Make your own Lab Bench Power Supply - DIY - Power your projects - PART 1

in this video I'm going to show you how to build your own variable lab bench power supply it can give more than 100 watts and it has over power protection only when you decrease that output power it switches on these are all the components we need I bought them on the next press I used a metallic case so I had to ground it you can use a plastic one without necessity for grounding it's about 22 and 1/2 centimeters in length and 14 and 1/2 centimeters in width next I decided the position of external components like so I took the dimensions of the switch and multimeter using a screwdriver I assign the place to cut so with the dremel I cut it the case you can do that holding further corners with a nail and then we using scissors cut the case then I rasp the edges then I made a small hole for easier drilling using a screw and the hammer the same for the second one and socket I used a banana socket it's very convenient because you can insert also normal wires in this house so I measure the distance between two leads and board the holes they have to be about one centimeter in diameter [Music] then I inserted the switch the multimeter and the potentiometers [Music] before inserting the banana socket by much attention to the rate very well the leads from the case I used some layers of heat shrink tube like this I inserted this socket and used also hot glue [Music] after I made a continuity test with my multimeter next I took the dimensions of the power circuit and made some marks then I cut the case and inserted the circuit to sign the points to drill [Music] after drilling I fixed in place a socket with screws and nuts the screws were too long so I cutted them then I tried to figure out how to place the internal components sign the place is to bore for grounding also for AC to DC converter and step-down converter then I drilled again [Music] to increase the cooling of the converters I had to increase the airflow and so I made some holes in the case [Music] I use two types of real bits this is the final result [Music] now I had to do this circuit which is in the description and this circuit for the potentiometers of the step-down converter short potentiometers are five four seven K ohms and this circuit is the potentiometers are 10k ohms then I grounded the case to do that I use sandpaper and prepare the place to connect the wire in this way it's a good idea for soldiers in the war to lead to put some solder on the lid and underwire I recommend you to use heat shrink tube and isolate very well the leads of the power circuit and the switch because it's very dangerous using a screw key and screwdriver I fix the ground wire with a screw to the case in this way next I prepared the other leads of the power socket for soldiering then solder the wire the first lead and cut it long enough to solder it to the first lead of the switch and is related the lead I remember to check if the case is grounded so I made a continuity test relative to ground it then I prepared the wire from soldering to the first lid of the switch and saturated after during this of course I is elated the lead I soldered another two wires to the opposite lead of the power socket one of these goes into the terminal of AC to DC converter and another one to the third lead of the switch the second lead of the switch has to be connected for the second quick clamping terminal of the adapter like this before inserting the step-down converter into the case I had to disorder the potentiometers by hitting the leads and pushing the potentiometers out like this [Music] then I soldered small wires to the constant current holes and two to that constant voltage holes [Music] [Music] next I connected the plugs of the multimeter to it I to the small red wire of the multimeter and soldered it with the wire and connected to the positive output of the AC to DC adapter and the other side of the wire to the step-down converter I connected the negative output of the AC to DC with the negative input of the step-down converter then I took clean the wire from insulation like this and connected it here with the help of a screwdriver I made a circle soldiers did a little and connected it with the yellow wire of the multimeter the other side of the black wire was connected to the positive output of the step-down converter the large red wire of the multimeter has been soldered to the negative lead of the banana circuit and the large black one to the negative of the output of the step-down converter then I soldered the wires to the precision multi circle position readers like this [Music] in my case the voltage decreased if I turned the knob of the constant voltage in clockwise direction so I soldered the third lead to the first instead of the second I put a limb parallel with the output a 10k ohm resistor to increase the discharge of the capacitors of the step-down converter the power supply is complete now I can power my electronics projects with voltages I need like I said before the power supply can deliver huge power and work at his maximum for a long time so for example if you want to charge large batteries you will need a cooling system which is in the next video thank you and see you in the next episode [Music]

Channel: ElectroScienceMethod Channel

Views: 188,474

Keywords: lab bench power supply, diy, electronics, electric, laboratory, current, ohm, ohms, wire, wiring, solder, soldering, projects, voltage, variable voltage, current limit, limiting current, cc, cv, variable current, volt, volts, ampere, amperes, home made, how to make, voltage regulation, engineering, science

Id: sirHycTFB9w

Length: 10min 4sec (604 seconds)

Published: Sun Jan 14 2018