#1:4 0-30V 2mA - 3A Adjustable DC Regulated Power Supply DIY Kit - Part 4 Amp Display

[@crocellian2972]

I am amazed that anyone on KZbin still admits to having to think. Most all the EE channels are presented by transcendent beings with perfect, infinite knowledge such that they could never make a mistake. You are one hell of a lot more fun to watch.

[@KristianLaholm]

Thank You :)

[@joseveliz6979]

Thanks for the videos. I'm an amateur as well and have put together this kit hoping to add ammeter and voltage meter. After watching a few times it appears the solution is to have a separate circuit (outside of the board) to power the meter this way it does not interfere with the ground and current limiting functions of the PSU. I've read and watched lots of videos on this PSU to the point that I'm over saturated with information. The eevblog has an extensive thread on limitations and mods for this. To summarize: the rectified voltage of a 24VAC PSU (41vcd or something like that ) is higher than the 3 opamps are rated for. So you can upgrade the opamps to make this a true 3A PSU but have to modify other components. The easiest solution is to use an 18VAC transformer which brings the specs more inline with what the current components can handle which is what I am leaning toward since I'm not up to the level of making extreme modifications. I am also considering taking the transistor off the board and add a much beefier heatsink and/or fan from the 24v regulator (could switch to 12v). A beefier heatsink sounds better to me since I prefer less noise from a fan. This is the eevblog thread for those interested in details (www.eevblog.com/forum/beginners/bangood-psu-enhancements/).

[@KristianLaholm]

It's a good kit to start with and learn / refresh electronic knowledge :)

[@4funrc11]

Hey, Genius! :*) Appreciate you taking the time to KZbin this. I'm gonna give it a shot (build) myself and I'm an almost complete newbie. Haha! Anyways, very helpful vid! Well done! Later... :*)

[@KristianLaholm]

Thanks and have fun with the build :)

[@4funrc11]

Kristian_Laholm Hey! :*) Thx for that! Dunno how much fun it's gonna be ÷○ after reading all I have about this PSU. Sheesh! :*) _Change this, add that, omit this, do this, do that..._ Hahaha! Yeah, real fun ahead! :*/ But maybe what I've read pertains to older kits only? *Thx again!* :*)

[@stephanc7192]

Thank you for the video I have ordered the same kit and wants to add V and A meter. Wold have made the mistake to power V and A unit directly from board Luckily my transformer has 6v secondary winding and I plan on adding a voltage regulator to that output from where I will power the V and A meter. Wouldn't it be possible the sense the voltage drop over same resistor on the board? Kind regards

[@KristianLaholm]

You can sense the voltage drop as long as your yolt meter has a high impedance input. And thanks for your feedback :)

[@____________________________.x]

Just cut pin 30 and connect that to the load?

[@alphahr]

7106/7107 have been my meter standby for a few decades

[@zaheerkhan584]

Sir what will be voltage pin 7 and 4 of op ic 1-2-3 ti 081.

[@KristianLaholm]

op1 I don't know need to have a look at the circuit again. op2 op3 are the problematic they have the rectified 24VAC + the negative voltage pump rail and this is close to to 40V and can blow the op.

[@rahulkumar-qu2xo]

what modification in circuit i need to make for 0-60 v ---5a --power output ?

[@KristianLaholm]

That will be a challenge. I'm a amaterur electronic dude so my answers might be wrong. :) The op-amps can only handle 36V rail-to-rail so you need other op-amps if you want 60V. The input diods can only handle 3A and the shunt resistor for the current limit is only 5W (at 5A it will burn of 11W). I'm sorry but this circuit is hard to upscale.

[@gauravshrivastava773]

how can I get pcb?

[@KristianLaholm]

You can find the pcb/kit on Banggood: Power supply: www.banggood.com/0-30V-2mA-3A-Adjustable-DC-Regulated-Power-Supply-DIY-Kit-p-958308.html Current/Ammeter: www.banggood.com/ICL7107-Digital-Ammeter-DIY-Kit-Electronic-Learning-Kit-p-977902.html They are also available on Ebay