Testing the DPS5015 Power Supply Module

[@immrnoidall]

WE ARE SO LUCKY TO LIVE IN A TIME WHERE THESE EDUCATIONAL VIDEOS,ARE EASY TO FIND AND TO BE ABLE TO BUY THESE ELECTRONICS FOR MOST ANY APPLICATION,AND HAVE IT DELIVERED TO OUR HOUSE, REALLY IS AMAZING. GREAT TIMES WE LIVE IN. I LOVE TO TINKER AND BUILD.

[@1959Berre]

Why are you shouting?

[@immrnoidall]

lol

[@juanabreu5127]

According to what you say at 37:30, if while your are charging a battery, an utility power failure occurs, your DPS5015 module is going to get burnt. I gather this module should not be used as a battery charger unless a blocking diode were placed in series with the output. Thanks for sharing your findings.

[@neutronstorm]

HI Juan, thanks for the comment. I was just reading what the instructions said so I am not really sure what they mean. It's a good point you make about what would happen if you lost power at the input. I have no idea. With regard to using it to charge a battery, according to the banggood page ( in the description ) it *is* ok to use to change a battery so I assume this means it does have a blocking diode as one of the other modules specifically mentioned that it needs an external diode.

[@rdtech9153]

Juan Abreu Hi friend this DPS5015 don't need a diode when you charging the battery. because there is a diode circuit on PCB. you don't need add it . but you must pay attention, when you charge the battery, don't let polarity reverse, otherwise it will be burnt.

[@rdtech9153]

neutronstorm Hi , you can't see this from bangood . because thery are just our reseller. they don't know technology about this . let me explain this. this DPS5015 don't need a diode when you charging the battery. because there is a diode circuit on PCB. and when you only disconnect input, it will don't damage DPS5015, don't worry about this. you don't need add it . but you must pay attention, when you charge the battery, don't let polarity reverse, otherwise it will be burnt. understand

[@bunch8]

Hello RD Tech. When you say that reversing the polarity when charging a battery it will be burnt, do you mean that the PCB will be destroyed if a battery is connected the wrong way or that the battery will be destroyed?

[@rdtech9153]

Bunch Hi friend , yes, the PCB will be destroyed, for the damaged degree, it depends the current for the battery, if the current is small, battery is ok. but if it is big, the battery will be damaged too. thank you.

[@nigellyttleton]

Glad to see you stopped the wiring on the output modules it makes more sense that way. Great vid.

[@nigellyttleton]

Swopped that is not stopped. Damn auto correct gets me every time

[@neutronstorm]

I am guessing you meant "swapped" :) Yea ocasionally my brain works well enough to get something right! In the end it worked out quite well and I am happy with the results. I have just received a new DPS5015 to swap in place of the one that's got the slightly off readings so I will see how that goes.

[@peskandritsas06]

very good job on the construction neutronstorm and fabulous gadget from theketsa... thank you all!

[@rdtech9153]

Hi friend , good work , I am comming I saw the problem you talked about it is the left one. when in the CC mode, the setting current is less 0.09A than the display value ,right ? when in 15A, less than 0.04A, righ? the right one did not have this problem, right ? it is error between setting value and display value. it is nomal. because there is alway error between real value and setting value （or display value ）, it is nomal . I saw your error is bigger, I guss it caused by PCB mechanical deformation from some pressure. and when something toch the sampling resistance (constantan wire), those can cause this error. there is a way to decrease this error, not delate. disconnect all things ( input power and load ), then keep pressing the SET key and then connect input power supply , until the LCD display lights, you can losse the button, then the calibartion is done so it decease this error so you can try

[@rdtech9153]

it is not my products case you can refer this case 1, The housing for DP30V5A, DP50V5A, DP3003, DPS3005, DPS5005 : www.aliexpress.com/store/product/RD-DP-and-DP-Power-Supply-housing-Constant-Voltage-current-Step-down-casing-Programmable-digital-buck/923042_32795699939.html?spm=2114.12010108.1000023.15.KpZGLj 2, The housing for DPS5015, DPS3012 and DPH3205:　 www.aliexpress.com/store/product/RD-DPS5015-DPS3012-DPH3205-Power-Supply-housing-Constant-Voltage-current-casing-digital-control-buck-Voltage-converter/923042_32794029335.html?spm=2114.12010108.1000023.16.KpZGLj

[@TzOk]

The meter in the left module module was showing some current (and power) also when there was no load at all... look at 10:00 - 0.01A and 0.14W at 14.20V with no load on the output.

[@the22fu]

Can someone tell me how to run this in constant current mode? Mine always runs in constant voltage mode which is quiete annoying since the power supply is sometimes not abled to detect a high ampere load. For example I have a 100W hand vacuum cleaner for my bench and without the CC mode I only get the 100W out of it when I double the input voltage from 12 to 24 volts. It is originally designed for cars. Normally it uses 8,3 amps but in cv mode it just uses about 2,4 amps to about 4,2 amps. Besides that it is a really awesome bench power supply!

[@adm.tecnologo2242]

Rd Tech Can I use a 17 Volt 70 Amp Dc transformer or source rectified and filtered on this DPS5020?

[@BadMax02_VR]

@@adm.tecnologo2242 you could but would only be ablke to set abpout 0-15v on the modul output

[@chuck5761]

I suspect the phrase "if you connect the supply power with output, the module will be burnt" means that if you wire it backwards (power source to output, load to input) it will burn out. In your case, if you connect the battery with the meanwell turned off, it may go up in smoke.

[@bills7115]

I just got one of these units hooked it up to a Deltron 24v 21 amp PSU. I haven't messed with the current part but the Voltage reads exactly like the unit on the right .01v higher then my BM829 meter reads. To get the 50v I am going to power the 5015 through a 20 amp boost converter. Not sure what I will wind up with current wise at 50 volts but it should be fairly close. Never used a boost before. I don't much work with much above 13.8 v anyway. I was going to run 2 of the units or maybe the 3012 32v 12 amp unit but I have changed my mind after seeing this vid. and I thank you for that. Instead I think I will use bucks to drop to 9v, 5v, 13.8v They won't have current control easily controllable but If I need that I'll use the 5015 outs. I will save a bit of money on a box and the use of the bucks. You have a very nice PSU but the fan noise is Hellracious. The Deltron has no fan it is very beefy in its build so I guess it doesn't need one. Thanks again for the great vid.

[@neutronstorm]

Thanks Bill, yes the power supply is noisy but it is an awesome supply. It actually has separate external voltage sence connectors so I could set it up in another room in a "4 wire configuration" with long cables to my work bench and it would automatically compensate for the voltage drop of the cables and still produce a smooth 48v. It has other really nice features like it monitors it's own output and will only supply 48v or 0v. It doesn't go over or under even during power up or power down. I actually purchased it to power my iCharger 4010duo - www.progressiverc.com/icharger-4010duo.html and it's awesome for that. I would like to build a solar system with a 48v battery bank to power all of these device but that is still a little way off. The 48v supply was good for testing the device as I can test it over a wide voltage range and also know that there is no way that the 48v supply is going to be an issue in the test ( except for the noise ). I actually moved it out and around the corner for most of the video trying to keep the racket down! If I want to run silent, I use the big 40AH Lifepo4 battery I show in the video as the power source. It's good for most loads where 12 volts or lower output are required. The Deltron supplies looks neat. I hadn't seen them before so I will keep them in mind. Thanks.

[@bills7115]

I got mine used for $29 weighs a few pounds, big beefy caps, 2 transformers only 2 screw posts for out but they are 1/4 inch. It has an led connector which is a plus came with a green led on a foot long cord. the model is V501D 1989 date. it is larger then I thought it was 10.5x4.75x2.5 inches. At 21 amps I have plenty of current for what I want to do. Going to play with Bucks for 9v, 5v, 3.3v, 13.8v going to put external 10 turn pots to adjust current on the 5v and 3.3v. 9v is to run kits like LSR, clocks etc. It will be 5 amps max. 13.8v 15 amps max, 5v, 3.3v 10 amps adjustable. Also some of those V/A led meters from e-bay for the 5v, 3.3 amps. Need to find a decent box for it. It is and over the top project for winter, snow and ice on the ground, 15f is warm.

[@Subgunman]

Very nice, neat, professional build! Another source for DC circuit breakers are the car stereo sales and installation houses, especially those which like to build competition car audio systems.

[@neutronstorm]

Subgunman thanks for the comment. Good idea about the car stereo parts but I bet they are super expensive being car stereo components. They probably also have flashing neon lights all over them as well😜

[@PerBuch]

Calibrate the left unit (press "set" on power up). And clean the display contacts on your Fluke :-)

[@neutronstorm]

Hi Per. Thanks for the comment. The "set" power on trick only calibrates the zero current reading and didn't help in my case. RD Tech seems to think that this can happen if the current shunts get bent or damaged. The thing that I was confused about is that the device actually limits at the correct voltage and current as shown by when it changes from CV to CC but the voltage on the display seems to be a bit out. There must be more then one voltage / current sense device I am guessing and it appears that these can diverge. Yes I will clean up the fluke. It's a very old meter ( probably more then 25 years ). I have cleaned the contacts in the past but they obviously need another clean and it didn't occur to be to do this before the video. Maybe I will make a video of me cleaning it and it might help someone else.

[@pirateman1966]

If you would've placed the holes for the output jacks, a few inches back, you wouldn't have had to resort to crossing the wires like that, adding more resistance, copper and weight. Besides that, I enjoyed seeing your workmanship.

[@philoso377]

Nice presentation. My DPS5 reads 0.01 Amp higher than actual. Inspection at the current sensing resistors appears installed in a fast pace production line. We can see only solder dome (not fillet) at the bottom side and little to none solder flow to top side. Leaving the plated through via (cylinder) embedded in series with the sensing resistors, to a higher than expected current reading. I can't resist that went ahead solder touch up the joints, one at a time between test (six of them) reflow then add solder to the top. I got it down to +/-0.05 Amp error when done. In my case, I only need to touch up two out of six joints. By the way, some clamp meter has a higher uncertainty than a fluke multimeter in Amp scale. Hope this helps

[@neutronstorm]

Hi YK, I will check the soldering on my units to see if that helps. Please note that their is a procedure to zero the device if it's reading .01 higher even when not connected. In the video I wasn't measuring or commenting about the absolute accuracy of the device. I don't have the test gear to test. My comment was that the device isn't internally consistant. For example, when you set the limit to X the device will exceed that limit and show on the display X + 0.05 for example. All I was saying is that if the device think's it's 0.05 over, why doesn't it just reduce the output to X? Also, this problem only affected one of my devices so perhaps it was a below average sample. Thanks for the comment and the tip about the solder.

[@BadMax02_VR]

i have a question can you with these 2 modules on the same supllie but these to modules in series to get 15a and 100v so are they isolated and can you get more than the inputvoltage like that? or are they going to short circuit or something? could you maxbe try it with 1v so that you dont burn anything and see if you get 2 volt when put in series?

[@davidgeltz7604]

You swapped the wiring on the output modules but not the breakers the left one kills the right side output and right one kills the left side output .

[@neutronstorm]

Good point. I guess if the breaker ever fired I would probably be pulling the thing apart trying to work out that went wrong anyway as the breakers are for a lot higher current then would typically be expected. These breakers aren't ones you can switch off ( only reset ) so hopefully I will never have to touch them. I guess I could swap the wires on the tabs fairly easily if needed, I think the cables might be long enough.

[@jimc52]

Cooling? How hot is the unit getting? I would like to know what fuse boxes those are please. WhT power source we're you using that was humming in the background?

[@neutronstorm]

James Clark hi there. They didn't get very hot. My calculations in the video showed that they weren't dissipating all that much power as they seemed to by efficient in my test. I finger tested the coil and the heatsink and they were not hot. With respect to the fuses, they were from jaycar. I believe it was this device www.jaycar.com.au/20-amp-circuit-breaker/p/SF2260 Hope this helps.

[@jimc52]

Thanks a bunch!

[@neutronstorm]

James Clark the power supply is a Meanwell RSP-2400-48 at 240v ac input. It's in the video description and I think there is some footage of it in the video. Sorry about the noise but it's an awesome supply.

[@ManuelMcLure]

I'm looking at using some of the lower-power versions of these (like the DPS3003) to make a dual output power supply and I'm wondering if the outputs on these are floating so you can tie the negative of one to the positive of the other to get -/common/+ voltages for op amp use?

[@themasterofdisaster1]

The grounds are always connected. You need to power it with two separate power supplies. You can use two DPS-600. Very reliable, cheap (used out of old servers for about 8-14 euros) and with a big power headroom. It's relatively easy to disconnect the case ground from the negativ output. Have a look here: djblue81.wixsite.com/modellbau/umbauanleitung-hp-dps600pb-b (use google translate, it's a german blog)

[@neutronstorm]

Hi Manuel, thanks for the comment. I haven't tested the DPS3003 but I would be highly suprised if they were isolated. I believe they would be the same as the device I tested which is NOT isolated. By not isolated, it means you can NOT common them up in parallel or series. If you parallel them up, you will get inaccurate current readings as I believe the current shunt is in the negative wire. If you connect them in series they will short out and blowup. If you wanted to do this, you would need to power them with with isolated input supplies. You could do this by building a power supply with two transformers that feed the two DPS3003's seprately. Alternatively you could find a single transformer that had two separate isolated output windings. You would of course need two separate rectifiers and two separate sets of smoothing caps as well. This is what a bench power supply typically has and is why they are so much more expensive. In essence, you need a transformer somewhere in the power supply to isolate them. Transformers can pass AC but they won''t allow DC to pass from the input to the output.

[@ManuelMcLure]

Thanks for the reply. I was hoping that this was actually a mini switched-mode power supply in disguise instead of just a buck converter, but it looks like that hope was dashed. Oh, well - I still picked up one of the DPH3205 units to be combined with a 12V/13A power supply to make a nice single output bench power supply.

[@borayurt66]

How hot do the regulators get inside that box? I have something similar in my mind, using a lineer power supply instead of a smps like you used, and I plan to put everyting in one box.

[@neutronstorm]

The DC to DC converter is a different design to a linear power supply. The linear power supply burns off excess power as heat where as the DC to DC converter only heats up the devices doing the switching and to some extent heat due to large current running through the tracks and coils. When dropping from a high voltage to a low voltage ( say 50v to 5v ) the DC to DC will do that efficiently ( 90% loss) as heat making it fairly useless. Linear power supplies match the input voltage more closely to the output voltage in practice ( say 8v input for 5v output ) making the losses acceptable. The upside of linear power supplies is that they are a much more stable supply ( much less AC noise on the DC output ). This might be important when powering delicate circuits for example powering a microprocessor directly but it isn't important when your using the power supply to charge a battery or power something that has it's own internal regulation circuit. To answer your question, the switching devices under the fan don't seem to output allo that much heat in my testing however I didn't really test it beyond putting my finger on it. I also didn't test it over a wide range of input and output voltage combinations. My case has some holes for air flow and I did try to put the modules and the fans as close as possible to the holes. I haven't noticed that case getting warm at all and I haven't had any problems with the modules over heating at this stage. Thanks for your comment.

[@borayurt66]

Thank you for this detailed explanation. Just ordered one. Hope that it won't be like the one you have on the left. :D

[@Stefan_Van_pellicom]

So your right hand connector set is protected by the left hand fuse and vice versa ? Weird ...

[@3D_Printing]

Neat job, 11:16 take care touching bulbs, {as you say}, it can leave finger oils on which causes issues when the heat up

[@yt225984]

I always find that the enclosures are a problem. Yours is neat. Where did you get it?

[@neutronstorm]

Hi Vincent, I got the enclosure at Jaycar - www.jaycar.com.au/metal-case-184-x-70-x-160mm/p/HB5446 . It seems to be fine. I should have actually measured it out instead of just guessing as I wanted to mount the panels in the sides rather then the top. These particular boxes are designed to have the goodies mounted on the soft metal of the sides rather then the thick metal of the top part. It was hard work cutting through the top to make the holes for the displays. In the end, it's actually worked out well having the displays on the top!

[@yt225984]

Great, thank you for your full advice. Now I understand why you placed the display panels in the top. Actually, they look neat very and good colour match from what I can see, I will go to Jaycar and get one of these. Thanks for your help.

[@rdtech9153]

+Vincent Hart about the case, recently , we will publish ..

[@robertlewis3772]

Hi, that was one of the best videos I have seen for thoroughness and consistency of presentation. I found it very helpful, thank you.

[@neutronstorm]

Thanks very much for the comment. Hopefully I will find some time soon to make another one as this one seems to have been fairly well received.

[@bearinitial]

Thank you! You tested everything I had a question about. Great video

[@neutronstorm]

Thanks for the comment and the encouragement Benni!

[@kirkchamberlain8490]

Just pick mine up yesterday and having trouble fine tuning the V & A. I’m powering it with a 20v 5ah porter cable battery,Output to a MOT electromagnet. I’m not able to get the volts to go past 6v while the amps stops at 8-9a. Seems like no matter what I do I can’t get the volts higher and amps lower. The magnet works great on a 12v car battery. What am I missing here?

[@neutronstorm]

The maximum voltage setting will be a couple of volts below the input voltage. The current should be variable from 0 all the way to 15 amps. Are you unable to set the current lower or is it showing a higher current than what you set?

[@kirkchamberlain8490]

@@neutronstorm I’m able to set the current where I like,it’s the volts that seem to be running lower than I’d like. If I set the current to say 6a,the volts will come up to 4. Would prefer the volts to run higher than the amps to avoid any heating up. I’m wondering if the electromagnet is the cause. I tested on a reg 12v car bulb and it works perfect. The volts adjust right where I want,same with amps.

[@neutronstorm]

@@kirkchamberlain8490 are you sure your not getting voltage drop due to a bad connection or poor quality wires? Is the battery upto spec?

[@neutronstorm]

@@kirkchamberlain8490 ohhh are you talking about the output volts? That's totally normal. The voltage will only rise up to what is needed to reach the set current value. So if your load is pulling 6 amps at 4 volts you work out it's resistance using the v = ir formula. R = v / i so r = 4 / 6 so the resistance of your magnet would be 2 thirds of an ohm. A light bulb will change its resistance as it heats up but a coil of copper wire not so much. To get to 8 volts you would need to double the current to 12 amps. Basically what you are seeing here is the device is keeping the voltage in check to stay within your set current limit.

[@neutronstorm]

@@kirkchamberlain8490 to have the voltage higher than the current you would need to increase the resistance of the magnet. If your built it yourself, add more wire, maybe double the amount.

[@lasersbee]

15:00 It is obviously not taking the X.00 to X.09 into consideration and locking anywhere between X.50 and X.59. It is only locking in 10mA/10mV increments.

[@neutronstorm]

Hi lasersbee, that's an interesting theory however from what I remember the other device works differently so I don't think if that is what's happening, it's happening that way by design. Also, the designer of the device has commented that it could be due to the current shunts being damaged. I will have another play with the device soon and see if your rounding theory is correct.

[@clastegenfeldt4751]

The problem with the set point for CC/CV indicates a firmware programming error, not an analog circuit one. From your video, without having such a module myself to test, it seems that the programmer just checks the FIRST decimal. So when you set say 1.00 Amps, it will go up to 1.09 since the first decimal is still zero for both the reading as well as the set point. The second decimal is NOT ROUNDED but simply TRUNCATED. This would be easy to fix in firmware, but otherwise you just need to be aware of it! Set your threshold 0.1 lower than desired and you will be 0.01 off instead of up to 0.09 off... (for 1.2 A set 1.10 or 1.19 A and it will detect it when it crosses over to 1.2 A). If someone could just test and see if it is any difference at all if you set 1.19 or 1.10 would be informative. If what I wrote at the start is correct it should matter at all.

[@vspri3813]

Clas Tegenfeldt t

[@drEmulatorMadmax]

i bought one of these units to power various things, only thing wrong is you have to use the output negative, i'e you can't use the same negative as the input on your items being powered as it affects the displays current/watts readings, other than that i'm happy with it

[@neutronstorm]

drEmulatorMadmax yes that is the case. The current sense is in the negative cable so all current must flow back through the negative cable of the device. If you try to run these in parallel or with some type of common ground then you will find that there are alternative paths for the negative return current that bypass the current measuring shunt and therefore cause false reading. This will cause the device to behave strangely.

[@robertb3595]

Does the little fan on the board come on when power on or when unit gets hot? I've got the same model and fan is not coming on when radiator is hot.

[@neutronstorm]

Robert B it seems to be speed controlled by the current? But yes mine does come on at some stage but it doesn't run all the time.

[@robertb3595]

Yes must be the current as it comes on at higher load. So it will keep going in freezing conditions too, lol

[@neutronstorm]

I assume that they don't need to add a temperature sensor if they just spin up the fan based on a load calculation. Probably saves a dollar.

[@theoriginalAudioDome]

i was wondering if i was using only 12 volt for my purpose ,can i use more current then 15 amps?

[@neutronstorm]

No, you can't exceed 15 amps.

[@santiagoestevez623]

Hi good video I have order one for me Have u tried to use them in parallel? For dual power?

[@neutronstorm]

Hi Santiago, I haven't tried them in parallel as this is not recommended. I just had a closer look at the board and like many others, the current sense circuit is in the negative side of the circuit. This means that when you common up the supplies, the current from one supply can return back through the current sense of the other supply. This effectively gives false reading and you end up with one supply limiting it's current ( as it's seeing it's current plus the return current from the other PS ) and the other power supply getting driven to hard and above it's limit ( as it's not seeing it's current as it's getting returned via the other PS ). This typically doesn't work out well. In the best case your just going to have minimal or no current limiting and in the worse case the lack of effective current limiting is going to cause something to go pop. Proceed with caution. I am not sure why they don't put the current detection in the positive side of the circuit. It's probably easier to read the voltage drop over the current sense resistors when one side is grounded, ie. potential difference from ground. It could also be it's just easier to layout the board with the current sense in the negative line as the positive half of the circuit is already chock full of components.

[@f.d.6675]

@@neutronstorm whats about using a polarity protection to prevent that?

[@zokonjazokonja]

You should be able by adding forward diode on both of units (which is also recommended to use when you connecting battery on output), use schotky diodes, they have some smaller voltage drop (i.e. 0,5V), less heating.

[@TheKetsa]

The display is wrong by 0.1 amp, but maybe a multimeter would show spot-on output. No calibration possible ?

[@rdtech9153]

+TheKetsa about the error, I just talk about this it is error between setting value and display value. it is nomal. because there is alway error between real value and setting value （or display value ）, it is nomal . I saw your error is bigger, I guss it caused by PCB mechanical deformation from some pressure. and when something toch the sampling resistance (constantan wire), those can cause this error. there is a way to decrease this error, not delate. disconnect all things ( input power and load ), then keep pressing the SET key and then connect input power supply , until the LCD display lights, you can losse the button, then the calibartion is done so it decease this error so you can try

[@neutronstorm]

Hi TheKetsa, thanks for your comment. The issue wasn't that it was slightly different to my multimeter ( that's to be expected ). The issue was that it's not internally consistant. The unit switches from CV to CC mode at a voltage higher than it's set point and it actually show on it's own screen that it's switching at the wrong voltage! RD Tech seems to think this may be a fault on my one unit that could have been caused by damage to the sense circuits during transport. The device only uses a few calibrated wire links as sense resistors so any bending or warping could make slight changes in theory. The three current sense wires are very close to the side of the board and actually touch the side of the packing material in it's shipping box. Any impact to that side could potentially cause these wires to be knocked slightly out of calibration. I have received a new DPS5015 that I plan to use as a replacement for the one that's slightly out of calibration. I might make a video of how it was shipped and how this damage could happen.

[@InteraliaTony]

At 38 mins you mention the warning about "outputs" and "the module being burned". It could just be a warning not to connect your power supply (into the module) to the output terminals (out+ and out-).

[@neutronstorm]

Tony Fishpool thanks for the comment. My point was that a battery *is* a power supply so does that mean you can't connect a battery to the outputs? Does it mean you can't connect the battery *first* to the outputs before the input supply is connected? Does it mean that the outputs can't handle the full 60v of the input side? It could mean any of those or all of those. In testing it seems fine to connect a battery to the outputs so I can only assume that as long as the input is powered up it's OK to connect a battery.

[@neutronstorm]

Further to this comment, I have received a comment from RD Tech about the unit - "if input is 0V, but it can't be short circuit on input ,. the modle will show battery voltage. but I don't advice you do this , there is a risk to damaged it by some other wrong operatiion . when you use it , please try not to connect battery, it has some risk " To me this means that you can connect a battery to the output but it increases the risk of damage to the unit especially if the input is short circuited.

[@dlaurent67]

Hi. I know that the subject is old but what's the interest of even 2 modules in the same box? Thanks

[@neutronstorm]

Not really sure what you mean. This is just a video of me talking about something I made. I am not a professional KZbinr and I don't make content to be popular. People are free to watch if they like or just click though.

[@dlaurent67]

@@neutronstorm sorry for my english, I'm french. Perhaps my words were not good. I'm really interested by your video. I'm not a youtuber too. I've bought two of these modules and I was asking to myself if there is an interest to have two modules in the same box except it was your funny choice, the goal to have 2 power supply near of you. My message is really positiv. Best regards. Laurent

[@afroninjadeluxe]

Why didnt you just pick a more common 230V/110V fuse holder? Voltage has to do with creepage and insulation only, doesnt it?

[@neutronstorm]

Hi and thanks for the comment. This has been covered a few time already in the comments. Basically a DC currect is harder for a breaker to stop due to it no crossing through 0v periodically like AC does. Think of DC like a jacobs ladder, once the current starts, its difficult to stop. In a jacobs ladder, the air breaks down and a spark is formed. The heat and the existing spark create conditions where the air isn't a very good insulator and by increasing the distance between the contacts, it may cause the spark to get bigger, not extinguish. If the breaker's only method of stopping the current is to separate two contacts, it's possible that a small spark as they are separated can grow to a large spark bridging the gap. If this happens in a high current situation then a huge amount of heat is generated in the breaker and a fire starts. DC breakers have multiple methods of stopping a spark. They might shove something in the spark gap or they may have a magnet that pulls the spark apart or a combination of both. A common mistake is to use AC breakers in a DC solar system or battery system. In these system you really do need a DC breaker and you will often see they are double gang so they cut the positive and negative terminals simultainously. It's hard to get this feature in an AC breaker.

[@movax20h]

are output isolated from inputs? or is ground shared? It would useful to know, if you want to run two or more of these modules in series for higher voltage, or when powering up multiple things when you also need separate grounds / no common potential or loops.

[@neutronstorm]

Check toward the end of the video where I test exactly that. Buck converters do not have a transformer in the design so therefore can't be isolated. The negative line seems to be common with input and output.

[@BadMax02_VR]

@@neutronstorm can you write the timestamp because the video is so long

[@neutronstorm]

@@BadMax02_VR try from about 40:50

[@BadMax02_VR]

@@neutronstorm to bad but i have a lab bench supply with 300w like a whole unit and I can put this one with one of the modules in series because I have done that to charge a 48v lithium ebike battery to 52v

[@adm.tecnologo2242]

Can I use a 17 Volt 70 Amp Dc transformer or source rectified and filtered on this DPS5020?

[@neutronstorm]

adm. tecnologo yes that would be fine. You could only get about 15 volts out maximum as the output voltage will always be lower then the input (buck converter).

[@hooperwille]

What do you use this 40Ah li-ion battery for?

[@neutronstorm]

hooperwille thanks for the comment. I use the battery to run a portable fridge in my vehicle mainly. Its charastics are very similar to a typical lead acid car battery however it has some advantages and differences. It is a slightly higher voltage than a car battery at about 13 to 14v where as a car battery is typically in the 11 to 13v range. The lifepo4 battery is generally more durable in some sense as it can tolerate the total discharge of all of its rated capacity without damage. Normal car batteries do not like total discharge and degrade if this happens. The lifepo4 batteries don't like being run outside of the 11 to 14v range so you do have to take care when using them or have a separate battery management system to look after them. I just do it manually. My fridge has a low voltage cut off which I set to its maximum voltage and this is sufficient for me. You also need a more complex charging system to charge and maintain the battery. The lifepo4 batteries are fairly durable so they can be charged from just a constant voltage source like a car alternator but I take mine out and charge it on a proper charger periodically. The real charger can also charge it to its maximum capacity safely so I often do that just before a bit trip. The battery runs the fridge for about 4 days if the weather is mild and the fridge is stored in a cool place. Less if it's left in the hot vehicle in the middle of summer or if you use it to cool something rather then just to maintain its existing temperature. If anybody is interested I could possibly do a video on this setup.

[@TheDGITA]

@neutronstorm Do you think that 60V 20A is it enough to power up one of this device? I will use 2 smps 60v in parallel :)

[@neutronstorm]

It will certainly power it up! Just be careful as the 60v is the maximum so you should make sure your supply doesn't drift above the 60v. Also, check to make sure your power supplies are ok to be run in parallel, some are, some aren't.

[@Stefan_Van_pellicom]

How is there a difference between AC and DC fuses ?

[@vaclavtrpisovsky]

I don't think there is, you can for example use a 250V AC fuse in a Li-Ion battery circuit to protect from shorts. However, since it is made to withstand hundreds of volts when blown, the fusible wire will be longer than necessary, with higher resistance (causing more losses) than a 48V DC car fuse for the same current rating.

[@GermanMythbuster]

DC Fuses are designed differently! Reason: AC crosses 0V and therefore arcs extinguish way easier than DC arcs! Same reason why switches have different current and voltage ratings for AC and DC.

[@davecc0000]

What are the dimensions for the cutout to install a module?

[@davecc0000]

Ah. 71x39 mm.

[@3D_Printing]

I think a separate Volts knob and separate Amps Knob would be nice and a bigger set display

[@neutronstorm]

Hi PBSO3DP, I didn't make the electronics, only put it in the enclosure. The video was about how I used the DPS5015 modules to make a device that is similar to a bench power supply. A real supply would be good having more analogue controls. One interesting point I didn't mention in the video is that the knob is a rotary encoder so it does give nice precice changes to the set points.

[@3D_Printing]

Yes I know the builders could improve it this way

[@3D_Printing]

I like this video and this unit and you give a great look at this device which is useful IMHO. I am Very Old School so would like analogue meters to see varying current and two Knobs volts and Amps

[@ninguno1756]

Hi. Great totorial. Thank you. Do you know if is posibily made a Diy Dual PSU? Like two modules, two atx psu. ungrounded and serial connection between to take zero and + voltages and - minus voltages. Regards

[@neutronstorm]

ninguno if you used isolated power supplies I can't see any reason why you couldn't then connect the outputs of multiple devices together in series. ATX supplies aren't isolated by design so you will need to modify them to do this. Be aware of any safety issues when doing this.

[@BadMax02_VR]

@@neutronstorm i actually did that with 5 400w server power supllies i left the first one grounded but the other ones are isolated to keep the voltage from floating up to high in reference to everything else and got a nice 60v 32a powersupllie with im going to use to power 2 dps5020 modules one of them limited to 15 because of loses and using a bit more than 2000w when on full load but i think that i will never bu using 2000w in parallel or so

[@shaileshparikh9913]

Sir can we use this for electro plating rectifier?

[@neutronstorm]

It's not a rectifier but it would be suitable to regulate a high voltage dc supply down to an acceptable voltage and current for electro plating. Keep in mind the supply voltage must be DC and a higher voltage than you need. Current limit is 15 amps.

[@shaileshparikh9913]

@@neutronstorm sir thanks for your reply as you suggest me it can nor work for electro plating . Sir I can used this as keeping current 15 amps and voltage is maximum 6 volt. For 1 minute .

[@neutronstorm]

@@shaileshparikh9913 it should do that.

[@jamesandonian7829]

its says its a step down voltage regulator, does that mean the output voltage wont exceed the input voltage? so if I want a maximum of 50v, must I input 50v???

[@neutronstorm]

James Andonian this is a buck converter so it only goes down. You need to input a higher voltage then the maximum you expect to get out. From memory, 60v in gives you 50v out which is the maximum for the device. If you want to boost the input voltage you will need a boost converter. Boost converters can only output a higher voltage then the input. If you want the best of both worlds, you need a boost buck converter. It's basically a boost converter followed but a buck converter in series. The boost converter outputs a high enough voltage so that the buck converter will be able to regulate it down to what you need. In my case, I had an existing 48v power supply so a buck converter suited me fine. I can get any voltage upto about 40v.

[@elecdroid3666]

Hi. Can the product Limit the current while under the load?

[@andrescirulnick2307]

Si

[@axelkoppen3037]

can you also use it for step up? input 12v output 26v?

[@neutronstorm]

Not with this module as it's a buck converter (down only). This is why I feed it with a 48v supply so I can access any voltage less then that. There is also a boost-buck converter from the same maker and it can step voltage up or down.

[@caroman6761]

where did you bought the connectors please?

[@neutronstorm]

Which connectors are you talking about? I bought most of the gear from Jaycar or from eBay.

[@vinatechcoy]

Charging the battery was not the intended design of the module. I myself is an analog electrical design engineer. To verify whether or not the units meet the specs. Use a resistive dummy load instead. As the nature of CV/CC switching over automatically. A high capacitance load is not recommended. Without a DC blocking diode, using a battery as a load. As soon as the battery internal voltage reaches the Vset, then oh god ! It's the design engineer's nightmare. Just imagine the LM317 with a huge capacitor at the output then you short the input. Without a protection diode (to bridge between input and output) to provide a low impedance discharge path. The capacitor will discharge into the output of the regulator. The LM317 is prone to fail.

[@neutronstorm]

Hi Hoa, thanks very much for your comment. It's great we are blessed with the knowledge of an analog electrical design engineer. Charging a battery is an intended application of this device and it does include a protection diode in the circuit. Please watch the video and read the commends for more details. I used a light bulb to test the device initially and then used a battery to test it at full current. When the device is being operated at a constant current, there is no difference between a capacitive load and a resistive load. These characteristics are only important when there is a change in current.

[@xenofonlive]

Hi.Can i use a solar panel? 24v 200w ,max voltage 44.27v ?can handle changing input voltage? but constant output?

[@neutronstorm]

Hi Xenos Anomos, this isn't what it was designed to do however it may work. I think more likely what will happen is that the device will keep trying to draw more and more power to transfer the maximum amount of power to the battery and the voltage at the input will drop. At this point the device will either self limit or it will cutout. I am not sure. If I get some time I will try and test it.

[@xenofonlive]

ok. if you try it let me know. thank you.

[@neutronstorm]

Have a look at this video kzbin.info/www/bejne/g6Caip6mgbutf9U which shows powering a buck converted directly from a solar panel. It does work however it's not going to be optimal. The correct way to do this is have a solar charge controler charging a battery and that battery powers the load.

[@xenofonlive]

thanks

[@xenofonlive]

i do not want to use it for charge battery but as a power supply for my lipo charger!

[@tadeasgrohmann8392]

it will work with 24v(max is 27v) 10a switching power supply or will be better to use transformer with rectifier?

[@neutronstorm]

Tadeáš Grohmann. It will work fine with the switching power supply. It will only output voltage lower then the supply voltage so your maximum output voltage will be 22v or there abouts.

[@tadeasgrohmann8392]

+neutronstorm so if i will use 50v 10a transformer (with rectifier and filter ) it will give me full power

[@neutronstorm]

Read the specs. Full power is 50v and 15a output. Input. Would.need to be 55v ( tightly regulated ) with around 15 amp available. I would get a 20amp or higher supply so you didn't get any voltage drop. You would also need to have it deliver 55v exactly to the module and adjust for voltage drop in the cables. Ie. Have sense wires from the regulator. In theory, this should give you the maximum 50v 15a at the output. In practice it's not a good idea to run this sort of equipment at its maximum power without your own testing to see if the device can meet its specifications. You would need to access heat output, cooling and duty cycle if you planned to run this device hard. Let us know how it works out. .

[@tadeasgrohmann8392]

+neutronstorm so i want to get full power i mist use 55v 15-20a transformer with some protection and some big cabels

[@neutronstorm]

That's what the specs say. Good luck with that and be careful.

[@MrBrymstond]

Chances are the inductor on the left has issues, I would even bet on it.

[@gerardtonno9458]

neutronstorm, if you are not already aware of it, I can tell you how to fix the display on that Fluke 87 so that all the digit segments are nice and bright. It's actually a very easy and quick fix. If you are interested PM me.

[@neutronstorm]

I had it apart yesterday as a matter of fact. I assume it's just a matter of cleaning the contacts between the screen and the pcb? I think I may have done it once in the past but I might not have done a great job if it's gone bad again. Then again, it's probably 25 years old.

[@jeremy_6838]

You should use "Hold Peak" on your Amp clamp

[@inspectormore-anonymous1259]

amazing work man, really, great work

[@neutronstorm]

Thanks for the encouragement

[@rdtech9153]

+Inspector More-Anonymous yes, he is a industrious and serious man,.I like his work and channel

[@rdtech9153]

+neutronstorm you are welcome

[@inspectormore-anonymous1259]

RD great job creating these awesome products, I look forward to ordering your new buck boost unit, any idea when you will have a higher current model available?

[@rdtech9153]

+Inspector More-Anonymous Hi friend thank you for your support. now there is no higher current version. sorry

[@sirlespatterson7380]

Can this be stretched to 55V output?

[@neutronstorm]

Don't think so. I think it's software limited and even if you could it would exceed the voltage of the capacitors. Also note that this is a buck converter so the input voltage must always be higher then the output so to supply 55v you would need 60+volt input.

[@MCsCreations]

Looks REALLY nice! But it's a bit expansive. I thing I'm going to go with a DPS 3003. :)

[@nielsdaemen]

What about the ripple on the output?

[@neutronstorm]

Hi Niels, I didn't measure the rippler on the output as I don't have an oscilloscope. I guess I could have used my multimeter on AC mode. In any case, I would imagine it would be quite high compared to a traditional lap power supply as it's based on a DC to DC converter which works but pulsing energy through the coil into the output caps. Check out RD Tech's channel as he has some videos showing ripple on some of his devices. For my usage which is charging batteries and powering misc devices it's not an issue. If your usage is to power delicate circuits without filtering then you should test this as it may not be ideal.

[@neutronstorm]

Also, check out kzbin.info/www/bejne/jaHFnKuCZdVqq5o . Seems this guy has done the testing you were looking for.

[@yick39]

neutronstorm

[@irgski]

750W? out of that small, ambient air cooled unit? Find that hard to believe. Also, you should be taking your voltage measurements at the load....pretty sure that you are getting a voltage drop in the leads going to the battery.

[@neutronstorm]

Hi irgski, thanks for the comment. DC/DC converters are really coming along and you can get some amazing results from these units so you see in this video. I was surprised by the efficiency myself but as you can see in my test, it does perform that well and it capable of supplying it's rated 15 amps with no problem at all. With respect to the testing method - It would be incorrect to measure the voltage at the battery as you want to take voltage measurements as close as possible to the device under test. In this case, I was testing the power supply not the battery so the correct place to take the measurements is at the power supply. The wires in this case are just part of the load and it wouldn't matter if they did have a massive voltage drop as the wire/battery system as a whole would still have been dissipating that much power. That being said, my tests were very rough and were only meant to give a ball park figure of the efficiency of the device. To do complete testing I would need to have better current measurements and log the results through many combinations of input and output voltage. This video was just a record of me doing my own experiments with the device to satisfy my own curiosity.

[@GliCidO]

Great build... I would swap the fuses inside so the right output stay linked to the right fuse... :) just an idea :)

[@neutronstorm]

Thanks for the idea. Someone else pointer that out as well.

[@tadeasgrohmann8392]

what heppends when i will power 1 dps5015 with 24v 10a power supply

[@neutronstorm]

Tadeáš Grohmann. Should be no problem. Maximum output will be 10% lower then input.

[@tadeasgrohmann8392]

+neutronstorm so the output will be 45v and 13,5a its it true or not

[@neutronstorm]

The exact maths is output must be 10% higher then the input if I remember correctly. There will be a power inefficiency so you need to supply more power (in watts) then is being outputed. Some will be lost as heat in the conversion. This device is relatively efficient so I would allow for 5% power loss. It may be higher at extreme conditions. To get maximum output, I would go for a tightly regulated 55v input. Do not allow the input supply to exceed 55v at any time or it will blow. This is really close to the maximum voltage of the input capacitors on the Dps5015. Assuming your power supply can keep the input at 55v, you should be able to get 50v output at 15a.

[@the22fu]

Can someone tell me how to run this in constant current mode? Mine always runs in constant voltage mode which is quiete annoying since the power supply is sometimes not abled to detect a high ampere load. For example I have a 100W hand vacuum cleaner for my bench and without the CC mode I only get the 100W out of it when I double the input voltage from 12 to 24 volts. It is originally designed for cars. Normally it uses 8,3 amps but in cv mode it just uses about 2,4 amps to about 4,2 amps. Besides that it is a really awesome bench power supply!

[@neutronstorm]

Hi Infestus92, A Constant Current (CC) and a Constant Voltage (CV) supply like this one will limit so that neither the voltage or the current will go above the set points. The power supply will keep increasing the voltage at the output until it reaches either the maximum voltage (CV) or the maximum current (CC). In your case, you have what is likely a resistive load which means that as you increase the voltage applied ( think pressure ) the current ( flow ) will increase as well. In your vacuum cleaner example, you likely have the maximum voltage set to 12v and when you switch on the device, a current will flow through the motor. This current limited by the specific configuration of the motor as long as it doesn't exceed the current limit you have set on the supply. If you wanted to see the supply operate in CC mode, you would need to reduce the CC limit to something lower then the cleaner would like to consume. For example, if you set the supply to limit at 1amp and you then switched on the cleaner, you would see the supply go into constant current mode of 1amp and the voltage would likely show something like 3 volts instead of 12v and the cleaner would likely sound really sick. In this case, the supply has raised the voltage up until the CC limit has been reached. Switching off the load of the cleaner would allow the current to drop and the supply would push the voltage backup to 12v and you would be back to CV mode. The other option would be to set the current back to 8 amps and set the voltage to something much higher, try 14.4v or higher. This will allow the power supply the voltage to push the current up to the 8 amp limit. Please note that this will likely drive the device over it's rated 100watts and it will probably let out the smoke. 14.4v is the voltage that a running car will see on its electrical system so should be still ok. Why don't you try it at 14.4v and 7 amps limit and see if that gets you close to the 100 watt rating of the device. Hope you don't burn out the vacuum cleaner! Good luck.

[@hrshovon]

I set input voltage to about 5.10V and got about 5.04V on my multimeter with no load. Then I set the voltage to about 40.12V and got 39.5V output. (I have 4 ATX PSUs in series and they seem to be running just fine and both tests are for no load). Is this almost half a volt deviation at higher voltage normal? This power supply is really nice by the way. My multimeter could be faulty. So I am just asking if someone encountered the same issue.

[@neutronstorm]

I haven't noticed any major deviation from my multimeter. I guess you should check with another multimeter and see how that goes.

[@hrshovon]

I think so too.I have a INA219 based power monitor which sortof agrees with the reading on this PSU panel. Guess I need to check it using a Fluke or something.

[@reptiloidx8942]

HELLO THERE CAN SOME ONE TELL ME WHAT IS THE MAXIMUM INPUT CURRENT FOR THIS DEVICE ??? THANK YOU

[@neutronstorm]

Арxитектор Вселенной the devices is a buck converter which always output a voltage lower the the input at a higher current. The maximum output current is 15 amps. Since the input current will always be less then the output current, I would say that you could use 15 amps as a maximum input current during normal operation. There would likely be a higher in rush current when first connected.

[@reptiloidx8942]

Oh yess . Well its all cleared out like dead drunken scary dream about pink pony .......... nO I NEED A GOOD POWER SUPPLY OF MAYBE 24V 20A .......................

[@neutronstorm]

Арxитектор Вселенной sorry just edited my reply. Should have been 15 amp maximum not 20.

[@reptiloidx8942]

OH OK WELL LUCKY ME I GUESS MY ONLY CHOICE TO GET IT FAST FROM ENGLAND IS 24V 15A .........

[@reptiloidx8942]

HELLO THERE AGAIN . WELL WHAT IF I WILL USE 17-19AMPS INPUT CURRENT HOW WILL IT WORK THEN ???

[@egor4028]

The other day I assembled the unit as the source was used. DC48V-12.5A bought on ALLe worked 5min tozhe burned DPS5015. I tuned 9V 0.5Am, protection 9V at 0.8Am failed to connect the screen. BP (DC48V-12.5A) went into the defense. The power supply is not burnt. The input is not closed, and the output is full. The plus (+) of the input is called with all output terminals (+) and (-) DO NOT BUY

[@neutronstorm]

Sorry to hear you had some bad luck with your DPS5015. Hopefully you will get a new unit from your supplier. I haven't had any problems yet with mine so I hope that yours was just a one off bad unit.

[@egor4028]

Manufacturer response(ответ производителя) ...It is the problem of broken MOS under heatsink, is it possible that you try to repair it ? If it is, how about we give you 250 BG points for compensation? If it can not be repaired, how about we send you MOS part? Looking forward to reply....

[@JasonWW2000]

Sorry, but that is Banggood (seller) response. The manufacturer is RD Tech. When dealing with Banggood you have to keep annoying them and demand it be replaced.

[@JasonWW2000]

I bought directly from RD Tech from their AliExpress store. They have much better customer service.

[@jamesandonian7829]

I bought this thing for $13, I hope it works half as well as it claims. my power supply outputs 24v at 10a so 240w. I need 48v at 3a so 150w. fingers crossed

[@neutronstorm]

James Andonian sorry it's not going to do that for you. You need to buy a boost converter or the boost/buck converter that was recently released.

[@jamesandonian7829]

neutronstorm ty, yeah its a regulator not a converter. how does it regulate the output? does it use dissipation? that would really suck

[@neutronstorm]

James Andonian it uses a coil that it switches on and off to control the charge. Google buck converter circuit for more details. It is quite efficient. Does not burn the excess off like a voltage regulator. Typically 90% effeciency but in my testing it was more efficient then that. It depends on the input and output voltage and current.

[@ronniezzzz]

is it a truck lamp

[@neutronstorm]

No. The lamp I use is a standard car headlight. The light has 2 fillaments internally, one for the low beam and the other for the high beam. They have a common "ground" terminal in the middle. In a car, each would be powered by between 13 and 14v from the cars electrical system and they are wired in parallel. In practice I believe that only one fillament is powered at a time. In my testing, I connected the power supply to the positive terminal of each fillament leaving the negative/ground terminal disconnected. In this arrangement, the 2 fillaments are powered in series so I need double the voltage (28v) to light them fully. From memory, one fillament was rated 55w and the other 60w. Obviously in a car electrical system there is a fair bit of variation so I was happy running the "system" at 160w. Being youtube, I probably should have tested the bulb to destruction however I never expected anybody to watch the video so I didn't blow up any of my equipment. I did manage to burn the top of the table. 160w is a lot of heat.

[@nielsdaemen]

9:52 You mean 48.8 V

[@neutronstorm]

Yes I make lots of errors reading out numbers in the video. I corrected the ones I found. For some reason my brain has problems reading numbers out aloud. When I am speaking it sounds just fine for me until I play it back!

[@BellyUpFishGarage]

Boy, good thing you caught that... Disaster was narrowly avoided........

[@srqdriftmike]

Awesome video, thanks!

[@neutronstorm]

Thanks for the comment and the encouragement srqdriftmike! I am glad you liked it.

[@ronniezzzz]

are you sure more than 14 volts

[@neutronstorm]

I am not sure what you mean by this. Yes the power supply can go over 14v. Yes I am sure the bulb can handle double the 14v as I have connected the fillaments in series so they will take 28v. In any case, the bulb is rated to 55w+60w so I should be able to use it at this wattage without issue. Running it over the rated power would likely shorten the life of the bulb. Also, I don't have the bulb in an enclosure that acts as a heat sink so that would also affect it's longevity. In any case, I only use this bulb for load testing, not in my vehicle so I don't mind if it's life is shortened.

[@ronniezzzz]

a really nice setup

[@pollydor07]

Thanks

[@inspectormore-anonymous1259]

Im building something that is quite interesting, tomorrow I will message you and possibly you could help me if you have the time

[@AIexanderHartdegen]

What the hell why this video is so long??

[@PowerOn-]

I've done a review for the housing for this power supply: kzbin.info/www/bejne/rn_blquOeKxonqc

[@bulwinkle]

How disappointing! Nothing went bang.😣

[@neutronstorm]

Sorry Robert, I honestly didn't think anybody would watch the video so I didn't destroy anything. Maybe next time.

[@whollymindless]

This is neuronstorm, not electroboom....

[@lexb]

Лень смотреть, он раскочегарил его до 750 ватт или нет?

[@neutronstorm]

The unit tested OK at 15amps. The current is what stresses the device no matter what the voltage. There is the same voltage drop and about the same heat generated at all voltages. I am confident the device would hold up at the full voltage and current although I don't have the gear to test it at that power level.

[@raymondj8768]

aaaaaaa aummmm aaaaaaaaa sorry got to go this vid couldof been 15 min if you take out the aaaaaas

[@АлексейОжогов-я2м]

горят эти 5015, вот ссылка на ремонт kzbin.info/www/bejne/i6rQaJl6rqykgdE

[@drEmulatorMadmax]

@ 3:28 oh the humanity of it you should be banned from you tube for life for that lol only joking, looks ok to me (you should see some of my wiring) i'm thinking of getting one of these waiting for a sale and hoping i don't get lumbered with a reject

[@neutronstorm]

Anything looks ok after it's covered by heat shrink. Underneath is a heap of heavy gague wires platted together and then an attempt to get some solder on it without menting all the insulation on the rest. I probably should have used some terminal blocks or something.