Lab Bench Power Supply or aka Regulated Power Supply for lab are very much useful in making and testing the circuits. Buying such professional equipment can cost around more than 2000 Rs (Indian Rupee). but you can make yourself a powerful RPS if You have a old SMPS (AC/DC) and a buck boost converter.

There are lot of videos and material on the internet to do this. by inspired from them I have also made one.

.......................................................................CAUTION !!!..................................................................................

230V AC IS USED HERE

THIS POWER VOLTAGE CAN CAUSE INJURY OR IT MAY KILL YOU

IF YOU ARE NOT KNOWING WHAT YOU ARE DOING PLEASE DO NOT TRY

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Step 1: Get Your Compounds

The main compounds that we need is a AC to DC SMPS module. I have taken from my Old computer.it 300W Power rating. The ratings and Wiring details are given in the side of the steel case.

The Other compounds need are.

1) Digital Voltmeter/Ammeter-https://tinyurl.com/nnv77brm

2) Buck Boost Converter- I got only a boost converter with CV and CC- https://tinyurl.com/uwf4h2af

3) 4mm Banana Plug Connectors both male and female 4 pairs

4) Fuse Holder-Tube Type

5) 5A 230v Tube Fuse

6)Potentiometer rotational type- 47K,1K,2K ohm

7) USB type A female dual ports - 2 quantity.

8)Switches 10A, 8A Switch -1,2 quantity.

9)Terminal Strip Screw Terminal Barrier Block 5 holes

10)Alligator Clips 2 Pairs

11) Heat Sink Tubes and Insulation tapes

12)Ply Wood Sheets

13) tool needed- like wire stripper, cutter, paint, sandpaper etc.

Step 2: Hardware Mode

Since the SMPS uses the 230v AC as input and DC as output the body of the bow should be properly insulated so I use 3mm ply wood to make the body.

On the Front and back i make holes and square outlets for cooling fan, switches, USB terminals, potentiometer shaft outlet etc. after cutting the ply wood, placed the SMPS on the base, switches and its cooling fan.

On the front Side, placed all the USB terminals, potentiometer shaft outlet, banana female plugs and voltmeter/ammeter. I use fevicol SH and hot glue gun to secure then in place.

Step 3: Connctions

1) First Identify the colour code of the wire from the ATX/SMPS module. The colour code connector is universal Standard but the number of pins differs on every Module, So please refer the pin details image,in my module there are one 24 pins, two 4 pin and one 6pin connectors.

2) Gather and group them into single output based on the voltage, connect them on the Screw terminal.

It is better to have some loose ground wires because the wiring can be easy.

3) Follow the Circuit diagram in the image.

Note- the Circuit Image is just to get idea of wiring, it not actual semantics.

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The Purple wire denote the Standby, so when the AC supply is given only the +5v purple will be active but not other outputs.

To turn ON the ATX the PS-ON should be pulled to ground. this will turn on the other output pins and also the cooling fan also get turned ON.

Step 4: The Enclosure

After wiring Square up the enclosure by glue and let it dry for sometime.

Since I need to make some changes in future I have not used screws the last piece, it will be like box with opening on the top.

In each step always ensure there is no short circuit and check at each steps.

Step 5: Make Up and Testing

I painted with the light colours so that if any burnt or over heat the colour will easily get blacked.

Using the alligator clips and male banana clips I made probes which will be flexible to use in any kind of circuits.

I have tested with various resistors, led ,motors and short circuit test also. It worked perfectly and no heating problems .all thanks inbuilt short circuit feature of the buck module I have used.