Stabilized Adjustable Power Supply 0-15V/5A Circuit

This article for Stabilized Adjustable Power Supply 0-15V/5A Circuit tell us about how to make special power supply circuit.

It can give voltage from 0 to 15V.

Also it can run many electric devices because it give 5 amp current.

One more good thing is this power supply stays stable.

Voltage does not changes much but even if input power is little bit different.

Circuit Working:

Parts List:

Power supply is controlled using P1 potentiometer.

We can adjust voltage from few volts to 15V.

P2 preset control the max limit between 15V and 0V.

To find value of R6 use this formula:

R6 = 0.7V / Imax

Imax is the max current

Example: If Imax is 5A then R6 = 0.14Ω.

When output voltage is low but current is high like 5A power loss can be big.

So it is better to use heatsinks on transistors T1 and T2 to keep them cool.

Formula:

Transistor 2N3055 is used in linear power supply which gives 0 to 15V output and up to 5A current.

2N3055 works like amplifier or pass transistor and it helps control output voltage.

Output voltage (Vout) is set like this:

Vout = Vref × (1 + R2 / R1)

where:

• Vref is a reference voltage which is usually from Zener diode or stable voltage source.
• R1 and R2 make a voltage divider.

Also to control current a resistor is placed in line with load.

Voltage drop across this resistor is used to control base current of 2N3055 transistor.

How to Build:

To build a Stabilized Adjustable Power Supply 0-15V/5A Circuit follow the below mentioned connection steps:

How to Connect the Circuit:

• First connect the input voltage source to LM317 input pin and then ground this pin.
• Put R1 between LM317 output and adjust pins.
• Put R2 between adjust pin and ground.
• Connect P1 between adjust pin and ground too.
• Connect C1 between adjust pin and ground.
• Connect C2 between output pin and ground.
• Put R3 between LM317 output and base of T1.
• Put R4 between base of T1 and ground.
• Connect T1 collector to LM317 output pin and T1 emitter to ground.
• Now put R5 between T1 collector and base of T2.
• T2 collector connects to LM317 output pin and T2 emitter connects to ground.
• Connect C3 between LM317 output and ground.
• Connect D1 between output pin and adjust pin.
• P2 goes in parallel with R5 which helps set top voltage limit.
• Use formula R6 = 0.7V / Imax to find R6 value and install R6 in the circuit.
• If we want to reduce power loss then connect a lamp L in parallel with output.

Testing and Changes:

• After circuit is ready then turn ON the power.
• Use multimeter to check output voltage.
• To change voltage, rotate P1.
• To set max voltage like 15V or lower adjust P2.
• Put good heat sinks on T1 and T2 so they stay cool.

Safety Precautions:

• Before turning ON the circuit double check all wires and part values.
• Watch carefully during first test if something is wrong and turn OFF.
• Be sure about capacitor polarity like positive/negative is correct.
• Avoid short circuits.

Conclusion:

This Stabilized Adjustable Power Supply 0-15V/5A Circuit is made simple.

But always check component datasheets and be safe.

If anyone is new to electronics then ask help from someone experienced.

This kind of power supply is used in labs, workshops, testing places where we need clean, stable voltage for building and testing electronic stuff.

References:

Design and Implementation of Regulated DC Variable Power Supply Using Solar PV with Storage (0-15V, 5A)

Regulated power supply

Datasheet LM IC741