Power Supply

Basic UPS Circuit 5V and 12V DC

The above diagram is a basic Uninterupted Power Supply (UPS) circuit. This basic UPS circuit is a very simple and inexpensive.

This circuit can be adapted/modified for other regulated and unregulated voltages by using different regulators and batteries. For a 15 Volt regulated supply, you may apply two 12V batteries connected in series (it will become 24V) including a 7815 regulator (will be 15V stabilized voltage output). There is a lot of flexibility in this circuit.

TR1 has a primary matched to the local electrical supply which is 240V in the UK (it might be various for other countries, 110/120V or 220/240V). The secondary winding should be rated at least 12 Volts at 2 Amperes, but can be higher, for example 15 Volts. FS1 is a slow blow type and protects against short circuits on the output, or indeed a faulty cell in a rechargeable battery. LED 1 will light ONLY when the electricity supply is present, with a power failure the LED will go out and output voltage is supplied by the battery.

The capacity to keep up the regulated supply with no electrical supply relies on the load taken from the UPS and also the Ampere hour capacity of the battery. In the event that you were utilizing a 7A/h 12V battery and load from the 5V regulator was 0.5 Amp (and no load from the unregulated supply) then the regulated supply would be maintained for around 14 hours. Greater A/h capacity batterieswould give a more drawn out standby time, and the other way around.

The complete explanation about this basic UPS circuit, please go to this page.

circuit schematic

View Comments

  • dear sir/maam,
    I am an engg. student and need to make a simple ups as my project . it would be grateful if u please send me an easy to construct and make working ups .

  • please send me a complete circuit and schematic diagram of 12V UPS System and every detail about the UPS.Thank you

  • Dear sir,
    Iam an electrical &electronic student of nattakom polytechnic. I need a circuit diagram for ups of 12v battery . This circuit is used for my project work please send me circuit diagram and details.

  • sir kindly send me the simple ckt diagrams of elt ckts like ups inverter m in dae 3rd year i need an idea to make a project would u like to me sir i,ll be gratfull to you

    thank you

  • Whether an isolation transformer is required technically on incoming and outgoing side of the UPS system? The UPS system (10 kVA) is envisaged for a reverse osmosis plant.

Share
Published by
circuit schematic

Recent Posts

Switched ON Bike Lamp

Do you have a bicycle..? why don't try to build this circuit..?. Powered using battery…

55 years ago

3A Switching Power Supply Regulator

This is the circuit diagram of 3A switching power supply regulator: Simple and cheap, the…

55 years ago

Remote Control Tester

Here is the remote control tester circuit. This circuit is really a simple and easy…

55 years ago

Current Output Multiplier for 78xx Regulator

This is the circuit diagram of current output multiplier designed for regulator IC LM78xx. By…

55 years ago

4 Transistor FM Tracking Transmitter

The following diagram is the FM tracking transmitter based on 4 transistors. No additional notes…

55 years ago

White Line Follower

This is the circuit diagram of white line follower toy. The actuator of the toy…

55 years ago