Hi, I think the difference between no load voltage and load voltage can be that high, because you measure voltage without drop over the cables to your dummy load. I can't see any extra cables going from output to a voltmeter. So without considering that you shouldn't say the load regulation is unacceptable, as the circuit has external output resistance applied.
I was watching this and thought exactly the same thing. Needs to do a 4 wire measurement I think or increase the voltage to get the required voltage seen at the load.
@@405line If you watch his other videos, he uses the exact same setup for different modules and some of them fare much better from voltage drop so I don't think it's his setup's fault.
Hi RoboJax, here a contribution from me that solved my question below. I have used it on a solar panel and yes it does function at least till 42.5Volts. The control chip is a LM5116 which handles 100V. Careful, the capacitor on the module can't. Check the chip there is a LM25116 which handles only max 45V and is similar to the LM5116. See below a picture from the back of the PCB with most components identified. If anyone can tell me what the current limiting circuit looks like I'll be happy to know. I tested it on a real PV panel of 42.5V and 14.5V out at 10 AMPs It does get hot, extra cooling is needed. The chip runs on 300Khz if I remember right. This means that the 3 strains transformer with 0.7mm wire can be optimized by using one with a smaller diameter but more strains due to skin effect in the copper strains. Putting the MOSFETS in parallel with the same type might help too. The 3.5 Amp gate drive of the LM5116 should handle that. Changing it with a lower RDSon is a better idea. A IRFB3077 75Vds 2.8mOhm RDSon for sale at AliExpress lowers the Temperature www.holamex.nl/files/img/SMPS%2020A%20parts%20identified.jpg
The difference in the output when the load are are attached / not attached is because of the resistance of the wires. In this particular setup the wire resistance seems to be around 41 mOhm. If your DC load is capable of doing 4-point measumrents then you can just hookup the voltage probes directly to the DC/DC converter output and then get the true output voltage.
Hi, very nice review. One tip, you should put one voltmeter directly on output of converter/pcb because voltage on on your Rigol load is slightly lower due to voltage drop in cables. Buck converter tries to maintain voltage but cant "see" value on the other side of cable.
Hi, thanks. I've fixed that in the later videos. The electronic load as voltages sensor wires which I can connected to the output for just measuring the voltage to show correct reading.
Thank you for taking the time to make this helpful video. I bought this unit form Temu at a very cheap price for the quality of the unit. It should useful many hobby projects.
Use 4 wire measurement system to eliminate wire voltage drop. The module regulates the voltage based upon what voltage is present on the module terminals but there is a voltage drop in wires which carry current from the module to the load. The electronic load measures voltage on its own terminals and not on the module terminals so it is no surprise that you will not get the full output voltage set on the module.
2:54 you was asking about the name of Chip . It is ( LM25116MHX ) from Texas instruments . And it's 40v max input and it's better not to pass 35v input . And have dual mosfet control for the VC and CC. I get the name after I pop up my'n during sudden input voltage change from 32v to 50v by mistake in my power supply . Everything was fine in test but the DC converter not step down any more and I suspect that this ic was not working and I was not able to find any data sheet about it but I email the company store that in AliExpress from China and they give me the number and I buy 15unit for 5$
Another Great and full detailed video by Robojax. I'm planing to make an mppt solar charge controller and this video helps me a lot. Thanks again Robojax
It seems that your power supply can not handle the current demanded by the Buck and has to steel it from the voltage, that's why you are seeing voltage drops in higher voltage tests.... Suggest to use a higher current voltage supply so it would be able to saturate the Buck properly, otherwise all your tests are null and void or you might say a 20% accuracy level!.... Yes, you might have a lab power supply but they are useless in here, you need an IGBT that's able to produce huge amounts of current to saturate any other Buck converter.....
Hello rj, can you answer my 2 questions. 1. Is a diode needed to prevent back flow for charging a battery or battery can be connected directly to load terminals ? 2. Is there a way to enhance their voc as I see all models come with mostly 40v. Can it be upgraded by swapping out a few components such as input capacitors or so ?
Excuse me. In which case this converter may burns a potentiometer. I replaced the embedded potentiometer and I tried another one of 10k and 100k. Same result. Burned. I powered a fan 12V 0.41 A. Thank you.
The test is more correct at standard voltages 12 24 36 48 volt :). For example 36 to 12v 36 to 24volt test :). Thanks a lot of nice reviews you have. Hope you have a cool 36-48 volt power supply :D
🙏🙏 From Sri Lanka. Very informative, thank you very much. It is admirable that how you find time to answer all these questions. Comments from readers also helped me a lot.
You are welcome. The best thank you for me is to subscribe to my channel. Your subscription is stamp of approval and my videos will be suggested to more people and this will help me. I appreciate it. thanks❤️
Very useful demonstration. Just wondering, how hot is too hot for the heatsink on this kind of device? If I can't keep my finger on it, is that dangerously overheated? Or is that normal?
Yes if it burns your finger, that is above 80C so inside chip junction is 50 or 40C more like 120C and that is right at the edge. So check datasheet and see what is junction temperature.
Thanks for your time in making your review. I wanted to ask a question. If the input on the converter changes does it also mirror the same changes in the output? Or does the output stay the same regardless of any fluctuations of Voltage/Current from the input? Thank you & I look forward to your reply
What I want to see, is how this module can regulate a constant current under different input voltages, I was expecting that you set a specific output voltage and change the input to see how it constant ut can regulate the voltage under such circumstances
you test load rig does not have a 00 gauge wire, the 1 volt drop is caused by your wire in the output, unless you place another voltmeter right on the output, 15A will have a large drop on the wire
00 Gauge wire is rated for 100A to 200A. We need maximum of 20A. But I agree, eliminating voltage drop should have been taken into consideration. Thanks for tip though
@@robojax you could just use a separate voltage tester right on the output port separate from the load wire and there upi can decide on the 0.5vo;t drop in regulation. yes is overrated but wires have resistances, the voltage drop of 0.5volt for a regulator for it not to pass is very easy, since even a 14 a 20amp rated wire still has a resistance proportional to length and these are working with low voltage. proper instrumentation test for out voltage regulation will be a separate voltmeter exactly on the output. you have a good load test equipment, ithe voltage measured is on the load itself, measured with the wire and your are testing large currents. maybe a separate tester on the output to see regulations. thanks for the reviews anyway
Can I measure output current by shorting the output or do I need to have a load? I do not have a dummy load and I am planning on using this for some DIY projects, as power supply, and maybe as a battery charger. Nice video by the way but it would have been better if it had CC testing. Thank you!
Normally this is how you set the current. You short circuit the output and set the current.. I have not done it on this module but it should work. You are right I should I have tested it with CC.
@@robojax I was just worried the chip may not support short circuit and end up frying the module. I'll try it when my module arrives. Thank you for the confirmation.
Best to first wind down the CC pot to zero before you short - then bring it up to the desired current. I use a few assorted sizes of car bulbs as Loads. Only a few dollars each.
Thanks for doing these tests, but some of us are okay with raising the input voltage to offset voltage droop. Unfortunately you didn't actually show how many amps this buck converter can handle on a long term basis. I am pretty sure it would melt down at 20 Amps, but it would have been nice to find out the limit...
I agree with you. The result I have presented based how hot under certain current it gets. If the temperature increased I have reduced the current. It is very hard to satisfy everyone with the result.
Thanks again for doing the reviews. They are very informative and you are the only one doing them well. But if you can determine how many amps and how many watts a supply can be used for without overheating, I think this would be very useful for many people. For many of us using high power supplies, the load is fairly constant, so voltage droop is annoying but not debilitating. Unfortunately, whereas it is unusual to find a product from Germany that doesn't meet its specs, and most products from the US or Japan or Korea meet their specs, in China, the specs are generally just a list of what the board manufacturer thinks a customer might want to see. So it is always a crap shoot to figure out whether it makes sense to buy a no-name Chinese product or pay three times as much for something with a better pedigree...
If I want to set it to output 5A max, can i directly hook a multimeter to the output terminals and adjust the current limiting potentiometer until the multimeter displays 5 Amps? Or will this damage the buck converter? Btw thank you for these reviews, I've learned a lot from your videos.
Hello sir i have a question .. what will happen if the output terminals shorted ? Does it have a short-circuit protection feature or will the module burn? Let's say input voltage is 35v 7amp dc . Thank you so much for the detailed video on this module. I love it
Looks like the main problem with these supplies is the voltage drop at output. With the current limit they are acceptable, at least someone will load it to the acceptable thermal limit, knowing that is only 8A or whatever. But the output drops so much in voltage that is nasty. What chip is the controller, LM25116? And for me, I would choose transistors with lower internal capacitances
yes you can. BUT and that is a very important but. you have to set both output exactly the same and both current setting exactly the same. then you can connect them in parallel. if you don't, then if there difference, the current will flow from one to the other one and that is dangerous.
@@robojax what if we connect a Blocking Diode on output of each of these in parallel to prevent current flowing from one buck into another in case of mismatch. Will that be safe.
Thanks for this review. The efficiency at 15:05 can't be correct with an input of 44.4W and an output of 17.7W. (17 / 44) * 100 = ~38%. Also efficiency is spelled wrong.
+1 -- Mr Kowalczyk. Also, I didn't see you confirming that the Current Limit function was not influencing the alleged 'poor regulation', at each new setting. There may be quite a bit of interaction between the two trimpots -- after all, the thing is very compact for these power levels.
when we talk about 20A or 20,000mA, 1% of this which is 200mA does not matter. Because most components have 5% to 10% error in them. That's why I did not measure it.
Hello friend, how are you? I ended up buying an equal one and when I connect a device to the power outlet the amperage does not go up being useless, but when I test it without connecting anything to the outlet the amperage works normally, you know what may be happening?
Hi maybe you can help. I want to use this module in a project but want to relocate the two CV and CC trim pots. I have un soldered them and planned to use some 28awg ribbon cable. Approx 150mm long so that I can mount the trim pots in an accessible place. Is this 28awg wire OK or should I use a thicker cable? I appreciate any advice you can give. Thanks and Happy New year!
Have seen some of your videos - they are nicely done and thoroughly put. I wish you good. Thanks for the videos. One question - how would you conclude the design comments on the unit? Is it rugged and looks long lasting for a continuous heavy duty usage in parallels??? Regards
Theoretically it is not a good idea to connect two of them in parallel as it is very hard to to set exact voltage on both and exact current on both. but you can connect if you can set both at the same value. I have given my opinion, watch the video fully. You haven't subscribed to my channel. I will reply to all Subscriber's 🔔 questions. So make sure to Subscribe.😊
I buy this model . Since they say it's the is a powerful buck converter 20amp . But as I see it's not 20amp . But I think if we change the coil and the capacitors in output you may get a better results . But I don't know how to calculate what coil need for 20A and what capacitors is exactly what need . Can you test by change the coil with bigger coil and less turn ?
You can do it but it would be very hard. You would have to draw the schematic, understand the design, then calculate the values. So it would be very hard.
No problem thx for your help. I ordered another module because I burned one MOSFET and I did realize that the ones soldered are FAKE, unbelievable!! That's why it can't even get close to 20 amps and working at that current for long time. Anyway I saw a video of a Russian guy that has replaced the MOSFET irfb3607 with irf1404 that he claims to be more powerful in terms of current (80A against 162A), but I don't have a proper knowledge to evaluate this option. If you can please let me know.
I want to control high torque servo like 35KG, i am planning to use this module for 4 servo powering. To get max torque i need 6volt 4 amps. Is it possible to get: --- input 12 volt 4200mah lipo -- want to get 6volt 18amp output??
Hello Sir... Can you help me?... I want to make Power Supply with this module but there is something wrong after I want to try operate. I change the potentio with bourn multi turn. The module die... How can I fix it. In the module there is no sign of burn part... Thank you before.
normally ground should be common on DC system. I don't have the device in hand as I don't know where I put it with thee volume of items I am getting to make video for.
I didn't understand why you did not crank it up on the output current load to the point of shutdown, like you did with others step down buck converters. That would have been very informative, I was interest in the max current this module could delivery before it quits, or starts screaming.
I did it. As soon the output voltage drops, that is IT it won't work. If I want 12V at 5A at output and it gives 11V it has failed. Doesn't matter if I increase the current to 6A. it is useless if you increase the current it will show (for example) 7A or 10A the voltage will drop more to 10V or 9V . so it doesn't matter.
@@robojax So, it seems this module is a far cry from the claimed 20 Amps / 300 Watts. Shame on the manufacturer for advertising it as able to handle much more than it really can. So far I have been unable to find a review of a Buck Step-Down DC-DC converter that really deliveries more than 5/6 Amps in 12 Volts, on a regular basis and without going too hot(energy lost to heat, instead of putting some extra Amps in the output and keeping the Volts steady).
Hello, I am glad you liked this. It will not work. you need total modification. The constant current section is checking for specific current and turning the voltage low when it detects certain value.
if it works or not, I don't know . to answer your question, I have to watch the video. So you watch and see which part is closer to your voltages and decide if it works or not.
I tried to connect 12-24 V DC- brushed motor to this DC-DC, as input I used 12 V battery, Voltage regulating is working normal, if you connect any voltage, as output You can become 1-2 volts less, as input. I could not become >11.2 V from 12 Volt input. Current was about 280 mA and current regulating works not or it need some A current for regulating, Adjustable resistor for current could not change the current 270-280 mA, and I am thinking, if I must send that back (defect) or it is normal...? Later I will try with some powerful motor. If it can give more current, as input, I don't know, you can try or wait answers , who did that already. I think, you can count like this, your output power will be about 5% less, as input power. In your case 20x12=240 -5%=228Watt,, 15Vx15A = 225 Watt, in theory it can that, in practice I don't know.
I have a question. What happens if the input voltage is more than the regulated voltage? For example say I'm trying to get 12 volts from a generator that fluctuates in rpms creating an input voltage range of 5v to 20v and I'm wanting to get 12v constantly.
If input voltage is above the voltage of Capacitors, they will explode. The chip will handle some excess of voltage. I have provided the datasheet. the fluctuation within the input range should not have affect as long as it is just a little above output voltage.
For this converter to work, input voltage must always be over the regulated voltage. On your case, you will be getting 5V-12V at the output. If you want to keep the voltage stable at 12V, you'll have to add a large enough capacitor at the input.
You need a "Buck / Boost" converter if the input voltage can drop below the required output voltage. This one is 'Buck' only - it can only reduce the voltage. 'Buck / Boost's are available on eBay for about the same price.
Hello sir thanks for this review, can i increase my output voltage up to 24vDC with this power module even if my input voltage source is just 12vDC? sorry about my bad english, thank you. edit: Would you recommend one that can achieve that?
Hello, this is "Step down" or "Buck converter" so it ALWAYS reduces. if you want to increase then you need "Boost Converter" See my videos on boost converter ua-cam.com/users/robojaxTVsearch?query=boost
Hi i know this is a very stupid question. I am now starting to learn about motherboard repair and in need for power supply that can supply high volt an variable ampere. My question is can if i set this to let say 20V, and i didnt touch the potentiometer at all, will it supply the needed ampere required from the load or it will stay stuck at a certain ampere and i will have ti match it with the load. Thanks!
Hi, no question is stupid question. For power remember P(input)=P(output)-15% meaning output will always be less due to losses. So you can calculate the power easily P=VxI where I is current in A unit. yes Const current means it will keep the current constant and not changed. but this is only possible if the input can supply the needed current. Remember the outpt P can't be higher the input P or Power.
Hi RoboJax thanks for the clear video. I have a question and I hope you can help me. I want to use this module on a 72Cell 300Watt solar panels with a Open voltage Vco of 43V. That just outside the absolute maximum ratings of the TL8711. This TL8711 seem to be, but is not fore sure , the 20Pin control chip at the back of the module. Your video is posted on UA-cam with a picture indicating that this module is tested for 6..60V input voltages. The content of you video only shows 30V and lower input voltages. Can you tell me if you really have tested this module successful at voltage till 60V?. Is the Vcc of the control chip directly coming from the input or is that coming from a regulator meaning the max input voltage is determent by this regulator and the max Vds of the FET's being used. Hope you can tell me that.
By the design, NO . To increase the current , both capacitors and inductor are the main components to change and increase the current. Then you will look at proper mosfet to handle that current
Nice video. got exactly the same thing given to me but is missing a componentand have not tested it yet. Would you be kind enough to measure or give me the value of C15 (filter cap on CV out potentiometer). Thanks in advance.
Hello, the voltage can be adjusted in my product, but current limitation cannot be made. What could be the reason, do you have any information? Thanks.
Hello, unless the potentiometer is broken or the module is bad there is not other information. I assume that you followed the video. Please subscribe. I appreciate it and helps my channel grow. Thank you
@@robojax Thanks, I inserted a different potentiometer thinking it might be broken but the result did not change. the voltage can be adjusted, but the current is unlimited, there is no limitation unfortunately.
Okay, so im planning on using this buck converter in combination with a 7s bms to charge a set of li-ion batteries (3 in parallel, 7 in series). if i set the cv to about 30v (4,25 x 7) and the cc to 4,5a (1,5 x 3), would this work to charge this entire setup without damaging the batteries. If the cc and cv work in the right way this should work?
@@robojax but this step down converter has both cc and cv, doesn't this basically mean that it caps the amount of current and voltage the batteries can get? (Say a max of 1,5a per cell till the cell reaches allmost 4.2v and then it tops at 4,2v per cell and will let the current drop. (Maybe smart of me to say I was also planning on using it in combination with a 7s bms
when you set the CV at 12V and CC at 2A, it keeps the voltage 12V and current 2A. once the charge continues, the voltage slowly increases in the battery and as it tries to increase the current is decreased. the CC and CV means lower than those values and NOT higher. So they can go lower.
current does not drop. But voltage always drops on cables. but if you are referring to the voltage drop of the module, it is called "effeciency" and yes. I have shown it in the video.
@@robojax I meant whether the voltage drop occurred on the module itself or on the cables. Or is the voltage drop tolerated in your calculations. Because I've tested one of these modules that turned out to give out 26 Amps at a constant, fixed 1.5V. It was a pulse if you are wondering.
Hello, Great video, lots of useful information. Can I use two converters like this in series, to get 21V out of a single 15V source? or would it be a short circuit if I made like 10,5V and 10,5V of each and join them? Would then the efficiency be very low? Thank you, Sir.
Yes and NO. Yes if you have separate input source for both. No if you have only ONE power source. No efficiency will stay the same. The output would be some of both.
Thanks for the nice video. Can I use this device for charge a 2.6V battery with 20A permanent? I will extend the cooling with big fans. Thanks for help
I don't remember the maximum current this can handle, For sure I always show maximum voltage and current. you come to conclusion from what you see. You are welcome. Please subscribe. I appreciate it and helps my channel grow. Thank you
Caution! This same SZBK07 is advertised on eBay as a 'Buck Boost' converter! * EBay Title = "Step Up DC-DC Converter Step Down 20A 300W Buck Boost". I got stung. It is Buck Only! (Lucky I can use it elsewhere)
Thank you very much for this great upload. I’m looking to buy one of these. I wanted to ask you a question. If the output voltage is set to 7.5V & 20amps would this be safe and could this converter handle it? Thank you
If the width of the heat sing from Amazon is wide enough to cover both heat sinks of this convert, then put it on top of this exactly as it is shown in picture. But you would have to put heat transfer paste between them so there is no gap in between and heat is transferred. If the not wide enough, then just use a fan (exactly the same fan ) should help as well.
Robojax that’s what I was thinking. But I’d like to wire the fan module onto the step down regulator and have the fan draw the power from the buck converter. Do you know where on the converter I could use for the power source? For example this module has a fan added: Step Down Voltage Regulator Board, Yeeco Numerical Control Buck Converter DC 6-40V 32V 24V to 0-38V 5V 9V 12V 8A NC Digital Adjustable Power Supply Module with LED Voltmeter & Heatsink Fan www.amazon.co.uk/dp/B01E8KZG8I/ref=cm_sw_r_cp_api_i_vrpnCbR9BDZWC How could I do this with the module you have used for this video? Many thanks in advance
it depends on your fan and the input voltage. If you fan is 12V and input is 12V, then connect it at input. If output voltage is matching the fan, connect the fan to the output. If the output is very high, then use another regulator like 780X where ix 5, 9, 12, or 15V
Good job bro One doubt this converter connecting 21volt DC, 16 amp current input suitable? My input device is solar panel. Plz give ur valuable information?
Hello, I am de the video to answer such question. perhaps you haven't watched the video. please watch whiteout skipping and I can assure you , you will get the answers. I don't it and have to watch to answer it. so you watch.
The chip is LM5116 and it get hot when I'm connecting it to a 44v without any load. I don't know what happens if i draw load! Not sure to use it or not
@@robertcameron7835thanks. The problem is I'm using an amplifier transformer which it's output voltage varry during the day, between 41 to 44. The ac v is 30v but after rectification it's almost 44v
@@e.a297 That's a very low drop for a diode even Schottky diodes are usually more than that (did you measure that voltage drop with a load on the diode). I would have expected a drop of at least 0.7V or more for conventional diodes under load conditions, Maybe try a different type of diode, you can also put more than one in series. The other thing you should consider changing is the capacitors check the data sheet and see if there is any recommendations.
hello! I have bought this buck converter but, it cant hold a constant voltage and when i put a load on it the voltage drops significantly. and also can i use this for my home made li-ion 37v battery to reduce the voltage to 12v? good video btw!
Hello, Voltage drop is due to current setting. when the current reach to set value, in order to keep the current constant, the voltage is reduces. try increasing the current using potentiometer to maximum. it should work.
Sí, puede conectarlo solo en paralelo SI puede establecer voltajes de salida exactos en ambos módulos. La conexión en serie no funcionará. Estamos trabajando en un canal separado sobre energía y suministro de energía. Véalo aquí ua-cam.com/users/WattHourvideos
this is buck which meant it will reduce the voltage and increase the current. Always remember it is the Power that can not change. voltage and current can always be reduced or increased.
If I hook my 18v 100w solar panel to this and set the output voltage to about 14v to charge a lead acid battery, can I leave it on all the time will it overcharge the battery? Thanks
Hi, you have to know how charge happens. you set the maximum current AND maximum voltage for your battery. For example 14V. if your solar panel's voltage goes lower than 14V the charger will turn OFF. but any voltage above 14 will charge your battery. I will make video on this topic using different modules. stay tuned.
this module is make for 20A. the variable resistors have tolerance of 5% or 10% and that is the first thing you have to consider. Then the OpAmp and components used and the shunt resistor they all affect it. unfortunately I did not pay attention that but it is very good point. I will consider that in the future videos.
HI Sir, Your review is amazing. Can I use this converter in Solar Panel for battery charging? After battery full charge power supply auto cut off or not. Led indication i will get or not. Pls do the needful for the same.
just do the math. Voltage and Current (i) with unit A, V x A = Power, Output power can never be the same as the input because of loss in the conversion process. For example for output of 9V and 15A 9Vx15A= 135W so your input should be higher than input (I have mentioned the efficiency in the video) . if efficiency is 90% (10% loss), then 135W + 10% loss , we have 135 x 1.10= 148.5W or ≈ 150W, then 150W ÷ 12V= 12.5A. So if you have 12.5A at input with 12V, you should get 9V and 15A at output.
you should know the meaning of Power. Power=V*I= 12*2=24W you can get only 24W - 15% to 20% losses. do the same math on the output. You can never get more Power but you can get higher current like 5A at output then 24W÷5A=4.8V or if you want 50V at output 24W÷50V=0.48A. As you can see the power is not changing. it is just voltage and current that goes up and down and yes we can do that. I will make a video on that because many people ask questions about it. Make sure to subscribe so you get notified when I post videos.
I don't like it cant handle current adjustment with minimum voltage. I have 1.5v with adjusting current possible under load. Minimum voltage gets me max current, probably because they use the same feedback pin for both. I mean for xl4016 300w.
Hi, yes you can IF and ONLY IF you set the exact output voltage AND maximum current so the current is not limited. have you visited my other channel where it focuses only only power module, chargers and energy? ua-cam.com/users/wattHour
the multiturn potentiometer needs 15 to 20 turns until you see the output changes. if input and output is the same then 1- The output voltage is set higher than input or 2-the module is dead.
Great review of this particular converter. I have the exact same converter. My issue with mine is that the output does not increase above 11.5 volts with 12.6 as input. Could you advice? Thanks
Robojax , thanks for letting me know. I am looking for a buck boost converter to power a laptop that requires 20 volts and 7 amps using a 12.6 volts 80ah lith-ion battery. Would you recommend one that can achieve that? Thanks for all you do sir. Have a good day.
You would need 20Vx7A=140W+15%=140x1.15= 161W (minimum) converter. So your input voltage would be 161W÷12V=13.4A so you will need a boost converter that has input power more than 161W and 15A with 10V-15V input that can operate continuously with the mentioned values. This item "claims" 400W www.ebay.ca/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=400W+boost+converter&_sacat=0 with 15A input current and they say "use extra heat sink" so it your choice.
Robojax , thanks for your recommendations and for the equations. The unit you linked is very cheap. I will give it a try. Might even by a couple. Be well sir and may God bless you and your work. Sorry, one more question. How can I find out what size potentiometers it uses. I would like to remove them to re- wire them to some single rotary PoTs
Enjoy, coffee on me. I have a question regarding this particular unit. I don't think you have covered it. But maybe you can take a quick peak. Thanks drive.google.com/file/d/1-D0AeiXDSPdwsKMWCVTV_5RJGYyJGsdr/view?usp=drivesdk I'm having problem understanding how to wire my relay to this meter. I'm using a 40Amp 12v relay.
This is not a charger. If you know how charging work, you can use it. Charging a battery needs a mechanism to control voltage and current so the battery is not damaged. I would not suggest using this as charger unless you monitor the voltage and current based on the battery capacity and voltage.
It would suit charging a Lithium battery - they just need a Const.Current on the way up and a Const.Voltage when nearing the top. (Eg 4.1 CV for a 4.2V max cell) Lead Acid is more involved. Always a good idea to put a diode in the output of any battery charger if there is any chance the power goes off while the charger is connected to the battery. You can get a Schottky 20A diode for a few dollars - they only drop about .6V compared to over 1V for a normal diode.. It will loose about 10Watt at 15A so it needs a good heatsink.
Great review, thanks! I have 2 questions: (1) We always saw this voltage drop. Was it caused by voltage drop between Module and active load? If not, what would you guess if the cause of such ~500mV drop? (2) If the MOSFET was upgraded by another as 2~3 mOhm, I believe power dissipation would be much less. Do you believe it would be worth? Thanks for sharing!
Hi, I think the difference between no load voltage and load voltage can be that high, because you measure voltage without drop over the cables to your dummy load. I can't see any extra cables going from output to a voltmeter. So without considering that you shouldn't say the load regulation is unacceptable, as the circuit has external output resistance applied.
I was watching this and thought exactly the same thing. Needs to do a 4 wire measurement I think or increase the voltage to get the required voltage seen at the load.
@@405line If you watch his other videos, he uses the exact same setup for different modules and some of them fare much better from voltage drop so I don't think it's his setup's fault.
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Hi RoboJax, here a contribution from me that solved my question below. I have used it on a solar panel and yes it does function at least till 42.5Volts. The control chip is a LM5116 which handles 100V. Careful, the capacitor on the module can't. Check the chip there is a LM25116 which handles only max 45V and is similar to the LM5116. See below a picture from the back of the PCB with most components identified. If anyone can tell me what the current limiting circuit looks like I'll be happy to know.
I tested it on a real PV panel of 42.5V and 14.5V out at 10 AMPs It does get hot, extra cooling is needed. The chip runs on 300Khz if I remember right. This means that the 3 strains transformer with 0.7mm wire can be optimized by using one with a smaller diameter but more strains due to skin effect in the copper strains. Putting the MOSFETS in parallel with the same type might help too. The 3.5 Amp gate drive of the LM5116 should handle that. Changing it with a lower RDSon is a better idea. A IRFB3077 75Vds 2.8mOhm RDSon for sale at AliExpress lowers the Temperature
www.holamex.nl/files/img/SMPS%2020A%20parts%20identified.jpg
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The difference in the output when the load are are attached / not attached is because of the resistance of the wires. In this particular setup the wire resistance seems to be around 41 mOhm. If your DC load is capable of doing 4-point measumrents then you can just hookup the voltage probes directly to the DC/DC converter output and then get the true output voltage.
thanks for the insight.
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Your reviews are just amazing brother, it really helps in giving a good thought before ordering these items for our project. Keep up the good work!!
thank you.
Tradu în ROMANA
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The best video of 20A model on UA-cam 👍
I am glad you like it.
Hi, very nice review. One tip, you should put one voltmeter directly on output of converter/pcb because voltage on on your Rigol load is slightly lower due to voltage drop in cables. Buck converter tries to maintain voltage but cant "see" value on the other side of cable.
Hi, thanks. I've fixed that in the later videos. The electronic load as voltages sensor wires which I can connected to the output for just measuring the voltage to show correct reading.
Thank you for taking the time to make this helpful video. I bought this unit form Temu at a very cheap price for the quality of the unit. It should useful many hobby projects.
Use 4 wire measurement system to eliminate wire voltage drop. The module regulates the voltage based upon what voltage is present on the module terminals but there is a voltage drop in wires which carry current from the module to the load. The electronic load measures voltage on its own terminals and not on the module terminals so it is no surprise that you will not get the full output voltage set on the module.
2:54 you was asking about the name of Chip . It is ( LM25116MHX ) from Texas instruments . And it's 40v max input and it's better not to pass 35v input . And have dual mosfet control for the VC and CC.
I get the name after I pop up my'n during sudden input voltage change from 32v to 50v by mistake in my power supply . Everything was fine in test but the DC converter not step down any more and I suspect that this ic was not working and I was not able to find any data sheet about it but I email the company store that in AliExpress from China and they give me the number and I buy 15unit for 5$
Than you very much. I have included the link to the datasheet in the description. it was already there.
Another Great and full detailed video by Robojax. I'm planing to make an mppt solar charge controller and this video helps me a lot. Thanks again Robojax
You are welcome. Please subscribe. I appreciate it and helps my channel grow. Thank you
@@robojax I am your long time Subscriber Ahmad :)
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It seems that your power supply can not handle the current demanded by the Buck and has to steel it from the voltage, that's why you are seeing voltage drops in higher voltage tests.... Suggest to use a higher current voltage supply so it would be able to saturate the Buck properly, otherwise all your tests are null and void or you might say a 20% accuracy level!.... Yes, you might have a lab power supply but they are useless in here, you need an IGBT that's able to produce huge amounts of current to saturate any other Buck converter.....
Hello rj, can you answer my 2 questions.
1. Is a diode needed to prevent back flow for charging a battery or battery can be connected directly to load terminals ?
2. Is there a way to enhance their voc as I see all models come with mostly 40v. Can it be upgraded by swapping out a few components such as input capacitors or so ?
1-No diode needed. this is converter and will not allow current back
2-no you can't change anything. it will not work
Excuse me. In which case this converter may burns a potentiometer. I replaced the embedded potentiometer and I tried another one of 10k and 100k. Same result. Burned. I powered a fan 12V 0.41 A. Thank you.
The test is more correct at standard voltages 12 24 36 48 volt :). For example 36 to 12v 36 to 24volt test :). Thanks a lot of nice reviews you have. Hope you have a cool 36-48 volt power supply :D
You are welcome and thank you for pointing out those points .
🙏🙏 From Sri Lanka. Very informative, thank you very much. It is admirable that how you find time to answer all these questions. Comments from readers also helped me a lot.
You are welcome. The best thank you for me is to subscribe to my channel. Your subscription is stamp of approval and my videos will be suggested to more people and this will help me. I appreciate it. thanks❤️
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4:04 over two years later, i can read the chip on my board. it is JM13AJ LM25116 MH
Thank you for sharing.
Very useful demonstration. Just wondering, how hot is too hot for the heatsink on this kind of device? If I can't keep my finger on it, is that dangerously overheated? Or is that normal?
Yes if it burns your finger, that is above 80C so inside chip junction is 50 or 40C more like 120C and that is right at the edge. So check datasheet and see what is junction temperature.
Thanks for your time in making your review. I wanted to ask a question. If the input on the converter changes does it also mirror the same changes in the output? Or does the output stay the same regardless of any fluctuations of Voltage/Current from the input? Thank you & I look forward to your reply
I have tested and presented that. Output does not change as the input changes.
What I want to see, is how this module can regulate a constant current under different input voltages, I was expecting that you set a specific output voltage and change the input to see how it constant ut can regulate the voltage under such circumstances
you test load rig does not have a 00 gauge wire, the 1 volt drop is caused by your wire in the output, unless you place another voltmeter right on the output, 15A will have a large drop on the wire
00 Gauge wire is rated for 100A to 200A. We need maximum of 20A. But I agree, eliminating voltage drop should have been taken into consideration. Thanks for tip though
@@robojax you could just use a separate voltage tester right on the output port separate from the load wire and there upi can decide on the 0.5vo;t drop in regulation.
yes is overrated but wires have resistances, the voltage drop of 0.5volt for a regulator for it not to pass is very easy, since even a 14 a 20amp rated wire still has a resistance proportional to length and these are working with low voltage.
proper instrumentation test for out voltage regulation will be a separate voltmeter exactly on the output.
you have a good load test equipment, ithe voltage measured is on the load itself, measured with the wire and your are testing large currents. maybe a separate tester on the output to see regulations.
thanks for the reviews anyway
Thank you for sharing your knowledge.
Can i use this to make a mobile charger ? I will parallel 5 usb ports with a current limiting resistor so that the output of each usb port is 5V / 2A.
yes you can but you would have to know the maximum current the battery can handle. It might catch fire if you dont know what you are doing.
awesome, can I used it as a solar charge controller to charge lithium cells?
Yes it could
Can I measure output current by shorting the output or do I need to have a load? I do not have a dummy load and I am planning on using this for some DIY projects, as power supply, and maybe as a battery charger. Nice video by the way but it would have been better if it had CC testing. Thank you!
Normally this is how you set the current. You short circuit the output and set the current.. I have not done it on this module but it should work. You are right I should I have tested it with CC.
@@robojax I was just worried the chip may not support short circuit and end up frying the module. I'll try it when my module arrives. Thank you for the confirmation.
Best to first wind down the CC pot to zero before you short - then bring it up to the desired current. I use a few assorted sizes of car bulbs as Loads. Only a few dollars each.
Thanks for doing these tests, but some of us are okay with raising the input voltage to offset voltage droop. Unfortunately you didn't actually show how many amps this buck converter can handle on a long term basis. I am pretty sure it would melt down at 20 Amps, but it would have been nice to find out the limit...
I agree with you. The result I have presented based how hot under certain current it gets. If the temperature increased I have reduced the current. It is very hard to satisfy everyone with the result.
Thanks again for doing the reviews. They are very informative and you are the only one doing them well. But if you can determine how many amps and how many watts a supply can be used for without overheating, I think this would be very useful for many people. For many of us using high power supplies, the load is fairly constant, so voltage droop is annoying but not debilitating.
Unfortunately, whereas it is unusual to find a product from Germany that doesn't meet its specs, and most products from the US or Japan or Korea meet their specs, in China, the specs are generally just a list of what the board manufacturer thinks a customer might want to see. So it is always a crap shoot to figure out whether it makes sense to buy a no-name Chinese product or pay three times as much for something with a better pedigree...
ats89117 I feel like you've answered your question already; 3 times more it is 🍻🍻😁
If I want to set it to output 5A max, can i directly hook a multimeter to the output terminals and adjust the current limiting potentiometer until the multimeter displays 5 Amps? Or will this damage the buck converter? Btw thank you for these reviews, I've learned a lot from your videos.
yes you can connect. CC or Constant Current means it will limit it.
@@robojax wouldnt that short the buck converter?
CC means it has protection. you have to short circuit it to set the current.
@@robojax ok thank you very much!
you are welcome.
Thanks for the good video! What would happen if you use an input voltage of 42V, that is, a little over 40V?
You are welcome. Something might happen like it might smoke . So it might be dangerous. Unless you try it, you won’t know.
I have the same question. Surmoka, did you try to apply 42v to the input?
It seems to me that you are measuring the output at the load and not at the board so you are seeing a voltage drop across the wires.
Hello sir i have a question .. what will happen if the output terminals shorted ? Does it have a short-circuit protection feature or will the module burn?
Let's say input voltage is 35v 7amp dc .
Thank you so much for the detailed video on this module. I love it
Looks like the main problem with these supplies is the voltage drop at output. With the current limit they are acceptable, at least someone will load it to the acceptable thermal limit, knowing that is only 8A or whatever. But the output drops so much in voltage that is nasty. What chip is the controller, LM25116? And for me, I would choose transistors with lower internal capacitances
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thanks for the video, great stuff. can I connect 2 in parallel to have twice the current at the output?
yes you can. BUT and that is a very important but. you have to set both output exactly the same and both current setting exactly the same. then you can connect them in parallel. if you don't, then if there difference, the current will flow from one to the other one and that is dangerous.
@@robojax what if we connect a Blocking Diode on output of each of these in parallel to prevent current flowing from one buck into another in case of mismatch. Will that be safe.
@@JawaazAhmad yes, that will be fine
Thanks for this review. The efficiency at 15:05 can't be correct with an input of 44.4W and an output of 17.7W. (17 / 44) * 100 = ~38%. Also efficiency is spelled wrong.
Then read values. Thank you.
+1 -- Mr Kowalczyk. Also, I didn't see you confirming that the Current Limit function was not influencing the alleged 'poor regulation', at each new setting. There may be quite a bit of interaction between the two trimpots -- after all, the thing is very compact for these power levels.
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Hi, thanks a lot. Do you know input current when there is no toutput load ?
when we talk about 20A or 20,000mA, 1% of this which is 200mA does not matter. Because most components have 5% to 10% error in them. That's why I did not measure it.
Hello friend, how are you? I ended up buying an equal one and when I connect a device to the power outlet the amperage does not go up being useless, but when I test it without connecting anything to the outlet the amperage works normally, you know what may be happening?
can u you please tell me the function of the switch? is it for soft start on/off or the anything esle? It may not be the power on/off switch.
this has switch. which switch? please point it to the time like 2:30 or so
@@robojax at 1:40😊
I just watched it is says that it turns ON and OFF the module. Simple switch.
@@robojax thanks a lot.... I am a regular viewer of your channel. you are doing what we need to know. Hats off to you.
Hi maybe you can help. I want to use this module in a project but want to relocate the two CV and CC trim pots. I have un soldered them and planned to use some 28awg ribbon cable. Approx 150mm long so that I can mount the trim pots in an accessible place. Is this 28awg wire OK or should I use a thicker cable? I appreciate any advice you can give. Thanks and Happy New year!
These trimmers are there just for the sensing. So, you can use thin cabling.
Have seen some of your videos - they are nicely done and thoroughly put. I wish you good. Thanks for the videos.
One question - how would you conclude the design comments on the unit? Is it rugged and looks long lasting for a continuous heavy duty usage in parallels???
Regards
Theoretically it is not a good idea to connect two of them in parallel as it is very hard to to set exact voltage on both and exact current on both. but you can connect if you can set both at the same value. I have given my opinion, watch the video fully. You haven't subscribed to my channel. I will reply to all Subscriber's 🔔 questions. So make sure to Subscribe.😊
@@robojax Thanks for the opinion. Yes, setting all parameters same.
Already subscribed!
What will happen if the mosfets are changed with higher values ones, is it enough to get rid of the ripples and the heating ?
Pm me can you to install do sola paint of charger..
I didn't have to do this but you can use a tiny amount of Arctic Silver Compound and rub it around the use a magnifying glass
Thanks.
I buy this model . Since they say it's the is a powerful buck converter 20amp . But as I see it's not 20amp . But I think if we change the coil and the capacitors in output you may get a better results . But I don't know how to calculate what coil need for 20A and what capacitors is exactly what need . Can you test by change the coil with bigger coil and less turn ?
You can do it but it would be very hard. You would have to draw the schematic, understand the design, then calculate the values. So it would be very hard.
Hi, nice review. I got the same converter but I lost the capacitor c15. Would you please so kind to tell which value it has?
Hi, I am not sure I where I put it. I will try this evening when I got home to have a look at it.
sorry I just checked my lab and the garage and could not find the module.
No problem thx for your help. I ordered another module because I burned one MOSFET and I did realize that the ones soldered are FAKE, unbelievable!! That's why it can't even get close to 20 amps and working at that current for long time. Anyway I saw a video of a Russian guy that has replaced the MOSFET irfb3607 with irf1404 that he claims to be more powerful in terms of current (80A against 162A), but I don't have a proper knowledge to evaluate this option. If you can please let me know.
I want to control high torque servo like 35KG, i am planning to use this module for 4 servo powering. To get max torque i need 6volt 4 amps. Is it possible to get: --- input 12 volt 4200mah lipo -- want to get 6volt 18amp output??
Hello Sir... Can you help me?... I want to make Power Supply with this module but there is something wrong after I want to try operate. I change the potentio with bourn multi turn. The module die... How can I fix it. In the module there is no sign of burn part... Thank you before.
For more info, I want to make Power Supply Regulation from 36V 5A, and this module.
Hello, most probabaly the power MOSFET or DIODE has died. So you would need to replace the one or both.
Hi. I have 20w 18v solar panel. Is this buck converter effective to charge powerbank (without lead acid battery) ?
Can input and output be common-grounded? There seems to be a shunt between two negative terminals. What happens if you common ground source and load?
normally ground should be common on DC system. I don't have the device in hand as I don't know where I put it with thee volume of items I am getting to make video for.
I didn't understand why you did not crank it up on the output current load to the point of shutdown, like you did with others step down buck converters. That would have been very informative, I was interest in the max current this module could delivery before it quits, or starts screaming.
I did it. As soon the output voltage drops, that is IT it won't work. If I want 12V at 5A at output and it gives 11V it has failed. Doesn't matter if I increase the current to 6A. it is useless if you increase the current it will show (for example) 7A or 10A the voltage will drop more to 10V or 9V . so it doesn't matter.
@@robojax So, it seems this module is a far cry from the claimed 20 Amps / 300 Watts. Shame on the manufacturer for advertising it as able to handle much more than it really can. So far I have been unable to find a review of a Buck Step-Down DC-DC converter that really deliveries more than 5/6 Amps in 12 Volts, on a regular basis and without going too hot(energy lost to heat, instead of putting some extra Amps in the output and keeping the Volts steady).
Hlo sir.. Your review is amazing. I realy love it..
If I will add mosfets to this circuit. Parllely.. It helps in increase amp rating??
Hello, I am glad you liked this. It will not work. you need total modification. The constant current section is checking for specific current and turning the voltage low when it detects certain value.
@@robojax thankuu for the answer..
@@robojax i want to connect input 20v 12amp (240) watt power and at output 15v at max current(may be 15 amp) ... Can it work or not sir.?
if it works or not, I don't know . to answer your question, I have to watch the video. So you watch and see which part is closer to your voltages and decide if it works or not.
I tried to connect 12-24 V DC- brushed motor to this DC-DC, as input I used 12 V battery, Voltage regulating is working normal, if you connect any voltage, as output You can become 1-2 volts less, as input. I could not become >11.2 V from 12 Volt input. Current was about 280 mA and current regulating works not or it need some A current for regulating, Adjustable resistor for current could not change the current 270-280 mA, and I am thinking, if I must send that back (defect) or it is normal...? Later I will try with some powerful motor. If it can give more current, as input, I don't know, you can try or wait answers , who did that already. I think, you can count like this, your output power will be about 5% less, as input power. In your case 20x12=240 -5%=228Watt,, 15Vx15A = 225 Watt, in theory it can that, in practice I don't know.
Good video! With which converter can I get 5V and 15A at the output so that it does not overheat and shut down? Thank you
Pm me can you to install do sola paint of charger..
@@anwin85alon greeting
It's used for electrolysis and stuff like that.
Hi ... overall is a good efficiency ? And can add one another mosfet and rectified diode for more stable in high current and decreasing heat ?
Hi, no. The amount of current depents on the inductor and capacitors and it has been calcualted.
@@robojax thanks , what about efficiency in overall? Is a good buck converter? I want use it for made bench power supply
I have a question. What happens if the input voltage is more than the regulated voltage? For example say I'm trying to get 12 volts from a generator that fluctuates in rpms creating an input voltage range of 5v to 20v and I'm wanting to get 12v constantly.
If input voltage is above the voltage of Capacitors, they will explode. The chip will handle some excess of voltage. I have provided the datasheet. the fluctuation within the input range should not have affect as long as it is just a little above output voltage.
For this converter to work, input voltage must always be over the regulated voltage. On your case, you will be getting 5V-12V at the output. If you want to keep the voltage stable at 12V, you'll have to add a large enough capacitor at the input.
You need a "Buck / Boost" converter if the input voltage can drop below the required output voltage. This one is 'Buck' only - it can only reduce the voltage. 'Buck / Boost's are available on eBay for about the same price.
Hello sir thanks for this review, can i increase my output voltage up to 24vDC with this power module even if my input voltage source is just 12vDC? sorry about my bad english, thank you.
edit:
Would you recommend one that can achieve that?
Hello, this is "Step down" or "Buck converter" so it ALWAYS reduces. if you want to increase then you need "Boost Converter" See my videos on boost converter ua-cam.com/users/robojaxTVsearch?query=boost
If you put a smal cpu fan that would help with power increase?
Hi, someone test with 42V input voltage? I need it to reduce 42V from liion 10S2P.
Hi, see the input capacitors voltage . They will explode if you connect higher voltage.
@@robojax Input is for 50V.
then there must be another reason that is rated at 36V. You may try it at your own risk.
@@krisg8634 I have the same question. Did you test it? I want to use the battery from my e-scooter, which has the same 10s li-ion
Hi i know this is a very stupid question. I am now starting to learn about motherboard repair and in need for power supply that can supply high volt an variable ampere. My question is can if i set this to let say 20V, and i didnt touch the potentiometer at all, will it supply the needed ampere required from the load or it will stay stuck at a certain ampere and i will have ti match it with the load. Thanks!
Hi, no question is stupid question. For power remember P(input)=P(output)-15% meaning output will always be less due to losses. So you can calculate the power easily P=VxI where I is current in A unit. yes Const current means it will keep the current constant and not changed. but this is only possible if the input can supply the needed current. Remember the outpt P can't be higher the input P or Power.
Lo siento, (google) no lo entendí. Por favor, use una oración muy simple para que Google me la traduzca.
Robojax understood! Thanks for the tips! I have just ordered the parts and are waiting. Cant wait to assemble them my self! Thanks a lot!!
Will this stop feedback from charging a 14.4v trolling motor for solar when charged or charging at nightfall? Not damaging the converter?
what is trolling motor?
@@robojax It's a motor that works similar to a boat engine, it allows you to travel slowly on water.
Hi RoboJax thanks for the clear video. I have a question and I hope you can help me. I want to use this module on a 72Cell 300Watt solar panels with a Open voltage Vco of 43V. That just outside the absolute maximum ratings of the TL8711. This TL8711 seem to be, but is not fore sure , the 20Pin control chip at the back of the module. Your video is posted on UA-cam with a picture indicating that this module is tested for 6..60V input voltages. The content of you video only shows 30V and lower input voltages. Can you tell me if you really have tested this module successful at voltage till 60V?. Is the Vcc of the control chip directly coming from the input or is that coming from a regulator meaning the max input voltage is determent by this regulator and the max Vds of the FET's being used. Hope you can tell me that.
would you please send me the time like 4:51. I am sorry I have over 230 videos and have to replay to comments. this would make it easy for me.
Can i upgraded amp using more MOSFET this converter
By the design, NO . To increase the current , both capacitors and inductor are the main components to change and increase the current. Then you will look at proper mosfet to handle that current
You didn’t reply?
Bro you make a video use this board and use more mosefet in parallel and get more amp
You didn't short circuit and set constant current?
Nice video. got exactly the same thing given to me but is missing a componentand have not tested it yet. Would you be kind enough to measure or give me the value of C15 (filter cap on CV out potentiometer). Thanks in advance.
I will try to review this again. You haven't subscribed to my channel. I will reply to all Subscriber's 🔔 questions. So make sure to Subscribe.😊
Hello, the voltage can be adjusted in my product, but current limitation cannot be made. What could be the reason, do you have any information? Thanks.
Hello, unless the potentiometer is broken or the module is bad there is not other information. I assume that you followed the video. Please subscribe. I appreciate it and helps my channel grow. Thank you
@@robojax Thanks, I inserted a different potentiometer thinking it might be broken but the result did not change. the voltage can be adjusted, but the current is unlimited, there is no limitation unfortunately.
Okay, so im planning on using this buck converter in combination with a 7s bms to charge a set of li-ion batteries (3 in parallel, 7 in series). if i set the cv to about 30v (4,25 x 7) and the cc to 4,5a (1,5 x 3), would this work to charge this entire setup without damaging the batteries. If the cc and cv work in the right way this should work?
first of all this is NOT a charger. Charger monitors voltage and current and makes adjustments. But if you monitor it manually it will work.
@@robojax but this step down converter has both cc and cv, doesn't this basically mean that it caps the amount of current and voltage the batteries can get? (Say a max of 1,5a per cell till the cell reaches allmost 4.2v and then it tops at 4,2v per cell and will let the current drop. (Maybe smart of me to say I was also planning on using it in combination with a 7s bms
when you set the CV at 12V and CC at 2A, it keeps the voltage 12V and current 2A. once the charge continues, the voltage slowly increases in the battery and as it tries to increase the current is decreased. the CC and CV means lower than those values and NOT higher. So they can go lower.
Is the voltage drop occurring in the module itself or on the cables. Is the voltage drop on the cables tolerable in this test?
current does not drop. But voltage always drops on cables. but if you are referring to the voltage drop of the module, it is called "effeciency" and yes. I have shown it in the video.
@@robojax I meant whether the voltage drop occurred on the module itself or on the cables. Or is the voltage drop tolerated in your calculations. Because I've tested one of these modules that turned out to give out 26 Amps at a constant, fixed 1.5V. It was a pulse if you are wondering.
Hello, Great video, lots of useful information. Can I use two converters like this in series, to get 21V out of a single 15V source? or would it be a short circuit if I made like 10,5V and 10,5V of each and join them? Would then the efficiency be very low? Thank you, Sir.
Yes and NO. Yes if you have separate input source for both. No if you have only ONE power source. No efficiency will stay the same. The output would be some of both.
@@robojax I see, thank you :)
Thanks for the nice video. Can I use this device for charge a 2.6V battery with 20A permanent? I will extend the cooling with big fans. Thanks for help
I don't remember the maximum current this can handle, For sure I always show maximum voltage and current. you come to conclusion from what you see. You are welcome. Please subscribe. I appreciate it and helps my channel grow. Thank you
Caution! This same SZBK07 is advertised on eBay as a 'Buck Boost' converter! * EBay Title = "Step Up DC-DC Converter Step Down 20A 300W Buck Boost". I got stung. It is Buck Only! (Lucky I can use it elsewhere)
Thank you very much for this great upload. I’m looking to buy one of these. I wanted to ask you a question. If the output voltage is set to 7.5V & 20amps would this be safe and could this converter handle it? Thank you
You are welcome. I have presented my findings. It is you to determine if it works for particular application or not.
If the width of the heat sing from Amazon is wide enough to cover both heat sinks of this convert, then put it on top of this exactly as it is shown in picture. But you would have to put heat transfer paste between them so there is no gap in between and heat is transferred. If the not wide enough, then just use a fan (exactly the same fan ) should help as well.
Robojax that’s what I was thinking. But I’d like to wire the fan module onto the step down regulator and have the fan draw the power from the buck converter. Do you know where on the converter I could use for the power source? For example this module has a fan added:
Step Down Voltage Regulator Board, Yeeco Numerical Control Buck Converter DC 6-40V 32V 24V to 0-38V 5V 9V 12V 8A NC Digital Adjustable Power Supply Module with LED Voltmeter & Heatsink Fan www.amazon.co.uk/dp/B01E8KZG8I/ref=cm_sw_r_cp_api_i_vrpnCbR9BDZWC
How could I do this with the module you have used for this video? Many thanks in advance
it depends on your fan and the input voltage. If you fan is 12V and input is 12V, then connect it at input. If output voltage is matching the fan, connect the fan to the output. If the output is very high, then use another regulator like 780X where ix 5, 9, 12, or 15V
Good job bro
One doubt this converter connecting 21volt DC, 16 amp current input suitable?
My input device is solar panel.
Plz give ur valuable information?
Hello, I am de the video to answer such question. perhaps you haven't watched the video. please watch whiteout skipping and I can assure you , you will get the answers. I don't it and have to watch to answer it. so you watch.
What program are you using??? I’m trying to get a tec to 15v 10 amp....I’m not smart with any of this. I have a buck and 24v 14a power supply.
it is Rigol Electronic Load that has PC software. I just put the link in the description for that.
@@robojax thanks for the reply. Another sub. Thank you.
you are welcome and thanks for subbing.
The chip is LM5116 and it get hot when I'm connecting it to a 44v without any load. I don't know what happens if i draw load!
Not sure to use it or not
Think you misread the chip or a typo, it's a LM25116 and it's maximum input voltage is 42V according to the data-sheet.
@@robertcameron7835thanks. The problem is I'm using an amplifier transformer which it's output voltage varry during the day, between 41 to 44.
The ac v is 30v but after rectification it's almost 44v
@@e.a297 You could put some diodes in line between rectifier and module to reduce the voltage.
@@robertcameron7835 i tried it and it drop only 300mv
@@e.a297 That's a very low drop for a diode even Schottky diodes are usually more than that (did you measure that voltage drop with a load on the diode). I would have expected a drop of at least 0.7V or more for conventional diodes under load conditions, Maybe try a different type of diode, you can also put more than one in series. The other thing you should consider changing is the capacitors check the data sheet and see if there is any recommendations.
hello! I have bought this buck converter but, it cant hold a constant voltage and when i put a load on it the voltage drops significantly. and also can i use this for my home made li-ion 37v battery to reduce the voltage to 12v? good video btw!
Hello, Voltage drop is due to current setting. when the current reach to set value, in order to keep the current constant, the voltage is reduces. try increasing the current using potentiometer to maximum. it should work.
Es posible estos módulos conectar en paralelo o serie entre si? Quiero ponerlo en aplicación a placa solar de 24v a 12v.
Sí, puede conectarlo solo en paralelo SI puede establecer voltajes de salida exactos en ambos módulos. La conexión en serie no funcionará. Estamos trabajando en un canal separado sobre energía y suministro de energía. Véalo aquí ua-cam.com/users/WattHourvideos
Can this be used as a solar panel regulator to charge battery that would boost amps from solar.
this is buck which meant it will reduce the voltage and increase the current. Always remember it is the Power that can not change. voltage and current can always be reduced or increased.
Can I use this circuit to limit current. For example if I input 12v from a battery and get output of 12v with limit of 10 amps. Is this possible?
Thanks in Advance. You have explained everything about this circuit very clearly. Very nice review.
That feature is called Constant Current or CC. I don’t remember what I did in this video but if it has CC feature I should have explained it
Hello my friend can you give me diagram link for this buck converter not only irfb 3607 ..I need datasheet to make pcb.
Hi, you won’t find it . You gotta buy one tans draw it.
@@robojax I failed to draw it.. some tracks are hidden.can you help me ?
ما هو أقصى جهد مسموح ادخاله هل يصل حتى ٤٠ فولت وفي حال ادخال فولت أعلى هل تخرب الدارة
I mentioned the maximum input voltage in the video. When we say maximum it means you can fit above that value. As Simple as that.
If I hook my 18v 100w solar panel to this and set the output voltage to about 14v to charge a lead acid battery, can I leave it on all the time will it overcharge the battery? Thanks
Hi, you have to know how charge happens. you set the maximum current AND maximum voltage for your battery. For example 14V. if your solar panel's voltage goes lower than 14V the charger will turn OFF. but any voltage above 14 will charge your battery. I will make video on this topic using different modules. stay tuned.
The IC you could not read the name is not dremmeled out on ine.It is a LM25116
I already have the datasheet link in the description. Thanks
Hi. What is the chip U3 marking? My module is delivered damaged without this chip :(
Lm25116
Have you measured the voltage at the source?? I think the cables are dropping the voltage
I used very thick wire from source. So no worries.
Thanks man for this review!
Pm me can you to install do sola paint of charger..
Please how do you regulate the output current from this buck converter
Please learn it from this video ua-cam.com/video/xSI9k5BK-jU/v-deo.html this is my other channel .
8:03
Wow it's working like an mppt. Boosting amps !
LOL
Hi, i want use this to control the current, how is the max ampere if i use input 13v and output 12v?
I presented this test. You should come to conclusion by watching the video.
Witam zrobiłem zwarcie na wyjściu przy minimalnych ustawieniach volt i amper, co mogło się uszkodzić.
Pm me can you to install do sola paint of charger..
Since how many amper (mA) begin it to regulate current?
this module is make for 20A. the variable resistors have tolerance of 5% or 10% and that is the first thing you have to consider. Then the OpAmp and components used and the shunt resistor they all affect it. unfortunately I did not pay attention that but it is very good point. I will consider that in the future videos.
@@robojax thanks for answer, my module is 15A, I sow another video, in which one blogger try to reduce current with this module, but after
ua-cam.com/video/Karc-o81v9M/v-deo.html
HI Sir, Your review is amazing. Can I use this converter in Solar Panel for battery charging? After battery full charge power supply auto cut off or not. Led indication i will get or not. Pls do the needful for the same.
Hi, yes it can be used.
@@robojax i think it is not design for charging battery. I dont see any diode on the circuit to prevent current coming from the battery
At 12v input and 9v output can it reach 15 Amps for a project or the 9 Amps is the max for these volts? Thank you
just do the math. Voltage and Current (i) with unit A, V x A = Power, Output power can never be the same as the input because of loss in the conversion process. For example for output of 9V and 15A 9Vx15A= 135W so your input should be higher than input (I have mentioned the efficiency in the video) . if efficiency is 90% (10% loss), then 135W + 10% loss , we have 135 x 1.10= 148.5W or ≈ 150W, then 150W ÷ 12V= 12.5A. So if you have 12.5A at input with 12V, you should get 9V and 15A at output.
@@robojax do you think it is reliable to use it in a rc car or is it just too much for it ? Thank you
Why output current is more than input current??...can i increase solar panel ampere by this buck converter???
you should know the meaning of Power. Power=V*I= 12*2=24W you can get only 24W - 15% to 20% losses. do the same math on the output. You can never get more Power but you can get higher current like 5A at output then 24W÷5A=4.8V or if you want 50V at output 24W÷50V=0.48A. As you can see the power is not changing. it is just voltage and current that goes up and down and yes we can do that. I will make a video on that because many people ask questions about it. Make sure to subscribe so you get notified when I post videos.
I don't like it cant handle current adjustment with minimum voltage. I have 1.5v with adjusting current possible under load. Minimum voltage gets me max current, probably because they use the same feedback pin for both. I mean for xl4016 300w.
Can i join 2 converter in Perallal with same voltage for 40Amp? Just I need 13v 40A output. Please ans......
Hi, yes you can IF and ONLY IF you set the exact output voltage AND maximum current so the current is not limited. have you visited my other channel where it focuses only only power module, chargers and energy? ua-cam.com/users/wattHour
Which IC is used for the regulation of voltage?
Please bread the comments it has been mentioned
i cant get this thing workin...
when i connect a 12v battery nothing happens when i turn it on, no output.
same with all other batteries.
the multiturn potentiometer needs 15 to 20 turns until you see the output changes. if input and output is the same then 1- The output voltage is set higher than input or 2-the module is dead.
Can i know which sendust core is used in the buck converter
What is sendust?
Great review of this particular converter. I have the exact same converter. My issue with mine is that the output does not increase above 11.5 volts with 12.6 as input. Could you advice? Thanks
this is "buck" converter which means it ALWAYS reduces the voltage and never increase.
Robojax , thanks for letting me know. I am looking for a buck boost converter to power a laptop that requires 20 volts and 7 amps using a 12.6 volts 80ah lith-ion battery. Would you recommend one that can achieve that? Thanks for all you do sir. Have a good day.
You would need 20Vx7A=140W+15%=140x1.15= 161W (minimum) converter. So your input voltage would be 161W÷12V=13.4A so you will need a boost converter that has input power more than 161W and 15A with 10V-15V input that can operate continuously with the mentioned values. This item "claims" 400W www.ebay.ca/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=400W+boost+converter&_sacat=0 with 15A input current and they say "use extra heat sink" so it your choice.
Robojax , thanks for your recommendations and for the equations. The unit you linked is very cheap. I will give it a try. Might even by a couple. Be well sir and may God bless you and your work. Sorry, one more question. How can I find out what size potentiometers it uses. I would like to remove them to re- wire them to some single rotary PoTs
Enjoy, coffee on me. I have a question regarding this particular unit. I don't think you have covered it. But maybe you can take a quick peak. Thanks
drive.google.com/file/d/1-D0AeiXDSPdwsKMWCVTV_5RJGYyJGsdr/view?usp=drivesdk
I'm having problem understanding how to wire my relay to this meter. I'm using a 40Amp 12v relay.
I have a question I have solar 40v I need 14.6v out put
Can I use 2 wells in series to reduce the voltage by 60 volts?
Yes you can but keep in mind that GND is common.
can i charge the battery directly using this buck converter? or i need a diode for reverse protection? pls help. thanks
This is not a charger. If you know how charging work, you can use it. Charging a battery needs a mechanism to control voltage and current so the battery is not damaged. I would not suggest using this as charger unless you monitor the voltage and current based on the battery capacity and voltage.
Thank you
You are welcome.
It would suit charging a Lithium battery - they just need a Const.Current on the way up and a Const.Voltage when nearing the top. (Eg 4.1 CV for a 4.2V max cell) Lead Acid is more involved. Always a good idea to put a diode in the output of any battery charger if there is any chance the power goes off while the charger is connected to the battery. You can get a Schottky 20A diode for a few dollars - they only drop about .6V compared to over 1V for a normal diode.. It will loose about 10Watt at 15A so it needs a good heatsink.
Great review, thanks! I have 2 questions: (1) We always saw this voltage drop. Was it caused by voltage drop between Module and active load? If not, what would you guess if the cause of such ~500mV drop?
(2) If the MOSFET was upgraded by another as 2~3 mOhm, I believe power dissipation would be much less. Do you believe it would be worth?
Thanks for sharing!
Kya yah 10 volt se 15 volt kar sakta hai maine bhi yah liya tha usse nahin ho raha hai
? English or Farsi please
Change 9 volt to 14.5 volt this bord increase
can i supply with accu 28volt70ah ??(2 pieces accu 12v70ah with series circuit)
Voltage is voltage . You can connect from any source