Note: The L7824CV voltage regulator I.C. only supplies power to the fan terminals. You could change it to a 7812 Voltage regulator I.C., to supply 12 volts to the fan. With the larger voltage drop on the L7812, it may be advisable to put a small heat-sink on the regulator I.C., but if you are only using a small fan that draws (for example) 0.1 amp of current, then an additional heat-sink may not be needed.
You can replace the 24V regulator with a 12V one. It's only there to supply a 24V fan (odd choice by the way). I haven't even mounted the regulator on my board as I'm using a big heatpipe CPU cooler.
Yes, a good solution also. I prefer to use the small converters as they are adjustable to suit many applications and are more efficient than linear regulators. You can get them for 40 cents a piece now too!
I am so pleased you are not going to destroy your old power supply, if you look on the board you will see the position for the 24v output for the fan and on the board is a regulator for the fan just use a linear regulator of 12 volts for your fan that is what I will do
It still functions and comes out occasionally like all retired things (I still have an AVO 8!). When I think back to all the gear I've scrapped over the years it's a bit sad but don't have space for everything.
Hola, Hice agujeros, como se puede ver aquí: ruclips.net/video/t5N3iKWbSDM/видео.html sobre el ventilador en la parte posterior. El kit es bueno para fines educativos, pero para uso práctico prefiero esto: ruclips.net/video/ikTsE-UGN1s/видео.html Un saludo desde Andalucia.
I actually have that kit. All put together working waiting for some enclosure for like the past year or so ? Someday I'll find one I like. LOL I socketed the IC's. Use to go thru gallons of Carbon tetra-chloride in the military. Cleaning parts with your arms elbow deep in the stuff.
Carbon tet! Used to have a babies bath full of the stuff to clean PCBs. Then went on to trichloroethylene and toluene. And the kids today think they invented solvent abuse!!
I'm interested in how you extended the current limit led out to the exterior of the enclosure. I've looked at the vid 100 times but can't, for the life of me, see where the red and black wires go from the led on the case. Could you put me out of my misery and tell me how you wired the extension? The main point of doing the project, for me anyway, was for the experience. Bench power supplies from China are now very inexpensive so the economics case for building this doesn't really work but I enjoyed all the bits of different skills the job required. I even, finally, managed to cut a reasonably straight line in the enclosure with my Dremel (I had to throw the first case away 🤔). Many thanks for the high quality vid; it's excellent. Subscribed.
Hi, If you pause the video here : ruclips.net/video/t5N3iKWbSDM/видео.html You can see the large capacitor with 2 diodes at the bottom of the board. Look at the negative end of the second diode and you will see the clear LED just above and to the right next to an orange capacitor. Later I decided to unsolder the LED and mount it on the case which made more sense to me!! Thanks for watching, have a great day!
Thanks for this. I just ordered one of the copies. Now that I know the original is Banggood, I may order that one too. My only issue with the kit is be that 3 amp o/p is a little small for my application. I need about 4.5 amp max. Is there's a fix for that - to get more than 3 amps out of the circuit? - such as: using : -- 2 output transistors in parallel. -- Instead of 2 is there another fix to use a higher rated o/p transistor? PS: You never said what the AC ouput of your trasnformer was. Presumably 24V AC? Excellent - all round tutorial.
Hey thanks! I would only build this as an educational project not for "serious" use. It's an old linear design. If you want a supply for your DIY projects this is a better option : ruclips.net/video/ikTsE-UGN1s/видео.html Have a great day!
For accurate V/A meter must to feed the meter itself from different small supply. One can change meter's little trimmers with multi turn trimmers. Then will be 10mV accurate. Drill the box! Cheers!
the fan will work quite happy on 12v too. 7 bucks on "bang good" for that money it looks a grand little kit,,, oh think I just realized that you didn't have a 24v fan.. but if you did 12v would run it too... question.. would you give this kit a thumbs up or down now that you have it a while now???
As an educational kit for learning electronics and assembly highly recommended. As a bench power supply it is OK but if you just want a supply there are better options.
Good afternoon, I bought a 24 + 24 3A transformer and when connecting and measuring with a multimeter I saw that the output voltage is 25v, I would like to know if I can connect this board with this Trafo?
Obrigado Michel! You do not say if you are measuring AC or DC values, I assume AC. It is not unusual for the "off load" voltage of a device to be a little higher than when in circuit so 24 - 25 volts AC is OK. Remember that the DC voltage produced when the AC is rectified and smoothed will be 1.414 times higher i.e. 24V AC = 34V DC so 25V AC = 35V DC. The input components, most importantly the capacitors are rated at 50 volts so I do not see any problem using that transformer. Tell me how it works out. RUclips no longer shows me if you are subscribed. Please consider subscribing if you have not done so already!
@@1nformatica Good afternoon, I am referring to 25V AC from the transformer output, as the kit board asks for a 24V ac input and my transformer is outputting 25.5V AC, I was in doubt if I could use this transformer, thank you very much for your help, you do you know what the input tolerance of this board is? I'm already written on your channel. When I finish setting up I say how it works, I'm using google translator disregard any writing errors.
@@michelluizvalente7024 Looking at the circuit diagram I would guess that it could tolerate an input of up to 30 V AC. 25.5 V AC should be no problem. Do not forget to put an insulating washer on the output transistor. Remember that this is an analogue power supply and not very efficient meaning it will get hot! Do not run it at high (+3 Amps) for long periods! Good luck with your project.
@@1nformatica Thank you very much for the information, for the output transistor I will use a heatsink with a cooler, this power supply that I will build and more for testing, if it is really good I will build a more powerful one, and again thank you very much for your help.
Thank you for the Video very good you are taking me back with your description I have the same tap wrench but mine is English and the circuit is a copy from electronics website so all copied from England when we made everything those where the days, Glad you did not destroy your power supply. I am contacting you in the hope you would know the board dimensions as I have ordered one from China
Hi Bob, Yes happy days. I had the privilege to work for a while in a truly old fashioned Company. They had everything under one roof. Design, Model Shop, Mechanical Fabrication, Electrical & Electronic design and assembly. Goods inwards inspection and of course "Norman" the storeman who you had to keep on the right side of if you wanted anything quick! The PCB is approx 80mm Square. The box I used was 180x110x90 RS part number 220-440 enjoy! Hope you've subscribed and check out my Oscilloscope build ruclips.net/video/zNTXAwxTG0w/видео.html
Hello everyone: This circuit is quite good but the power transformer should not exceed 20V. The DC voltage in the supply (+ Vdc, -Vdc) in the operational ones when setting the 24V voltage exceeds the maximum values for which the manufacturer designed it. The maximum data sheet voltage says + Vcc - (- Vcc) = 36V, recommended 30V. It may work well for a while and then the operational ones will burn.
The circuit diagram is in the instructions you can download here : img.banggood.com/file/products/201505080459530-30Vinstall.pdf The fan has it's own regulator 7824 for a 24 volt fan. You can change this for a 7812 regulator for 12 volt fan if you want. A voltmeter is simply wired across the output terminals. Thanks for watching, have a great day!
Thank you for your clear and informative video. Just the right balance between the construction process itself and the technical background, and good to hear that you were taught how to solder properly as well! I have just completed a Banggood kit and have a problem that the current limit LED is illuminated even when voltage and current controls are fully wound anti-clockwise [to zero]. I checked individual component values as I assembled the kit and tested each semiconductor and Op-Amp as well. I am hesitant to leave the PSU powered up for too long in case a fault causes a burn-up so I have not got as far as using the trim pot to zero the voltage adjustment or current control. Do you have a note of the stand-by or quiescent current consumption of the PSU off -load? If I could be sure that I am in the right zone with that I could do some other voltage checks to see if I can locate the problem. I don't have a proper AC ammeter, but monitoring the AC voltage drop across a 100 ohm resistor suggests a stand-by current of about 50mA at present. [I have not yet fitted the fan and its associated regulator]. I would be grateful for any advice.
Thanks for commenting. Double check the power transistor is isolated from the heatsink ruclips.net/video/t5N3iKWbSDM/видео.html I didn't take any quiescent current measurement I'm afraid. Also check for any solder bridges or dry joints. If the problem still persists then you'll need to start removing some components working back from the output stage until the short goes away. Good luck!
Great informative video. Electronics is my hobby but I am still a nubby. I purchased one of these kits but ran in to a couple of problems. The regulator supplied was a 7815 which I did not realize at the time was only for the fan so could have used a 7812. I carefully checked all components before assembly but missed one crucial one which happened to be the 0.47 ohm 5 watt resistor. The supplied resistor was a 47 ohm and without realizing it I installed it. On turn on the output trans and resistor became extremely hot so shut it down and that's when I found the wrong resistor. On replacing the resistor I turned the PSU back on and the 0.22uf MLCC capacitor exploded. I am now waiting on a delivery of replacements but do you think I may have shot any of the other components. I also want to change the 24 volt supply to DC and intend removing the IN5408's and wire the DC input direct to the 3300uf 50 volt cap. Will this work without changing anything else? Your assistance will be appreciated
Thanks for the comment. Seems like you had some bad luck there, I am surprised the resistor caused such a problem. It is impossible to say if other damage was done, you will have to try it and see! Maybe put a simple current limiter i.e. lightbulb in circuit : www.instructables.com/Light-Bulb-Current-Limiter/ Putting DC into the unit is OK, just remember you will need 24 * 1.414 = 34 volts DC for full output. Although this is an interesting project to build it is not a very efficient design being analogue. I will be making a video on a very versatile and inexpensive Switch Mode PSU for hobby use soon. RUclips no longer shows me if you are subscribed. Please consider subscribing if you have not done so already!
@@1nformatica Thanks for the quick reply. I have noticed that there are two versions of this PSU. The layout on the second from Banggood is much better but the circuit appears to be the same. The assembly and testing instructions are actually for the second one not the one you and I have assembled. Thanks for the heads up on the power requirements for using DC instead of AC.
The connection diagram is here img.banggood.com/file/products/201505080459530-30Vinstall.pdf Connection for the Amp / volt meter here www.banggood.com/Dual-Red-Blue-LED-Digital-Voltmeter-Ammeter-Panel-Volt-Gauge-Meter-p-918687.html?akmClientCountry=ES&p=NL2203782949201409M4&cur_warehouse=CN#customerQA
I am returning again after 3 years since building the Pcb only to complete it with a new transformer and an enclosure . One question please how to get a specific constant current for example I need to charge 18650 battery with as little as 150 mA at 4.2 volt , setting the voltage is easy but how to set the maximum current ? Thanks again
This is a very basic supply and you would have to calibrate the current setting yourself. To do this place your ammeter across the terminals and set the dial to the desired current value. Then mark the dial at that point. This will not be very accurate or repeatable due to the analogue potentiometer. I would not use this supply to charge cells / batteries especially Lithium Ion as overcharging may lead to explosion and fire!! LiPO cells should never be charged unattended. A much better supply for your needs is this one : ruclips.net/video/ikTsE-UGN1s/видео.html
Hi, I built the same kit a short while ago and used the same system for powering the fan and the display. Everything worked until, unfortunately I made a short circuit with the output cables, now the voltage regulation no longer works, it always remains at maximum. Short circuit protection was indicated in the description but this is probably not the case. Now I have to go find what may have broken. Some idea?
Did you set the current limit as here : ruclips.net/video/t5N3iKWbSDM/видео.html First port of call for you would be to check the output transistor, it is probably short circuit. Good luck! Thanks for watching, have a great day!
Very nice and informative video. Many thanks. I am considering buying this DIY kit myself. But meanwhile, I have seen at least two videos with some discussion about heat development in the power transistor. So I am getting a bit reluctant. Could you kindly help me with these three questions as follows: 1. Does the kit come with a legible circuit diagram? 2. In your video, if I read that correctly, I saw the secondary side power rating of the transformer you are using as 37.5VA @24V. Is that really 37.5VA or actually 375VA? If it is 37.5VA, how can it deliver 30V @3A? Probably I read something wrong. Could you clarify this, please? 3. In your video, you are using a buck converter to generate 12V for the fan and the VA meter. Could you please give the part number and/or vendor of the buck converter, please? Thanks a lot for your help in advance.
Hi If you follow the link in the description to the kit you can download the manual including circuit diagram. The transformer is this one : uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/ There are 2 windings making 75 VA @ 24 volts ac. so 24 * 1.414 gives 34 volts DC max is about 2.2 Amps. The buck converter is similar to this : bit.ly/DCDCBuck Please consider subscribing if you have not done so already!
Thank you for a very clear and concise video, and I especially appreciate your excellent diction. I have built the kit using a few mods I found and all was well until I started to connect an 8.5 amp Variac. Since I already had the Variac I was happy to not have to buy a 24 volt transformer. I am very much a novice whose only experience was limited to a general class ham license back in the early 60s!! As a result, I am totally confused on how to connect the 2 leads from the Variac to the 3 connections for 24 vac shown on the board! If you have the time, could you or anyone explain to this simpleton how to accomplish this---assuming it can be done? Does it have to do with earth ground, and if so, which lead as no polarity is shown? It has me frustrated, embarrassed and humiliated! Thanks so much for any help
Only the outside 2 connections are used and you can see the connection to my transformer here: ruclips.net/video/t5N3iKWbSDM/видео.html As it is AC there is no polarity just connected the variac to those connections. Make sure before connecting the variac is set correctly!
@@1nformatica You have made my day! Thanks so very, very much for making clear a solution to a simple problem my lack of knowledge had blown way out of proportion!
awsome vid bought the kit myself can i be so bold as to suggest replacing the stock 10K pots with10 turn pots it will improve the precision of the device
Hi Federico, thanks for the comment. Yes, very good idea with a multiturn pot it would be easier to set the voltage accurately. Check out my other kit builds for an Oscilloscope : ruclips.net/video/zNTXAwxTG0w/видео.html and Geiger counter : ruclips.net/video/4Tqo3B98ZgM/видео.html
Here you are : Mini DC-DC Converter Step Down Module bit.ly/DC-DC_StepDown LED Digital Voltmeter Ammeter Panel Meter bit.ly/VAPanelMeter Hiland Heat-Sink +Cooling-Fan bit.ly/Fan_Heatsink Please consider subscribing if you have not done so already!
Thank you for such an informative and well-done video. I have just finished this kit and it immediately blew my 3A fuse. I am currently following your suggestions elsewhere in the video to find the fault(s). But I do have a question I believe you can help with. Do I need to have an insulator between the 7824 regulator and the D1047 transistor and their heat sinks? I did use a conductive grease. I have read that sometimes an insulator is required but of course that would depend on the circuit. Any help is appreciated!
Hi, thanks for the comment. The transistor does need to be insulated from the heat sink. The regulator needs no insulator as the centre tab is ground. Hope that solves the problem!
From the instructions "Please make sure that you have installed cooling fin of considerable size on Q4 (D1047) before starting the power, _ and the cooling fin should be insulated from the circuit _."
I have built a number of these kits but now I'm trying to wire an ebay special amp/volt meter but I dont know where to wire the large red wire from the current . I'm using a 24 vac transform step down from 110ac can you help with possibly a schematic showing the power supply as I'm not very fluent with wiring schematics. I am teaching myself these thing via youtube lol p.s my problem is where i understand that these amp/volt meters have to be wired up funny if trying to measure volts and current from the same source where I loose track is that my source of power is 24vac where do I hook the large black wire from the amp meter if I'm hooking the power (red) and sense (yellow) to the positive of the load and the positive of the amp meter (large red) to the neg of the load leaving the ground of volt meter (smaller black) un soldered, when in this scenario the larger black amp wire is to be soldered to the positive of the current source. Where this power supply is sourced by ac I'm stumped and therefore have no reading of the current in which can be adjusted with this kit.. Can you help? If so please email me @ Stangreer8792@gmail.com I can then email you pictures of my components and supply as a whole thank you
on my power supply The rheostat does not change the voltage value, and the maximum voltage I can reach is 25V (THE 82 OHM AND 220 OHM RESISTORS ARE HEATING) can someone help me?
Check that you have the main power transistor insulate from the heatsink. Otherwise double check all you wiring and solder joints. Good Luck. Feliz Natal!
I brought 30V 3A DC Regulated Power Supply Kit and LED Digital Voltmeter Ammeter Panel Meter, all components soldered and it worked well but when I connected LED Digital Voltmeter Ammeter Panel Meter I probably shorted out now I get input and out 30V with no regulation on pot voltage, where to locate the fault have I blown a IC or zener diode?
Hi Joe, I would check the output transistor for short circuit first using a multimeter or transistor tester if you have one. The circuit diagram is at the end of the assembly instructions you can download from the product link : bit.ly/PSU_kit If you don't find the problem I would start troubleshooting from the input ac forwards and test each stage. Good Luck!
Problem rectified..you were spot on, Found fault with transistor 2SD882 which I replaced with BD139 now it works good. Thank you very much for your prompt guidance.
Good news Joe!! Glad you got it fixed. Take care you don't use it at high currents, the BD139 is only a 1.5 Amp transistor with 3 Amp peak rating. A little close to the edge!
Thanks...2SD822 was not available so I used DB139, I used my multi-meter to check peak amps output at 30 volts I only get 2.64 amps so it should be fine , But I will keep in mind not to exceed 1.5 amp..This was my first major project completed with not much basic skills in electronics apart from soldering..smile ..and at 62yrs. I'm thrilled to solve a problem with your help and guidance...Thanks once again take care God bless.
Thank you Joe. I'm only 2 years younger than you and just starting to learn CNC! Check out my playlist for Electronics projects aimed at beginners: ruclips.net/p/PLxtbRS-naT6_7U7svrrTfRsy9Prhpx3iC Feel free to ask any questions or suggest projects you would like to see me build. Cheers!
Got mine all soldered. The voltage works fine but when I turn it on the current is saturated to the max. I v checked for short circuit, can't find any. There is no load but the current limiter is on. Any idea?
@@guillaumelombard7210 Do you have a panel meter for current wired in? I have seen some panel meters with different coloured wires and it is easy to get confused.
@@1nformatica it s bare, I removed all external component that could be causing trouble. I m thinking of swapping the power transistor as I cant think of anything else that could draw that much power (other than a short circuit)
@@1nformatica Hi, Sorry for the confusion. On the PCB there is an LED installed that illuminates when the circuit is 'in constant current limit mode'. Towards the end of the video it appears that you have removed the LED mounted to the PCB and replaced this with a panel mount LED, so that this function is shown on the outside of the enclosure (to the left of the digital VA meter display).
The fan is fed directly from a 24 volt regulator, it should be on all the time. Check you have + 24 volts DC on the pcb connector. Please consider subscribing if you have not done so already!
Hi, much depends on the transformer you have. Check what the voltage is on the circuit board after the bridge rectifier, that will be your max output voltage.
Yes, it has a current limit you can set. Do not leave it connected to a short circuit for long as the supply will overheat, it will need a good fan and ventilation. Please consider subscribing if you have not done so already!
have you tried with a load that absorbs 3A? Is the heatsink of the power transistor in the video sufficient when we have low voltages and high current?
I do not use it for high currents. There is a cooling fan and I cut holes in the box to help with cooling but it will still get warm as the design is very basic. At 3 Amps I would not use it for long periods.
Hi. Realy nice video. I soldered exatly same kit. But got a problem is no reaction to pot regulation. And is noting on output. And is no -5.1v betveen ic pin4 and r3. Electronic is like my hobby. But i not strong enought to sort that. I understanding schematics but canot read or trace how the components effects etch other. Hope you can help.
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
@@1nformatica thanks for advice. Wuold do. I found some parts its not soldered trough the board. Some clear of soldering in the opposite of board. May that be isue to. Wuold add some flux and resolder every joint.
hey i have a Problem, i have the same board and used an led plug (24v) for the input but it doesnt work. when i measure the input voltage it was 31v (idk why, also doesnt change when potentiometers are turned) und the output voltage was -0,59v. Is my board fried? While the ac plug was connected nothing really got hot so i have the hope that nothing is broken. the led was also always on but idk why. Im a electronics noob and wanted to do some projects with it so i hope you can help, thanks.
I do not understand what you are using to power the board. You should use a transformer like this one : uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/
@@1nformatica hey im using smth like this www.ebay.de/itm/Netzteil-24V-AC-Wechselstrom-IP44-f-r-Au-en-6W-50Hz-Konstsmide-Trafo-Driver/254743551310?mkevt=1&mkcid=1&mkrid=707-53477-19255-0&campid=5338364442&customid=254743551310_159912&toolid=11000&pageci=50e66d82-01e6-4d61-b2c0-2ceac79db5a1 because i didn't had a transformator that you send.
@@MrAnimeAmv1 That device cannot supply sufficient power. You see it is 6VA or 6 Watts. Power = Volts * Amps so 6W at 24 volts is only 250 mA. You need to find a transformer with at least 75 Watts as the one I showed you.
I'm building one of these PSU kits now, I'm going to replace the 24v regulator with an LM7812 regulator. I've had the idea that if I use 2 secondary transformer I can have a switch to select where I tap it from. So if i'm only using below 15v say, I can just select 1 secondary coil reducing the input to the kit to a voltage that the transistor can cope with., (I'll need 15v min for the 7812 to operate ). Ive seen a video where he only had a 12v supply at the time & it still worked. What do you think?.
The 24 volt regulator is only there to power the fan. I am sure if you reduce the AC input voltage it will work but obviously be limited in it's output voltage. I do not see a reason to do that. Better to find a 24 volt AC transformer.
Sorry, I think you misunderstood me. The LM7812 input voltage max is 35v, if the voltage at the input to the 24v regulator is less than this you can replace the 24v regulator with the LM7812 regulator. The idea of switching the tapping point on the secondry coil is so if you are only wanting a lower voltage say 15v dc, then you can switch to tapping just one half of a dual secondary, the power transister wouldn't have to work so hard. I believe that some manufacturers of PSU use this technique.
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
Great video! Very curious to see how you tapped into the 24V line on the board. One question form an amateur: in this configuration do you need the board's 24V voltage regulator at all? Can't you just leave it out, solder wires onto the holes where it was supposed to go, and then take those wires directly to the small step-down converter that you use?
Hi, I just tapped onto the +24 volt connection that is for the 24 volt fan. You're right the regulator is not really needed. I think I assembled the kit before I realised I did not have a 24 volt fan! Doh!!
Hello I would like to know how it is possible if it is possible to use this power supply only for 15 volts and only 2 Amps max or 1A it's for the third way of my double channel in DIY Thanks a lot
Sure, no problem. The transformer I used is only 75VA uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/ I don't tend to use the supply at high currents.
@@1nformatica Thank you. I don't think it would handle long term high current draw very well anyway, not without some heavy duty active cooling and a massive heatsink. And thanks for the video!
The trimmer is to adjust the output voltage zero point as I show in the video ruclips.net/video/t5N3iKWbSDM/видео.html You can download the assembly and calibration instructions from the product web page bit.ly/PSU_kit
Good day sir After assembly the circuit out not getting stable initially goes to max voltage and then back to 1v Checked all components One ic u2 getting hot when increasing the pot but in output no voltage I used 24v ac input Pls help me
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
Sir i am trying out this board and facing problem. When i power it on, the 24v output is on and fan is running but output voltage remains 0.05 to 0.1 volt when rotating the 10k pot.Also tried Trimmer in pcb calibration but not worked though. I am using a 24-0-24 v ,2 Amp transformer except 3Amp(As its not available here). Sir please help to sort it out.
Start by checking every component is placed correctly. The resistor colour codes can be difficult to read so check them with a multimeter. Check diodes are correctly polarised and IC's the correct pin 1. Check the soldering for any missed / bad joints. If you find no error then the circuit diagram is in the instruction manual and you will need to follow it to diagnose the problem. Good luck!
The pdf manual is the only one I think. It has the adjustment procedure and the circuit diagram on the last page. 99% of problems are from incorrect assembly, as I said before double check everything. The circuit is relatively simple and if you do not understand how it works then now is time to learn! If there is no one near you that can help you (local college / university, repair shop) then Google is your friend to find the data on each component. Good luck!
Not easily. You could change the output transistor for a higher amp and use a bigger transformer. But is is a linear design and not very efficient. A better solution for a bench power supply is this module ruclips.net/video/zfkcfn-hCmg/видео.html matched with an inexpensive switch mode PSU would be good.
Hi Daniel, thanks for the comment. I did put holes in the top of the case for air flow and made sure the fan was set to blow air out of the case. I should have made that clear in the video so thanks for pointing that out. Best regards.
I have built the same kit. I enjoyed it very much. thank you for the video! I added a dual volt and amp meter, but on my meter the ground to the volt and amp meter and common. Therefore I had a problem powering it from the board like you did. Are yours the same or are the negative to the amp meter and volt meter separate? kind regards
Hi Stephen, It's a nice kit. The Volt / Amp meter ground is common on the meter I used as well. You can see the wiring on this link: forum.banggood.com/forum-topic-47750.html
Thank you very much for your response. I enjoyed the video! I'll recheck the influence of the meter on my circuit. I know that the 7824 (voltage regulator) provides no isolation. I presume neither does the buck converter (so the neg on the output of the buck converted it common to the neg output terminal of the kit). What do you think? Kind regards Stephan ps: At first I was wondering why you opted for the buck converter and didn't change the 7824 to a 7812, but your answer to +Laziter73 made a lot of sense. The buck converter is a lot more efficient that the linear converters. Did you power the buck converter from the rectified point or via the 7824?
Hi Stephen, Yes the buck converter ground is common to the supply. It was connected to the 7824 output. Check out my favorite kit build so far ... ruclips.net/video/zNTXAwxTG0w/видео.html
sir i bought this kit and the same display you are using and when i connected the display with it i lost the current control feature but when display is not connected i can actually control the current with voltage . sir when i connected this display with this board ten even if current pot is at zero and i increase voltage current keeps increasing even the the current pot is at zero so i tried to measure in different ways and at the end i connected +ve of ampere meter to +ve of output of board and -ve to -ve output and connected load with and it get short Circuited and i killed the board for now, sir i ordered a new one it will arrive in a week , please tell me what i am doing wrong what i need to do?? please help me out
The wiring of the meter is confusing and the colours of the wires can change depending where you bought the meter from. My example has black, green and red wires ( as well as the red and black thin wires for power to display). The main "thick" wires are connected as follows. Red goes to the positive output of the power supply. Green goes to your negative output socket NOT the power supply output. Black goes to the negative power supply output. There is a separate red wire from the positive power supply output to the front panel positive socket. Also see this information : forum.banggood.com/forum-topic-47750.html Good luck!
sir yesterday i bought a new one and the problem is same when i remove current shunt of display and i connect a motor at the output of power supply everything works great and i can limit the current with current potentiometer but when i use current shunt of display to read the current it reads current well but it creates a problem and that is if even my current potentiometer is at zero still if i increase only voltage then current also rises even current potentiometer is at zero i don't know what is wrong with it sir please help , i bought a new display and a new power supply board because i thought previous one was not working fine, so please help me out.thanks in advance
1nformatica Wow! You're certainly 'one of the good guys' of RUclips! ÷*) Being an absolute beginner, my _current_ projects are limited to R/C aircraft (LEDs/Autonomous flight/PWM and serial control/etc.) related stuff. And, I'm new to a lot of the lower-level workings of those, too. LOL! A real beginner I am. But, hey! I'm willing and determined to learn as much as I possibly can. ÷*) Hmm... What would I like to see you build next? Oh my! How utterly thoughtful of you. _Huge THX!_ May I take a rain-check (so to speak) on that subject, just for a short time? I'll be giving it some serious thought, I promise. Albeit, when my kit arrives, any day now, I guarantee I'll have a question or two. Nothing to badger and burden you with. I can figure out most things on my own. By the way, in the unlikely event RUclips hasn't/doesn't notified/notify you, I've subscribed. Oh, yippee! Right? ÷*)
Aw shucks! Thanks for subscribing and feel free to ask any questions. Remember there are no stupid questions only stupid answers! I have the autonomous flight bug now having bought a Hubsan H501S ruclips.net/user/edit?o=U&video_id=n2W37DzzmYQ I have an Ardupilot APM 2.8 Flight Control Board here waiting my attention.
Dear Mr/ @@1nformatica I will definitely return back to you..after receiving my item I apologize for many of my questions ,when we enjoy loving those who helped us.it's a virtue !~(^_^)~ Thank you very much
Agreed, this linear design is not the most efficient and will get hot at higher currents if not properly cooled. However, as an educational kit it suits its purpose well. Haben Sie einen guten Tag!
![KSI - Dirty [Official Visualiser]](http://i.ytimg.com/vi/VoDh1h1dPUE/mqdefault.jpg)
Very informative will help both pro and fresh starters alike.
Hey thanks! Have a great day!
Note: The L7824CV voltage regulator I.C. only supplies power to the fan terminals. You could change it to a 7812 Voltage regulator I.C., to supply 12 volts to the fan. With the larger voltage drop on the L7812, it may be advisable to put a small heat-sink on the regulator I.C., but if you are only using a small fan that draws (for example) 0.1 amp of current, then an additional heat-sink may not be needed.
Hi Jim, thanks for that. If I build another one I may do it that way.
You can replace the 24V regulator with a 12V one. It's only there to supply a 24V fan (odd choice by the way).
I haven't even mounted the regulator on my board as I'm using a big heatpipe CPU cooler.
Yes, a good solution also. I prefer to use the small converters as they are adjustable to suit many applications and are more efficient than linear regulators. You can get them for 40 cents a piece now too!
I am so pleased you are not going to destroy your old power supply, if you look on the board you will see the position for the 24v output for the fan and on the board is a regulator for the fan just use a linear regulator of 12 volts for your fan that is what I will do
It still functions and comes out occasionally like all retired things (I still have an AVO 8!). When I think back to all the gear I've scrapped over the years it's a bit sad but don't have space for everything.
linda fuente de alimentacion, creo que iria bien hacer algunos agujeros para la circulacion de aire.
Hola, Hice agujeros, como se puede ver aquí: ruclips.net/video/t5N3iKWbSDM/видео.html sobre el ventilador en la parte posterior. El kit es bueno para fines educativos, pero para uso práctico prefiero esto: ruclips.net/video/ikTsE-UGN1s/видео.html Un saludo desde Andalucia.
I actually have that kit. All put together working waiting for some enclosure for like the past year or so ? Someday I'll find one I like. LOL I socketed the IC's. Use to go thru gallons of Carbon tetra-chloride in the military. Cleaning parts with your arms elbow deep in the stuff.
Carbon tet! Used to have a babies bath full of the stuff to clean PCBs. Then went on to trichloroethylene and toluene. And the kids today think they invented solvent abuse!!
@@1nformatica We had fire extinguishers charged with the chit.
I'm interested in how you extended the current limit led out to the exterior of the enclosure. I've looked at the vid 100 times but can't, for the life of me, see where the red and black wires go from the led on the case. Could you put me out of my misery and tell me how you wired the extension? The main point of doing the project, for me anyway, was for the experience. Bench power supplies from China are now very inexpensive so the economics case for building this doesn't really work but I enjoyed all the bits of different skills the job required. I even, finally, managed to cut a reasonably straight line in the enclosure with my Dremel (I had to throw the first case away 🤔). Many thanks for the high quality vid; it's excellent. Subscribed.
Hi, If you pause the video here : ruclips.net/video/t5N3iKWbSDM/видео.html You can see the large capacitor with 2 diodes at the bottom of the board. Look at the negative end of the second diode and you will see the clear LED just above and to the right next to an orange capacitor. Later I decided to unsolder the LED and mount it on the case which made more sense to me!! Thanks for watching, have a great day!
Thanks for this. I just ordered one of the copies. Now that I know the original is Banggood, I may order that one too. My only issue with the kit is be that 3 amp o/p is a little small for my application. I need about 4.5 amp max. Is there's a fix for that - to get more than 3 amps out of the circuit? - such as: using :
-- 2 output transistors in parallel.
-- Instead of 2 is there another fix to use a higher rated o/p transistor?
PS: You never said what the AC ouput of your trasnformer was. Presumably 24V AC?
Excellent - all round tutorial.
Hey thanks! I would only build this as an educational project not for "serious" use. It's an old linear design. If you want a supply for your DIY projects this is a better option : ruclips.net/video/ikTsE-UGN1s/видео.html Have a great day!
BTW my AC input is 220 volts! see the transformer listed in the video description....
@@1nformatica output not input. Is the output 24V AC; 10x stepdown?
@@mark4asp Sorry, my bad! Yes, 24V AC output.
For accurate V/A meter must to feed the meter itself from different small supply. One can change meter's little trimmers with multi turn trimmers. Then will be 10mV accurate. Drill the box! Cheers!
Good information, thanks! I did drill holes, you can just see them at the top behind the fan ruclips.net/video/t5N3iKWbSDM/видео.html
the fan will work quite happy on 12v too. 7 bucks on "bang good" for that money it looks a grand little kit,,, oh think I just realized that you didn't have a 24v fan.. but if you did 12v would run it too... question.. would you give this kit a thumbs up or down now that you have it a while now???
As an educational kit for learning electronics and assembly highly recommended. As a bench power supply it is OK but if you just want a supply there are better options.
Good afternoon, I bought a 24 + 24 3A transformer and when connecting and measuring with a multimeter I saw that the output voltage is 25v, I would like to know if I can connect this board with this Trafo?
Obrigado Michel! You do not say if you are measuring AC or DC values, I assume AC. It is not unusual for the "off load" voltage of a device to be a little higher than when in circuit so 24 - 25 volts AC is OK. Remember that the DC voltage produced when the AC is rectified and smoothed will be 1.414 times higher i.e. 24V AC = 34V DC so 25V AC = 35V DC. The input components, most importantly the capacitors are rated at 50 volts so I do not see any problem using that transformer. Tell me how it works out. RUclips no longer shows me if you are subscribed. Please consider subscribing if you have not done so already!
@@1nformatica Good afternoon, I am referring to 25V AC from the transformer output, as the kit board asks for a 24V ac input and my transformer is outputting 25.5V AC, I was in doubt if I could use this transformer, thank you very much for your help, you do you know what the input tolerance of this board is?
I'm already written on your channel.
When I finish setting up I say how it works, I'm using google translator disregard any writing errors.
@@michelluizvalente7024 Looking at the circuit diagram I would guess that it could tolerate an input of up to 30 V AC. 25.5 V AC should be no problem. Do not forget to put an insulating washer on the output transistor. Remember that this is an analogue power supply and not very efficient meaning it will get hot! Do not run it at high (+3 Amps) for long periods! Good luck with your project.
@@1nformatica Thank you very much for the information, for the output transistor I will use a heatsink with a cooler, this power supply that I will build and more for testing, if it is really good I will build a more powerful one, and again thank you very much for your help.
that current limiter transistor may melt the fan and the cabby if not careful i think.
Hi, the repurposed CPU fan does a good job of cooling things. The supply would have to be seriously overloaded for the transistor to get that hot!
Thank you for the Video very good you are taking me back with your description I have the same tap wrench but mine is English and the circuit is a copy from electronics website so all copied from England when we made everything those where the days, Glad you did not destroy your power supply. I am contacting you in the hope you would know the board dimensions as I have ordered one from China
Hi Bob, Yes happy days. I had the privilege to work for a while in a truly old fashioned Company. They had everything under one roof. Design, Model Shop, Mechanical Fabrication, Electrical & Electronic design and assembly. Goods inwards inspection and of course "Norman" the storeman who you had to keep on the right side of if you wanted anything quick! The PCB is approx 80mm Square. The box I used was 180x110x90 RS part number 220-440 enjoy! Hope you've subscribed and check out my Oscilloscope build ruclips.net/video/zNTXAwxTG0w/видео.html
Thank you for your help much appreciated I have subscribed to your channel as it was very interesting.
Cool! Let me know if you have any other questions.
Hello everyone: This circuit is quite good but the power transformer should not exceed 20V. The DC voltage in the supply (+ Vdc, -Vdc) in the operational ones when setting the 24V voltage exceeds the maximum values for which the manufacturer designed it. The maximum data sheet voltage says + Vcc - (- Vcc) = 36V, recommended 30V. It may work well for a while and then the operational ones will burn.
Do you have any diagram that you can pass me, I don't know how to connect the fan and the voltmeter, please help
The circuit diagram is in the instructions you can download here : img.banggood.com/file/products/201505080459530-30Vinstall.pdf The fan has it's own regulator 7824 for a 24 volt fan. You can change this for a 7812 regulator for 12 volt fan if you want. A voltmeter is simply wired across the output terminals. Thanks for watching, have a great day!
Thank you for your clear and informative video. Just the right balance between the construction process itself and the technical background, and good to hear that you were taught how to solder properly as well!
I have just completed a Banggood kit and have a problem that the current limit LED is illuminated even when voltage and current controls are fully wound anti-clockwise [to zero]. I checked individual component values as I assembled the kit and tested each semiconductor and Op-Amp as well. I am hesitant to leave the PSU powered up for too long in case a fault causes a burn-up so I have not got as far as using the trim pot to zero the voltage adjustment or current control. Do you have a note of the stand-by or quiescent current consumption of the PSU off -load? If I could be sure that I am in the right zone with that I could do some other voltage checks to see if I can locate the problem. I don't have a proper AC ammeter, but monitoring the AC voltage drop across a 100 ohm resistor suggests a stand-by current of about 50mA at present. [I have not yet fitted the fan and its associated regulator]. I would be grateful for any advice.
Thanks for commenting. Double check the power transistor is isolated from the heatsink ruclips.net/video/t5N3iKWbSDM/видео.html
I didn't take any quiescent current measurement I'm afraid. Also check for any solder bridges or dry joints. If the problem still persists then you'll need to start removing some components working back from the output stage until the short goes away. Good luck!
Great informative video. Electronics is my hobby but I am still a nubby. I purchased one of these kits but ran in to a couple of problems. The regulator supplied was a 7815 which I did not realize at the time was only for the fan so could have used a 7812. I carefully checked all components before assembly but missed one crucial one which happened to be the 0.47 ohm 5 watt resistor. The supplied resistor was a 47 ohm and without realizing it I installed it. On turn on the output trans and resistor became extremely hot so shut it down and that's when I found the wrong resistor. On replacing the resistor I turned the PSU back on and the 0.22uf MLCC capacitor exploded. I am now waiting on a delivery of replacements but do you think I may have shot any of the other components. I also want to change the 24 volt supply to DC and intend removing the IN5408's and wire the DC input direct to the 3300uf 50 volt cap. Will this work without changing anything else? Your assistance will be appreciated
Thanks for the comment. Seems like you had some bad luck there, I am surprised the resistor caused such a problem. It is impossible to say if other damage was done, you will have to try it and see! Maybe put a simple current limiter i.e. lightbulb in circuit : www.instructables.com/Light-Bulb-Current-Limiter/ Putting DC into the unit is OK, just remember you will need 24 * 1.414 = 34 volts DC for full output. Although this is an interesting project to build it is not a very efficient design being analogue. I will be making a video on a very versatile and inexpensive Switch Mode PSU for hobby use soon. RUclips no longer shows me if you are subscribed. Please consider subscribing if you have not done so already!
@@1nformatica Thanks for the quick reply. I have noticed that there are two versions of this PSU. The layout on the second from Banggood is much better but the circuit appears to be the same. The assembly and testing instructions are actually for the second one not the one you and I have assembled. Thanks for the heads up on the power requirements for using DC instead of AC.
Hi sir, nice work. Can you post a drawing scheme how do you connect all that connectora and Amp meter? Thanks
The connection diagram is here img.banggood.com/file/products/201505080459530-30Vinstall.pdf
Connection for the Amp / volt meter here www.banggood.com/Dual-Red-Blue-LED-Digital-Voltmeter-Ammeter-Panel-Volt-Gauge-Meter-p-918687.html?akmClientCountry=ES&p=NL2203782949201409M4&cur_warehouse=CN#customerQA
Hi does the kit have the schematic diagram?
www.paulvdiyblogs.net/2015/05/tuning-030v-dc-with-03a-psu-diy-kit.html
The schematic is at the end of the documentation which you can download from the product page : bit.ly/PSU_kit
Sir what be the voltage at pin 7 and 4 of op ic 1 2 and ti081
I am returning again after 3 years since building the Pcb only to complete it with a new transformer and an enclosure . One question please how to get a specific constant current for example I need to charge 18650 battery with as little as 150 mA at 4.2 volt , setting the voltage is easy but how to set the maximum current ? Thanks again
This is a very basic supply and you would have to calibrate the current setting yourself. To do this place your ammeter across the terminals and set the dial to the desired current value. Then mark the dial at that point. This will not be very accurate or repeatable due to the analogue potentiometer. I would not use this supply to charge cells / batteries especially Lithium Ion as overcharging may lead to explosion and fire!! LiPO cells should never be charged unattended. A much better supply for your needs is this one : ruclips.net/video/ikTsE-UGN1s/видео.html
Hi, I built the same kit a short while ago and used the same system for powering the fan and the display.
Everything worked until, unfortunately I made a short circuit with the output cables, now the voltage regulation no longer works, it always remains at maximum.
Short circuit protection was indicated in the description but this is probably not the case.
Now I have to go find what may have broken.
Some idea?
Did you set the current limit as here : ruclips.net/video/t5N3iKWbSDM/видео.html First port of call for you would be to check the output transistor, it is probably short circuit. Good luck! Thanks for watching, have a great day!
Thanks, I'll start checking from there.@@1nformatica
You could put two fans in series, one for the trans the other for case ventilation
Great idea! Thanks for the tip.
Very nice and informative video. Many thanks.
I am considering buying this DIY kit myself. But meanwhile, I have seen at least two videos with some discussion about heat development in the power transistor. So I am getting a bit reluctant.
Could you kindly help me with these three questions as follows:
1. Does the kit come with a legible circuit diagram?
2. In your video, if I read that correctly, I saw the secondary side power rating of the transformer you are using as 37.5VA @24V. Is that really 37.5VA or actually 375VA?
If it is 37.5VA, how can it deliver 30V @3A? Probably I read something wrong. Could you clarify this, please?
3. In your video, you are using a buck converter to generate 12V for the fan and the VA meter. Could you please give the part number and/or vendor of the buck converter, please?
Thanks a lot for your help in advance.
Hi If you follow the link in the description to the kit you can download the manual including circuit diagram. The transformer is this one : uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/ There are 2 windings making 75 VA @ 24 volts ac. so 24 * 1.414 gives 34 volts DC max is about 2.2 Amps. The buck converter is similar to this : bit.ly/DCDCBuck
Please consider subscribing if you have not done so already!
@@1nformatica Many thanks. Already subscribed.
Thank you for a very clear and concise video, and I especially appreciate your excellent diction. I have built the kit using a few mods I found and all was well until I started to connect an 8.5 amp Variac. Since I already had the Variac I was happy to not have to buy a 24 volt transformer. I am very much a novice whose only experience was limited to a general class ham license back in the early 60s!! As a result, I am totally confused on how to connect the 2 leads from the Variac to the 3 connections for 24 vac shown on the board! If you have the time, could you or anyone explain to this simpleton how to accomplish this---assuming it can be done? Does it have to do with earth ground, and if so, which lead as no polarity is shown? It has me frustrated, embarrassed and humiliated! Thanks so much for any help
Only the outside 2 connections are used and you can see the connection to my transformer here: ruclips.net/video/t5N3iKWbSDM/видео.html
As it is AC there is no polarity just connected the variac to those connections. Make sure before connecting the variac is set correctly!
@@1nformatica You have made my day! Thanks so very, very much for making clear a solution to a simple problem my lack of knowledge had blown way out of proportion!
@@denzilcypret742 No worries, feel free to ask more questions if you need and please consider subscribing!
awsome vid bought the kit myself can i be so bold as to suggest replacing the stock 10K pots with10 turn pots it will improve the precision of the device
Hi Federico, thanks for the comment. Yes, very good idea with a multiturn pot it would be easier to set the voltage accurately. Check out my other kit builds for an Oscilloscope : ruclips.net/video/zNTXAwxTG0w/видео.html and Geiger counter : ruclips.net/video/4Tqo3B98ZgM/видео.html
He already mentioned this in the video...
Hi ! can i use 12 5amp dc power supply ??
No. The project requires a 24 volt AC transformer. Please consider subscribing if you have not done so already!
@@1nformatica You can use a 24-30V DC as well, just don't solder in the bridge diodes and hook it straight to the filtering cap
@@ivolol Good idea, thanks for sharing. Please consider subscribing if you have not done so already!
Hi, Can You send me link for your part "D-SUN" connection LED Digital Voltmeter Ammeter Panel Meter and FAN? I would like buy this part. Thank you.
Here you are :
Mini DC-DC Converter Step Down Module bit.ly/DC-DC_StepDown
LED Digital Voltmeter Ammeter Panel Meter bit.ly/VAPanelMeter
Hiland Heat-Sink +Cooling-Fan bit.ly/Fan_Heatsink
Please consider subscribing if you have not done so already!
Thank you for such an informative and well-done video. I have just finished this kit and it immediately blew my 3A fuse. I am currently following your suggestions elsewhere in the video to find the fault(s). But I do have a question I believe you can help with. Do I need to have an insulator between the 7824 regulator and the D1047 transistor and their heat sinks? I did use a conductive grease. I have read that sometimes an insulator is required but of course that would depend on the circuit. Any help is appreciated!
Hi, thanks for the comment. The transistor does need to be insulated from the heat sink. The regulator needs no insulator as the centre tab is ground. Hope that solves the problem!
@@1nformatica Man, that was quick and straightforward! I didn't use an insulator as one wasn't called for and it may be the culprit! I owe you!
From the instructions "Please make sure that you
have installed cooling fin of considerable size on Q4
(D1047) before starting the power, _ and the cooling fin
should be insulated from the circuit _."
@@1nformatica OOPS! Thanks for the gentle reminder. I watched the video several times and completely skimmed over it! When will I ever learn.........
RTFM!! Good luck with your projects.
I have built a number of these kits but now I'm trying to wire an ebay special amp/volt meter but I dont know where to wire the large red wire from the current . I'm using a 24 vac transform step down from 110ac can you help with possibly a schematic showing the power supply as I'm not very fluent with wiring schematics. I am teaching myself these thing via youtube lol p.s my problem is where i understand that these amp/volt meters have to be wired up funny if trying to measure volts and current from the same source where I loose track is that my source of power is 24vac where do I hook the large black wire from the amp meter if I'm hooking the power (red) and sense (yellow) to the positive of the load and the positive of the amp meter (large red) to the neg of the load leaving the ground of volt meter (smaller black) un soldered, when in this scenario the larger black amp wire is to be soldered to the positive of the current source. Where this power supply is sourced by ac I'm stumped and therefore have no reading of the current in which can be adjusted with this kit.. Can you help? If so please email me @ Stangreer8792@gmail.com I can then email you pictures of my components and supply as a whole thank you
Hi Stan, email sent.
on my power supply The rheostat does not change the voltage value, and the maximum voltage I can reach is 25V (THE 82 OHM AND 220 OHM RESISTORS ARE HEATING) can someone help me?
Check that you have the main power transistor insulate from the heatsink. Otherwise double check all you wiring and solder joints. Good Luck. Feliz Natal!
I brought 30V 3A DC Regulated Power Supply Kit and LED Digital Voltmeter Ammeter Panel Meter, all components soldered and it worked well but when I connected LED Digital Voltmeter Ammeter Panel Meter I probably shorted out now I get input and out 30V with no regulation on pot voltage, where to locate the fault have I blown a IC or zener diode?
Hi Joe, I would check the output transistor for short circuit first using a multimeter or transistor tester if you have one. The circuit diagram is at the end of the assembly instructions you can download from the product link : bit.ly/PSU_kit
If you don't find the problem I would start troubleshooting from the input ac forwards and test each stage. Good Luck!
Problem rectified..you were spot on, Found fault with transistor 2SD882 which I replaced with BD139 now it works good. Thank you very much for your prompt guidance.
Good news Joe!! Glad you got it fixed. Take care you don't use it at high currents, the BD139 is only a 1.5 Amp transistor with 3 Amp peak rating. A little close to the edge!
Thanks...2SD822 was not available so I used DB139, I used my multi-meter to check peak amps output at 30 volts I only get 2.64 amps so it should be fine , But I will keep in mind not to exceed 1.5 amp..This was my first major project completed with not much basic skills in electronics apart from soldering..smile ..and at 62yrs. I'm thrilled to solve a problem with your help and guidance...Thanks once again take care God bless.
Thank you Joe. I'm only 2 years younger than you and just starting to learn CNC! Check out my playlist for Electronics projects aimed at beginners: ruclips.net/p/PLxtbRS-naT6_7U7svrrTfRsy9Prhpx3iC
Feel free to ask any questions or suggest projects you would like to see me build. Cheers!
To what depth can you dive with this device? 🐟
I would strongly advise against operating any mains voltage supplied equipment under water! Thanks for watching, have a great day!
Got mine all soldered. The voltage works fine but when I turn it on the current is saturated to the max. I v checked for short circuit, can't find any. There is no load but the current limiter is on. Any idea?
Did you insulate the power transistor? ruclips.net/video/t5N3iKWbSDM/видео.html
@@1nformatica I havent mounted it on a heat sink yet, as it is the first test after I finished the soldering
@@guillaumelombard7210 Do you have a panel meter for current wired in? I have seen some panel meters with different coloured wires and it is easy to get confused.
@@1nformatica it s bare, I removed all external component that could be causing trouble. I m thinking of swapping the power transistor as I cant think of anything else that could draw that much power (other than a short circuit)
@@guillaumelombard7210 Have you checked the transistor with your meter?
Hi, Great video. Can you offer any advice please on replacing the PCB mounted LED with a panel mounted version i.e. voltage, current, please.
Hello, sorry I do not understand. In the video I use this LED Digital Voltmeter Ammeter Panel Meter bit.ly/VAPanelMeter
@@1nformatica Hi, Sorry for the confusion. On the PCB there is an LED installed that illuminates when the circuit is 'in constant current limit mode'. Towards the end of the video it appears that you have removed the LED mounted to the PCB and replaced this with a panel mount LED, so that this function is shown on the outside of the enclosure (to the left of the digital VA meter display).
You can put 3mm or 5mm LEDs in these holders : 10PCS 3MM Round Chrome Metal Plastic LED Bezel Holder bit.ly/LED_PanelMnt
@@1nformatica Thank you.
You're welcome!
Hi! Just made one of these myself. Curious, do you know when the fan is supposed to kick in? Is it at a certain temp? Haven't seen mine come on yet!
The fan is fed directly from a 24 volt regulator, it should be on all the time. Check you have + 24 volts DC on the pcb connector. Please consider subscribing if you have not done so already!
@@1nformatica I realise now mine is a slightly different design and kicks in with a thermistor! Thanks
@@1nformatica Also I subbed! Just thought I'd message you from my channel account if you fancy checking that out too
@@jonathanreader6503 A better design then, fan noise when it's not needed is just annoying!
@@jcracoustics Thanks, I liked the video on starting a 3D print business, great tips and advice!
Hi, My output voltage is only 26v, any reasons, I should be getting 32volts correct
Hi, much depends on the transformer you have. Check what the voltage is on the circuit board after the bridge rectifier, that will be your max output voltage.
@@1nformatica I am getting 33v after bridge rectification
@@patrickvaz2002 Did you do the calibration? ruclips.net/video/t5N3iKWbSDM/видео.html
@@1nformatica hi, Thankyou so much, I need to calibrate the same👍👍
it has some short circuit protection ? or it works to find shorts?
Yes, it has a current limit you can set. Do not leave it connected to a short circuit for long as the supply will overheat, it will need a good fan and ventilation. Please consider subscribing if you have not done so already!
have you tried with a load that absorbs 3A? Is the heatsink of the power transistor in the video sufficient when we have low voltages and high current?
I do not use it for high currents. There is a cooling fan and I cut holes in the box to help with cooling but it will still get warm as the design is very basic. At 3 Amps I would not use it for long periods.
Hi. Realy nice video. I soldered exatly same kit. But got a problem is no reaction to pot regulation. And is noting on output.
And is no -5.1v betveen ic pin4 and r3. Electronic is like my hobby. But i not strong enought to sort that. I understanding schematics but canot read or trace how the components effects etch other. Hope you can help.
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
@@1nformatica thanks for advice. Wuold do. I found some parts its not soldered trough the board. Some clear of soldering in the opposite of board. May that be isue to. Wuold add some flux and resolder every joint.
A good start. Let me know when you fix it!
hey i have a Problem, i have the same board and used an led plug (24v) for the input but it doesnt work. when i measure the input voltage it was 31v (idk why, also doesnt change when potentiometers are turned) und the output voltage was -0,59v. Is my board fried? While the ac plug was connected nothing really got hot so i have the hope that nothing is broken. the led was also always on but idk why.
Im a electronics noob and wanted to do some projects with it so i hope you can help, thanks.
I do not understand what you are using to power the board. You should use a transformer like this one : uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/
@@1nformatica hey im using smth like this www.ebay.de/itm/Netzteil-24V-AC-Wechselstrom-IP44-f-r-Au-en-6W-50Hz-Konstsmide-Trafo-Driver/254743551310?mkevt=1&mkcid=1&mkrid=707-53477-19255-0&campid=5338364442&customid=254743551310_159912&toolid=11000&pageci=50e66d82-01e6-4d61-b2c0-2ceac79db5a1 because i didn't had a transformator that you send.
@@MrAnimeAmv1 That device cannot supply sufficient power. You see it is 6VA or 6 Watts. Power = Volts * Amps so 6W at 24 volts is only 250 mA. You need to find a transformer with at least 75 Watts as the one I showed you.
I'm building one of these PSU kits now, I'm going to replace the 24v regulator with an LM7812 regulator. I've had the idea that if I use 2 secondary transformer I can have a switch to select where I tap it from. So if i'm only using below 15v say, I can just select 1 secondary coil reducing the input to the kit to a voltage that the transistor can cope with., (I'll need 15v min for the 7812 to operate ). Ive seen a video where he only had a 12v supply at the time & it still worked. What do you think?.
The 24 volt regulator is only there to power the fan. I am sure if you reduce the AC input voltage it will work but obviously be limited in it's output voltage. I do not see a reason to do that. Better to find a 24 volt AC transformer.
Sorry, I think you misunderstood me. The LM7812 input voltage max is 35v, if the voltage at the input to the 24v regulator is less than this you can replace the 24v regulator with the LM7812 regulator. The idea of switching the tapping point on the secondry coil is so if you are only wanting a lower voltage say 15v dc, then you can switch to tapping just one half of a dual secondary, the power transister wouldn't have to work so hard. I believe that some manufacturers of PSU use this technique.
brilliant video dad very usefull
Where i am wrong with building this kit.. I have not stable voltage at the output.
What can it be?!
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
Great video! Very curious to see how you tapped into the 24V line on the board. One question form an amateur: in this configuration do you need the board's 24V voltage regulator at all? Can't you just leave it out, solder wires onto the holes where it was supposed to go, and then take those wires directly to the small step-down converter that you use?
Hi, I just tapped onto the +24 volt connection that is for the 24 volt fan. You're right the regulator is not really needed. I think I assembled the kit before I realised I did not have a 24 volt fan! Doh!!
Hello I would like to know how it is possible if it is possible to use this power supply only for 15 volts and only 2 Amps max or 1A it's for the third way of my double channel in DIY Thanks a lot
Hi Karen, it is fully adjustable from 0 to 30 volts so 15 volts not a problem. You can also set the current limit as you need.
I can use a 100VA transformer, right? The PSU won't draw more than it can chew (i.e. over 3A 24VAC), will it?
Sure, no problem. The transformer I used is only 75VA uk.rs-online.com/web/p/chassis-mounting-transformers/0504060/
I don't tend to use the supply at high currents.
@@1nformatica Thank you. I don't think it would handle long term high current draw very well anyway, not without some heavy duty active cooling and a massive heatsink. And thanks for the video!
Hi, what's the purpose of that little blue trimmer? Does this kit include manual instructions including how to adjust that little trimmer?
The trimmer is to adjust the output voltage zero point as I show in the video ruclips.net/video/t5N3iKWbSDM/видео.html
You can download the assembly and calibration instructions from the product web page bit.ly/PSU_kit
He literally shows exactly how to use the trimmer in the video and explains what it’s for. WTF? Did you even watch it?
Good day sir
After assembly the circuit out not getting stable initially goes to max voltage and then back to 1v
Checked all components
One ic u2 getting hot when increasing the pot but in output no voltage
I used 24v ac input
Pls help me
First you should check that all the components are in the correct position. It is very easy to put the resistors in wrong as the colour codes can be difficult to read. You should check each against the component listing using a multimeter. Examine and compare your board to the clear photos in the assembly guide, look especially at the diodes and transistors are the right way around. Good luck!
You may have blown the TL081. Max voltage for those is 36V (+ /- 18V.). This is a really poor Opamp for this.
Sir i am trying out this board and facing problem. When i power it on, the 24v output is on and fan is running but output voltage remains 0.05 to 0.1 volt when rotating the 10k pot.Also tried Trimmer in pcb calibration but not worked though. I am using a 24-0-24 v ,2 Amp transformer except 3Amp(As its not available here). Sir please help to sort it out.
Start by checking every component is placed correctly. The resistor colour codes can be difficult to read so check them with a multimeter. Check diodes are correctly polarised and IC's the correct pin 1. Check the soldering for any missed / bad joints. If you find no error then the circuit diagram is in the instruction manual and you will need to follow it to diagnose the problem. Good luck!
bangood has given the pdf manual.But where is the diagnosis manual?please help me out.😖
The pdf manual is the only one I think. It has the adjustment procedure and the circuit diagram on the last page. 99% of problems are from incorrect assembly, as I said before double check everything. The circuit is relatively simple and if you do not understand how it works then now is time to learn! If there is no one near you that can help you (local college / university, repair shop) then Google is your friend to find the data on each component. Good luck!
thanks for your concern sir.I am double checking it.. 😃
Thanks for sharing
Thanks! More kit builds here: ruclips.net/p/PLxtbRS-naT6_7U7svrrTfRsy9Prhpx3iC
can you make it for 5 amp
Not easily. You could change the output transistor for a higher amp and use a bigger transformer. But is is a linear design and not very efficient. A better solution for a bench power supply is this module ruclips.net/video/zfkcfn-hCmg/видео.html matched with an inexpensive switch mode PSU would be good.
the heatsink is to small if you use more than 1 amp and the cooler need air make Some holes in there for Circulation. best regards Daniel
Hi Daniel, thanks for the comment. I did put holes in the top of the case for air flow and made sure the fan was set to blow air out of the case. I should have made that clear in the video so thanks for pointing that out. Best regards.
👍
You're welcome! Have a great day!!
I have built the same kit. I enjoyed it very much.
thank you for the video!
I added a dual volt and amp meter, but on my meter the ground to the volt and amp meter and common. Therefore I had a problem powering it from the board like you did.
Are yours the same or are the negative to the amp meter and volt meter separate?
kind regards
Hi Stephen, It's a nice kit. The Volt / Amp meter ground is common on the meter I used as well. You can see the wiring on this link: forum.banggood.com/forum-topic-47750.html
Thank you very much for your response.
I enjoyed the video!
I'll recheck the influence of the meter on my circuit.
I know that the 7824 (voltage regulator) provides no isolation. I presume neither does the buck converter (so the neg on the output of the buck converted it common to the neg output terminal of the kit). What do you think?
Kind regards
Stephan
ps: At first I was wondering why you opted for the buck converter and didn't change the 7824 to a 7812, but your answer to +Laziter73 made a lot of sense. The buck converter is a lot more efficient that the linear converters. Did you power the buck converter from the rectified point or via the 7824?
Hi Stephen, Yes the buck converter ground is common to the supply. It was connected to the 7824 output. Check out my favorite kit build so far ... ruclips.net/video/zNTXAwxTG0w/видео.html
sir i bought this kit and the same display you are using and when i connected the display with it i lost the current control feature but when display is not connected i can actually control the current with voltage . sir when i connected this display with this board ten even if current pot is at zero and i increase voltage current keeps increasing even the the current pot is at zero so i tried to measure in different ways and at the end i connected +ve of ampere meter to +ve of output of board and -ve to -ve output and connected load with and it get short Circuited and i killed the board for now, sir i ordered a new one it will arrive in a week , please tell me what i am doing wrong what i need to do?? please help me out
The wiring of the meter is confusing and the colours of the wires can change depending where you bought the meter from. My example has black, green and red wires ( as well as the red and black thin wires for power to display). The main "thick" wires are connected as follows. Red goes to the positive output of the power supply. Green goes to your negative output socket NOT the power supply output. Black goes to the negative power supply output. There is a separate red wire from the positive power supply output to the front panel positive socket. Also see this information : forum.banggood.com/forum-topic-47750.html Good luck!
ok sir i ordered a kit i'll do it and then i'll let you know about it
Take care and you will be OK.
1nformatica ok sir thank you
sir yesterday i bought a new one and the problem is same when i remove current shunt of display and i connect a motor at the output of power supply everything works great and i can limit the current with current potentiometer but when i use current shunt of display to read the current it reads current well but it creates a problem and that is if even my current potentiometer is at zero still if i increase only voltage then current also rises even current potentiometer is at zero i don't know what is wrong with it sir please help , i bought a new display and a new power supply board because i thought previous one was not working fine, so please help me out.thanks in advance
Thanks for sharing . Liked and subscribed .
Thanks! You may like this series of mine......... ruclips.net/p/PLxtbRS-naT6_7U7svrrTfRsy9Prhpx3iC
Why not just replace the LM7824 with an LM7812? Instead of worrying about an external regulator
Good idea, wish I'd thought of that!
Very good! Helped me out, a beginner, a lot! THX! :*)
Hey thanks! I have a playlist of videos you may also find useful ruclips.net/p/PLxtbRS-naT6_7U7svrrTfRsy9Prhpx3iC Hope you will subscribe for more!
1nformatica Ah-ha! More goodies! Thx! :*)
You're welcome! What projects are you working on? What would you like to see me build?
1nformatica Wow! You're certainly 'one of the good guys' of RUclips! ÷*)
Being an absolute beginner, my _current_ projects are limited to R/C aircraft (LEDs/Autonomous flight/PWM and serial control/etc.) related stuff. And, I'm new to a lot of the lower-level workings of those, too. LOL! A real beginner I am.
But, hey! I'm willing and determined to learn as much as I possibly can. ÷*)
Hmm... What would I like to see you build next? Oh my! How utterly thoughtful of you. _Huge THX!_
May I take a rain-check (so to speak) on that subject, just for a short time? I'll be giving it some serious thought, I promise.
Albeit, when my kit arrives, any day now, I guarantee I'll have a question or two. Nothing to badger and burden you with. I can figure out most things on my own.
By the way, in the unlikely event RUclips hasn't/doesn't notified/notify you, I've subscribed. Oh, yippee! Right? ÷*)
Aw shucks! Thanks for subscribing and feel free to ask any questions. Remember there are no stupid questions only stupid answers! I have the autonomous flight bug now having bought a Hubsan H501S ruclips.net/user/edit?o=U&video_id=n2W37DzzmYQ
I have an Ardupilot APM 2.8 Flight Control Board here waiting my attention.
What's that big heavy thing ? Oh yea a Transformer. I heard of those. LOL
This is a real man's power supply. None of your nancy switch mode here!!
Thank you for helping me in many things i sub
Thanks to you too! If there is some topic you would like me to make a video on please let me know.
Dear Mr/ @@1nformatica I will definitely return back to you..after receiving my item
I apologize for many of my questions
,when we enjoy loving those who helped us.it's a virtue !~(^_^)~ Thank you very much
man kann es nicht mit 3A belasten, 1,5A mehr sollte es nicht sein auf Dauer
Agreed, this linear design is not the most efficient and will get hot at higher currents if not properly cooled. However, as an educational kit it suits its purpose well. Haben Sie einen guten Tag!
Vide: br.pinterest.com/tiredmg/fonte-hiland-de-030vdc-x-2ma3a/
Oh dear, believing the rating label on a Chinese capacitor, you must be new here...