inverter output.

But when such conditions such as AC failure or disturbances, this design exhibit behavior like double conversion on-line.

If you explain to me in an easy way, the most attention is given to energy efficiency in this UPS.

If this happens then the transfer switch will have to be operated and the load will have to be switched on above the battery / inverter backup. This inverter will start only when the power fails, hence its name “Standby.”

The Line Interactive

The main purpose of a conversion technology is to save this energy.

To do this, they carry energy only in the difference (delta) of the starting and ending points. The Double Conversion On-Line UPS converts the power of the battery and then also reverse, while the components of the power in the Delta Converter move from input to output.

Type Benefits Limitations Our’s Findings

Best value for standby low cost high efficiency compact uses battery during brownouts impractical over 2kVA personal workstations

Line Interactive High reliability High efficiency Good voltage conditioning Impractical over 5kVA These are very popular UPS type in existence because of its high reliability ideal for rack or distributed servers and harsh power environments.

Standby On-Line Hybrid Excellent voltage conditioning Low-efficiency Low-reliability High cost Impractical over 5kVA Line Interactive provides better reliability and similar conditioning in better value

Standby Free Excellent voltage Conditioning High reliability Low efficiency unstable in combination with some loads and generators is its limited application as these are low-efficiency and instability issues and N + 1 On-Line design offers even better reliability

Double Conversion On-Line Excellent voltage conditioning ease of paralleling low efficiency Expensive under 5kVA Well suited for N + 1 designs

Delta Conversion On-Line Excellent voltage conditioning High efficiency Impractical under 5kVA High efficiency It reduces the substantial life-cycle cost in large installations

What is the difference between UPS and Inverter

By the way, there is a lot of difference between UPS and Inverter, so I have explained the difference between the two in detail for your understanding.

Technically, what is the difference between these two Uninterruptible power supply (UPS) where it provides continuous power supply when power is cut. At the same time, the inverter circuit only converts the battery’s DC current to AC and supplies it.

Practically, what is the difference between these two

So let’s know how these two are practically different: –

1. UPS: Uninterruptible power supply (UPS) gives us power when power is cut. It is mainly used in desktop computers according to backup.

2. Inverter: This is a power backup solution. Its total unit consists of three components the charges (which provide electricity to your home), battery and inverter circuit that converts DC battery current into electricity. It is mainly used to supply backup power to the entire house.

3. UPS is mainly used according to the backup of the system. If you connect your desktop computer to it then if there is any power loss then the backup power starts in just 1 microsecond.

4. Inverter is not suitable for computer backup because it has a delay in switching. Due to which computer crash can occur, there is a risk of data loss. Apart from this, it also poses a threat to the motherboard and hard disk.

5. UPS can provide backup for only 10 to 20 minutes. Because its main intention is to provide small time backup so that it can save programs and data. At the same time, the purpose of inverters is to provide power backup to the entire house.

6. Inverter uses flat plate and tubular battery to store electricity. This requires continuous maintenance such as filling distilled water at regular intervals.

Feature UPS Inverter

Where Used Desktop Computer provides backup to other home appliances such as TV Fans lights.

How long does it take to switch Negligible Microsecond

Backup time 10 to 20 minutes 3 to 4 hours depends on the battery

Maintenance has to be watered periodically.

Price from 2000 to 6000 10000 to 40000

What are the benefits of UPS:

– Maintenance of Power – The first and special benefit of UPS is that it controls the power flowing in your computer.

– Continuity of Operation – In this, it is a special thing that it keeps working continuously, which means that even after the power is cut, it keeps doing it continuously and provides power backup.

– Surge Protection – This protects your computer from all kinds of losses from current fluctuation. For this, it controls the power coming into the computer.

– Line Interactive UPS – It flows a balanced controlled power to your computer and even after the current is gone, it gives you so much time that you can save your work. There is no loss of data and device.

– Emergency Power Source: – UPS acts like a very good power source in times of emergency. When Main Power is off, you can use your home power using UPS / inverter. That’s why UPS is a great emergency power source.

– No Data Loss: – Due to unexpected computer shut down, there are all the chances of data loss of the computer. When the UPS is done, the fear of that disappears if the power is gone.

So there will be data loss. After the UPS light is gone, power supplies easily for some time so that you can easily save your data and Shut Down the computer.

What are the disadvantages of UPS:

– Start Up Cost – If you want to use Standby UPS, then it is very expensive for you. This means that the installation cost of UPS is slightly higher in the beginning.

– Infrastructure – UPS is used according to infrastructure. Therefore, the larger the infrastructure, the larger and more battery is used.

– Maintenance Cost – The UPS battery does not work for a long time and after some time it deteriorates, after which you have to completely replace its old battery and use a new battery. With this, this battery also needs maintenance from time to time.


Like we have known that there are many types of UPS and they also have different applications. Hence there is no type of single UPS type which is ideal for all applications.

Therefore, it is very important to know about different types of UPS and their application. Only then can we choose the right UPS for ourselves. Compared to the loss of UPS, its benefits are very high, which makes it special. According to the alternative source of power, UPS is a very good option.

I sincerely hope that I have asked you what is UPS (What is UPS)? Gave full information about and I hope you guys have understood about UPS.

I request all of you readers that you too should share this information in your neighborhood, relatives and friends, so that we will have awareness among us and everyone will benefit a lot from it. I need your support so that I can convey more new information to you.

It has always been my endeavor that I always help my readers or readers from all sides, if you people have any doubt of any kind, then you can ask me irresponsibly. I will definitely try to solve those Doubts.

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