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Uninterruptible Power Supply (UPS): Basic Circuit Diagram

The circuit drawn pertains to a regular industrial UPS (Uninterruptible Power Supply), which shows how the batteries take control during an outage in electrical supply or variation beyond the normal limits of the voltage line, without disruption on the operation providing a steady regulated output (5 Volts by LM7805) and an unregulated supply (12 Volts).

The input to the primary winding of the transformer (TR1) is 240V. The secondary winding can be raised up to 15 Volts if the value is at least 12 Volts running 2 amp. The fuse (FS1) acts as a mini circuit breaker for protection against short circuits, or a defective battery cell in fact. The presence of electricity will cause the LED 1 to light. The light of LED will set off upon power outage and the UPS battery will take over

The circuit was designed to offer more flexible pattern wherein it can be customized by using different regulators and batteries to produce regulated and unregulated voltages. Utilizing two 12 Volt batteries in series and a positive input 7815 regulator, can control a 15V supply.

Industrial UPS are generally categorized as:
Standby – battery backup and surge protection
Line Interactive – variable-voltage transformer and regulates the input AC voltage
Online – supplies all or at least a part of the output power

Tags: Power Supply, circuit, diagram,

Comments on this post:

By james yap 0Score: 

5 years ago:  I like using this especially during crucial times when I have to finish my reports then suddenly there will be blackouts!!! damn electric company!!!

By diffrenece 0Score: 

5 years ago:  what is the main diffreance between in the circuit diagram in the offline ups & the online ups.

By jonas villanueva 0Score: 

5 years ago:  how long will this UPS last and what is the full load that it can handle?

By floyd 0Score: 

5 years ago:  hai, gud day. im doing my project about UPS which can supply two units of computer and have at least a run time of 2 hours long. pls do help me, i badly needed ol ur helps.. Tnx a lot in advance.

By speechlesss 0Score: 

5 years ago:  is it true that it will run for 2 hours?

By muhammad zakir 0Score: 

5 years ago:  Hi good day im doing my project about ups i want use 11 point realy
did this possible pls help ,me thnx

By N.L. GAUTAM 0Score: 



5 years ago:  is it possible to get a simple ups rating 3 watt , 3 volt .

By Khan 0Score: 

4 years ago:  i need a circuit diagram of ups. i m a technician of electronics .i make a a ups so u help me some schematic circuit diagram provide me .

By bajirao 0Score: 

4 years ago:  what is diff.between online and offline ups.

By Dan 0Score: 

4 years ago:  R this the only components the circuit utilizes? Pliz rply.

By Louie 0Score: 

4 years ago:  I'm doing a project right now about extending the battery lifespan of the UPS can anyone help me please... Is it OK to use a Thermoelectric Generator (TEG) that will be tapped into the heat sink?? TEG is a thermo-transducer, will it be enough to generate voltage that will be connected directly to the battery?? i wish someone could help me..

By Prabhu Dev 0Score: 

4 years ago:  Hai gud evening i got a inverter tripping problem last night when EB power failure,we have a 3phase 250kva UPS 3nos parllel connection(each ups have 2 seperate battery banks(1bank 32nos )in series connection),all ups invertors are getting tripped at time no one can gave the battery back up(single minit also)when EB power failure, what is the actul problem ? could u plz help me to give a incident report.

By Kapil Chhaba 0Score: 

4 years ago:  i want to design an offline ups. Can someone send me all d circuit diagrams as i've not found any ckt worthy for my project....

By Anwar Ali 0Score: 

4 years ago:  Mr Louie,
In TEG we use thermocouples for generating small amount of voltage,so be remember that.

By nagendra kumar sah 0Score: 

3 years ago:  i want to produce the small hydro-power station.

By microprocess 0Score: 

3 years ago:  the oscillation of this circuit those not last long. why

By Dharani 0Score: 

3 years ago:  why we use transformer in ups

Avril Cory
By Avril Cory (-1) 0Score: 

1 year ago:  Uninterruptible power supply systems offers to you three distinct types of uninter­rupted power supplies, namely, (1) on-line UPS (2) off-line UPS, and (3) electronic gen­erators.

1. In case of On-line UPS, the battery operated inverter works continuously whether the mains supply is present or not.

2. In the case of Off-Line UPS, the inverter is off when the mains power is on and the output voltage is derived directly from the mains. The inverter turns on only when the mains supply fails.

3. Electronic generator is the same as the off-line UPS system except for one difference that switching time from the mains supply to battery driven inverter supply will not be small (over 10 ms) for the electronic generator. Usually, sealed batteries or lead-acid batteries are used. The running time of these supplies is also low. The de­mand for on-line UPS systems is less than for off-line UPS systems because the price of the on-line UPS systems is higher.

There are nice information's about the ups and power backup supply related.

Thanks for sharing with us.

Best Regards

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