Matrix PSU Unboxings & Teardown
ฝัง
- เผยแพร่เมื่อ 30 เม.ย. 2024
- Originally released as an exclusive video for Patron supporters.
A single take unboxing and teardown of two Matrix Bench Power Supplies:
MPS-100C and 3CH MPS-3264
www.szmatrix.com/products/mps...
www.szmatrix.com/products/mps...
No editing, straight from camera.
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#ElectronicsCreators #Matrix #powersupply - วิทยาศาสตร์และเทคโนโลยี
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I like:
- Coloured front panel, who thought the original design was a good idea?
- Insulated banana jacks, I've standardized on that for everything new I buy as it lets me buy probes and adapters that I can use with both my DMM, PSU, load and other custom jigs. I just have an extension cable with spring loaded retractable shields for when I want to connect any of my insulated cables to something with binding posts. I also never connect bare wires to binding posts because either the design has a standard port like USB and I have an adapter for that or the cables are too short anyway to reach the PSU, so I just have some cables with mini-grabbers and connect to the wires or directly to the DUT.
- Press knob to change digit, I've used quite a few PSUs with this and rather like it, always 'just works', much better than the very hit or miss of knobs with wonky acceleration, but dedicated left/right arrow keys for digit position is my favorite.
- Watts display, I never enjoy having to do that math in my head while holding the DUT together with two hands and probing with my shoulder before I realize it's drawing 100 W and explodes.
- Variable fan control, both for reduced noise, but also because I now have an instinctive muscle memory to rip out banana plugs when I hear fans ramp to 100% (has saved some DUTs)
- Second one already has nearly EEVBlog blue membrane keys
- Wiring looming with ties, love to see that, many low cost PSUs are just a rat's nest inside of cables waiting to rub on sharp heatsinks.
- PCBs are clean, no big flux residue stains and look to be of good quality, even ENIG!
- Adjustable display brightness and beep disable, great when using at home or in an office with others.
- Internal series/parallel relays with good UI, too many low cost power supplies advertise series/parallel operation but it's fully manual.
- Isolated serial port (although not sure it would be worth stocking for a PSU of this price point)
- Relatively small output capacitor on the linear one so good for testing sensitive stuff eg. LEDs, lots of them just slap a big cap on the output to get the noise spec down.
- Inrush NTC on the SMPS one, kinda wish my linear PSU had something to take the edge off the inrush.
- It boots quick and isn't too smart for it's own good.
- Has a serial number and it appears to include the date of manufacture, so if worst comes to worst and everything hits the fan you can recall only the affected units.
- The specs (assuming it meets them of course)
- MELF diodes ;)
I don't like:
- Knob in the middle of the keypad, they tried to be cool with the design like the Rigol PSUs and circular numpad but it just makes switching between PSUs a pain. Few PSUs get this right.
- None of the components I could see have any sort of compliance marking, don't forget the power supply enclosure itself is class I but the output is class II and needs to be double insulated.
- No QC labels or stamps on the outside or inside, particularly no "Hi-POT OK" mark on the unit or transformer. They should and could be doing it but you never know. (imo that dented capacitor should have failed QC)
- Only what I assume is a self assessed CE mark, I assume they can supply a certificate of conformity for what they actually tested to. But this is a mains connected device so there might be the requirement for the RCM mark to be obtained.
- Paint has not been masked off where the top case contacts the grounded bottom case so the device would likely not pass the 25 A ground bond test.
- No padding for the toroidal transformer (could be there, but can't see it), without one it's easier for the line worker to over tighten and damage the transformer or to be damaged in the field.
- I agree the ON, CV, CC indicator LEDs should be brighter but also would benefit from some diffusion to improve viewing angles and better feel of construction.
- That label on the front panel should have on it the maximum voltage permitted between the isolated output and ground (eg. "250 V PEAK").
- The input spec of AC 220V +/- 10% is not compatible with Australia's 240 V +10%/-6%. Particularly the linear one, it might be designed with enough head room, but should be tested and the spec changed.
- No obvious ESD protection between the isolated output and ground (couldn't see the PCB that well, there might be some)
- Mains input cables loomed together with the LV DC output cables using the same red/black colour code, mostly just a personal gripe, it's technically double 300 V insulated so nothing wrong with it.
- Lacks a label on the rear with all the input power specs and fuse rating along with country of manufacture.
- Font used to label the rear ports is the default condensed Times New Romanish font, because it's the default font for a lot of Chinese printing machines I associate it with cheap hastily produced items.
- Mismatched industrial design of the two units, is Matrix the ODM/OEM for both units? Seems strange one has binding posts while other has insulated? Or is the binding post one just an older design?
- Yellow adhesive used on some of the connectors looks like it could be the horrible stuff that turns conductive with heat and humidity (eg. Australian climate), could result in some warranty returns although typically that only happens when it's on the PCB and outside the typical 12 mth warranty window.
- Those two bodge resistors and of course the TO-220 "Flappin' around in the breeze"
- Isn't the µSupply! :P
*Possible deal breaking red flags*
- Large DC bulk capacitors with dents in them, particularly ones with large dents but no scuffs on the heatshrink label (like that one), are often dirt cheap used capacitors that have been salvaged from scrap e-waste in third world slums! Strongly recommend cutting the label off to inspect it, if you can see pliers bite marks they'd better have a really good excuse, you don't want a product from a manufacturer that uses salvaged e-waste components.
- The shot was out of focus of the main pass transistor, but the legs appears to exhibit 'solder pillows' which can be an indicator it's a salvaged part, but some TO-247 devices do come like that from factory, you'd have to determine the manufacturer and find out if that's how they come.
(considering the rest of the build quality I assume it's just a one off defect that got through QC on a Friday afternoon)
Summarized thoughts:
It looks pretty good for an entry level PSU but there are some things you should certainly investigate or change before moving forward. I would have happily bought this for $200-$300 off Aliexpress unbranded but only if I was still a university student, unfortunately those days I have high standards so probably wouldn't consider it, but I'm sure a large portion of your audience, particularly those who this would be their first PSU would buy it and enjoy it without issue.
Linear supply easy to retrofit a NTC inrush limiter, and yes I agree with what you say. But voltage range worldwide is now 230VAC, the Aus 240 is exactly the same as the tolerances just were adjusted to make no equipment change needed.
sadly enough no ethernet tho which is some what of a deal breaker for me , also don't know if it's full SCPI complaint
In the first one the fan grill is too restrictive, that's going to provide most of the air noise coming from the fan.
spring loaded retractable shields is such a nice way to start migrating towards all shielded!
Did you see the typo on the box; "Progammable"! The dented cap and bodge resistors with no sleeving on them ended my interest in buying one of these.
Make sure there's the schematics, bom and principle of operations in the manual. So its repairable like old school stuff was!
And the binaries if you need to blow the chip
For post-less terminals like this, Wago do some nice 4mm plugs with spring-connect terminals
Wago part no.s 215-311 & 215-212 for black & red respectively
And the earth connection ought to be green on the first one, not yellow.
Although green is the most common color for ground (especially in the US). Yellow is also used to indicate ground.
Here in Oz earth is green with yellow stripes. Possibly the other way around if you like pointless arguments..
@@j.f.christ8421 Yellow with green or green with yellow.Sigh,..Still, good sense of absurd humour is i a plus in my book :-).
Absolutely there should be proper binding posts with through holes, safety skirts and molded on color. It doesn’t cost _that_ much more to make it proper. Also the spacing between terminals should be 0.75 inches (1.9 cm).
I don’t understand companies not doing extra QA before shipping review units
Maybe they did extra QA.
@@Okurka. That would be worrying because of that dented cap and the ill-fitting enclosure on the double channel device.
China doesn't do QA. The customer is the QA - if something is faulty they just give you another one. It's cheaper than paying people to sit at benches doing QA.
@@sw6188 yes of course not - but this is not a normal customer - if you sent out review units you better doublecheck
@@Okurka.that wire touting looks like it
For a moment, I thought someone had boxed the Apollo guidance computer and I'll see a 1202 error.
I wish they both had keypads. So much faster to just type in a value than messing with adjusting-scrolling-adjusting-scrolling-adjusting.
You're right on the color. Stock it's just gray.
The processor on the back of the front panel is a display multiplexer.
First one:
Brief torture test you did gives me lots of confidence - I've seen videos from you with much more expensive kit failing those tests.
Build quality seems OK (bodge resistors aside). Screen is nice and bright. I like the insulated banana jacks. I can re-use alligator leads from my meters with them.
I'm in the US, so I'd need a 110V version. But for a couple hundred bucks? Seems like a good deal, and I'd buy one from you.
Second one:
There are heaps of medium-power triple channel supplies on the used market. This one does not spark joy in comparison to those.
Spade connectors and JSTs self-latch -no reason to glue them
Yeah, locking spade connectors are an absolute pita to remove, adding glue is just annoying.
If the price were right I'd consider the 3-output PSU, but I'd still be tempted to save my change for another month and go with a Siglent or Rigol.
The last minute change resistors daring to touch the case, small heat sink, dented capacitor and bringing mains to the front panel don’t give me a lot of confidence in the Matrix linear supply.
Chinese manufacturers seem not to mind, but I would prefer not to have mains wiring in the vicinity of the front panel. It is better to live with the switch on the back or use a plastic rod to communicate the motion from the front to a physical switch mounted on the power inlet conditioning board mounted at the back.
Just curious as to why. If it’s a plastic front panel and switch, isolated from the low voltage circuit, is it really a safety problem?
@@bobert4522 It is a case of best practices to maintain as much separation between the mains supply wiring and any small signal or output terminals to prevent inductively coupling radio frequency radio frequency noise on the mains wires. The second reason is physical separation to avoid arcing to the output terminals due to a fault voltage on the mains. If you look at the oscilloscope tear-down videos, note the power supply is in the back behind the bulkhead which holds the main processor board. The front panel switch is on the low voltage side of the power supply. The physical power switch is on or near the mains cord IEC connector on the back panel.
On a bench power supply with a one millivolt adjustability, there needs to be almost as much attention to noise mitigation as there would be for a scope or meter. The output will be a mess if RF is allowed to get into the voltage regulator.
I had seen too many power supplies in my life. Somehow I think we are heading backwards. You got them scopes, put some loads onto them and rapport the rf noise.
@5:00 Famou last words: "Its set to 240 Volts" 🤣
Even if it will turn out that it not the one, I will be very happy to get an eevblog power supply for my new lab. Always a pleasure, thanks Dave !
Thanks for the review. Looking forward to the ripple review. Would purchase in a moment on Dave's suggestion. Except, need a confirmation on the spacing between the banana jacks, colored jacks, a downloadable manual w/ SCIPI commands, and SCPI test. I already see it available on Amazon. - JQ
While I do have a fondness for high-power bench supplies, all I really want is a 3A bench version of the uSupply. There are inexpensive single-port 65W GAN USB-C chargers (e.g., Anker 715) that provide 3A at each voltage (5.0V/9.0V/15.0V/20.0V) which should be fine to feed directly to a linear output section with current limiting. Not as portable as the uSupply, but it would be just as versatile and do a far better job meeting my actual testbench supply needs. Most of my (rare) higher-power needs are met by my collection of laptop power bricks.
I have a 3A capable portable supply I'll be reviewing shortly.
The main difference between a charger and a power supply is reduced requirements for the stabilization coefficient and output current ripple for chargers. This may not be acceptable for many devices.
@@EEVblog2 Something like a miniware psu, but a little bigger would be awesome. 2 encoders (V/A) and and output on/off.
Would guess that manual was ring bound as they were still doing updates on it, so instead of springing for a print run of 2000 copies, and toss around 1900 of them every iteration of the manual, as they found translate errors and did firmware changes, these units came with a simple laser printed manual that got bound, as the easybind is very cost effective under 500 copies compared to a full print job.
Kind of a tough price point when I can get a better Siglent off Amazon free shipping for a little more. The lack of binding posts indicate amateur unit.
I've seen Beryl caps a lot, they are ever present in chinese LED drivers and various switch mode jobies.
I'd be worried about the quality when they misspell "ProgRammable" on the box.....
It's more than "gammable", it's "progammable".
1st one psu:
needs a quieter fan & a larger heatsink. and better assembly QC (filter cap). and front panel connectors didn't give confidence.
i didn't check if there was anything else than mains switch before transformer. if there is, then two pole mains switch is needed.
Nice video, thanks :)
Hi Dave, nice video!
I have the Nankafd 30V 10A single supply + USB and the menu / Firmware looks identical even the system menu. It’s also very well build inside for the price.
Noticed there was a Serial interface? Is there a USB controller interface then?
Looking forward to a detailed tear down and see how accurate the meters are, load performance and noise.
Would definitely prefer binding posts.
Yeah, a PSU should take any random cable you throw at it. You just don't always have time to bother with banana plugs... let alone safety ones.
So would I. It surprised me to see those sockets - so much so that I started looking at ways to mount binding posts through those banana sockets.
@@brumbymgBinding Post would definately be preferable, more versatile.
Can always include a converter.
@@EEVblog2 Best method, a converter with shroud, and a hole to allow a wire through, with a large knurled nut to fasten it.
Depends on what price you can sell them for, but I think you'll find it difficult to compete against Rigol or Siglent.
MPS 100C: Not so nice to strip the high side (mains) cable together with the low side!
For $200 the single output one is decent value. I think close competitor would be Siglent SPD1305x ($285). For 85 more you get ethernet and a sense connection, but bit less resolution. Digikey sells the first model for $335 and the 3 output model for $357. Amazon has it for $290.
According to the listing the display brightness can be adjusted so maybe it was just set on a low level.
I would rather compare those with Korad. I they have more precision than the Korad but without external sense I couldn't care less if it's high precision.
@@ppdan probably better built than Korad no?
I like how they are wide instead of tall, stack better on my bench anyway, instead of side by side.
First unit has too small a heatsink I am thinking despite the fan, and when you look closer seems like the Pcb has the footprint for a larger one.
Also, for best natural convection the heatsink vanes are orientated in the wrong orientation.
Overall, they are cheap and cheerful PSU's, and I think barely make it to the EEVBlog store quality product standard IMHO.
The vanes are the correct direction, just not vertical.
Although not a big heatsink, at least it has a thick base to help spread the heat better, and apparently transformer has multiple outputs to keep the power dissipation reduced, also it is very close to the fan, so it will be ok.
When you short out the output - does the current actually flat-line at 5.1A or does it briefly spike to 30A till the o/p capacitor discharges, and only then recedes to 5.1A? That initial pulse is enough to kill most sensitive devices; the 0.01mA resolution is meaningless.
Very nice handmade hippie resistors from the power stage
Those two supplies are so different from each other it makes me think they are made by different manufacturers, are they rebadged?
I believe they are both designed and manufactured by Matrix. The first one is much newer. Other one could be an old design.
I like many digits and precision, because it is convenient to use with low-power circuits. But they have to improve a front-panel design.
Are the triangle arranged outputs spaced to accept a standard side by side banana jack adapter connection? That’s a big deal if they are not.
I see no certifications other than the self-declared CE mark, how relevant is that?
I think the UIs are fine - maybe it matters more if they're used at Universities etc. where a lot of unfamiliar people need to figure it out?
One thing I can't get my head around though is why it's so rare to see equipment that actually controls fan speed, not just on/off. Using a PWM controlled fan shouldn't add much to BOM cost or firmware complexity, surely to many users that's worth it for quieter operation?
PWM fan control can cause interference, which may require additional financial costs to eliminate. In my opinion, it is better to use a linear regulator with a temperature sensor on the heatsink of the power transistor. But this also costs money for development and additional elements.
Owon makes some decent linear and switcher supplies which offer down to 1 mV settability with pretty good output tracking. There are both linear and switcher versions. There is an LCD screen with limited I and V output history tracking and serial port control as well. The one feature lacking is ability to have the output automatically switch on after a mains voltage recovery.
Owon is willing to rebadge the products, though I don’t know what volume to which one must commit. Here in the US, Newark sells them badged with their Multicomp house brand label. They’re pretty affordable not far off Ali Express prices, even with Newark making their margin.
I’ve got the 30 and 60 Volt single channel switchers and the 30 Volt linear and they’re all pretty good, provided you have realistic expectations.
Having a 5 V 2 A capable USB port on the back is a nice touch, especially if one could jumper it to be always on.
Build quality seems reasonable and the lack of binding posts on the linear unit isn't really an issue for me. (However, by the time one goes down to single mV adjustments, having a pair of sense ports becomes quite useful.)
Beyond that, the interface seems adequate enough.
Halfway through the video, I like the use of 7 segment LEDs for the display. Could do with making the amps readout red and the watt readout amber though.
The bodge resistors though. I was waiting for you to comment on your target price, and with the dented cap and bodge resistors, I couldn't see myself paying more than 100USD for this thing.
I get that the bodge resistors could be fixed in a later PCB rev and the dent is an attention to detail manufacturing issue, but like
ehhhhhh it just feels like an upmarket aliexpress unit with a cal certificate.
Maybe my opinion will change from the second half of the video.
The second unit uses the 2v pale green LEDs for the display instead of the modern 3v pure green LEDs. That's why the second unit's display was so much dimmer
Those are pretty nice.
Would love to see videos on testing the power supply
I am the only one that finds it weird to have a precision PSU without ext. sense?
The ui/firmware looks very similar (identical?) to the wanptek psus
STM32? . heatsink seem marginal ~50W (will work fine if ambient temperature 25 and fan is not faulty full speed)
Dented cap a pull-out from other device?
Yes it is very pretty Dave, but I bought a Yihua 3005D linear power supply with similar specs for $130 AU delivered. What about Wavecom 30V 5A DC Benchtop Power Supply - WCM-PS3005D $160 AU delivered.
I dont like the dimm green 7-seg display , the beeping & the split type bannana plug
It looks like to change voltage for ch3, press ch3 button and use the knob
Before processing to selling it I'd encourage to do some testing on it. Make sure that the specs are as claimed. Make sure that under worst conditions (output at short circuit) the pass transistor doesn't go over 100C. Make sure to test the loop stability by using pulsed load on the output with various voltage and current. Make sure that the switch from CV to CC under wrost condition is fast enough to not kill an LED. This is a huge plus if it passes.
Of course, that's a given.
I have a UniT 30v 5A jobby, cheap and works great. Just two knobs to set voltage and current. User interface doesn’t get any better! Although I freaking hate the cooling fan noise, no temperature control.
I like the Matrix’s switching PS! Looks like a desktop PC PS
I don't like the old LED displays and would prefer a good trans-flex LCD display for reading clarity. Yes, they are made cheap but some things need to stand out. Will you going to be doing a good function test for noise and such? I would like to also see how the output stands up to connecting a battery to the output in reverse to see how it stands up to a fault. I mentioned that as I killed a cheap supply doing that by mistake. Thanks
Nice display! I love it, output connectors, not so much, where are my posts! C'mon!
The single voltage linear has some pretty cheap terminals, not sure how long they will last with repeat cycling of lead insertions, but it has a number pad which I assume you can set V,I with. The larger one has better terminals but, as you said, still not as good as they can be; they need a cross drilled hole for wires.
The triple PSU has no numerical pad and having to fiddle with one rotary PB to set all of these V,I adjustments would drive me up the wall.. just me but I would not consider a supply of that calibre that has no numerical pad. Also its switching so I would be really attentive on the amount of noise it generates on the DC outputs.
Do these power supply jack spacings accommodate a standard dual banana jack adapter?
PS - Yes you can take the cover off without removing the handle... and stop calling me Shirley. :)-
What’s the output noise like?
What happened to “don’t turn it on, take it apaaaart”?
That second one looks nice; but it'd be good to have v-set and i-set buttons so then the control knobs are fine and coarse controls.
Could do that in software easily enough.
Are those output terminals 19mm apart on both units?
Yep, standard
19mm or 19.05mm ?
@5:15 "So that rules out the US market"
I am partial to linear PSUs and like the precision of the first one. Prefer binding posts with the through-hole. Bit of a shame about the dented cap and botch resistor. At least with the botch resistor some level of care went in to correct something, albeit after the pcb design. Personally I am not likely going buy a PSU because I have a number of linear PSUs already and I need to work on getting past 7805/7905/lm317 regulation.
Can you put 2 or 3 in series or parallel for increased capacity?
hmm... professionals will buy things like a BK Precision (my 1762 is >10 years old - but they still build these) and hobby users a Riden (I have a RD6006 with a 60V/350W supply). Not sure if there is much of a market.
That's disaster for the money Dave. Also those input terminals..missing caps, bent cap. That horrible resistor bodge.That's terrible Muriel
Completely agree. Don’t put your brand on those Dave - their quality doesn’t match that of your own brand and reputation….
"RTFM!" -- nice instrument though.
The secondary winding is aluminum, right?
I don't know, the interface on the dual (the one with the third channel that is fixed voltage), I really don't like, I would have prefered the interface on the linear one, so one encoder and an Iset and Vset buttons (or two each, for the 2 channels) and an enter button.
And now I am nit picking but the fixed voltage indicators look like they are all on, I would have prefered no color at all or to pay 2€ more and have colored leds instead of a colored sticker at the front
I was actually looking to buy an smps psu for my lab at the end of the year/start of next year, so if the thing you said in 0:58 actually happens, that would be amazing for me.
I'm really not taken with the knob-embedded-in-numpad layout of the first unit -- I don't know what UI problem that is trying to solve
RS485 interface with no ground reference?
I noted that too. It might work if the comms board has its own, isolated supply, but it didn't look like it.
Don’t put your brand on those Dave - their quality doesn’t match that of your own brand and reputation….
For the second unit that's some really nice Zip tie spaghetti you try to put your hand in that it's gonna bite you like An Aussie Spider Complete with folded wires And the ground is missing a zip tie
Why is the control knob in the middle of the keypad ? it's visually annoying :-)
Yeah, not the best.
The first one looks like a nice PSU if you fix it the way it should be, and I love those big old school manuals.
Watch out for beryllium in those electrolytics, dispose of them as if they were hazmat... Haha. But seriously, I'd recap both supplies, check out why someone botched that thing and put them to good use.
And I thought pressing a rotary encoder to move the across digits is very typical; I'm seeing it all over the place on Chinese digitally controlled PSUs.
No beryllium in those electrolytics, they might contain some aluminium only, in small amounts though.
@@SeanBZA just a pun on the brand name :)
Typical does not equal convenient. There is a lot of copying other's decisions without thinking *why* they made that decision.
Fans start at full speed to blow away the dust bunnies.
Brown glue that becomes conductive, with mains. What could possibly go wrong......
Can you tell what typeof it is it is from this video? , but if it is, that would be a blocker for me. I like the PCB design, but the build quality is sub-par. No sale as it is right now on both PSU's.
I absolutely hate this press it to move digit cursor (in one direction only).
Excellent way to blow up your DUT.
I am very curious about the RS232 isolation, from what i could see its not very inspiring
I wonder why my linear PSU is so much bigger and heavier than this one.. got to have a look inside
Arhh, quite a few things leaves a lot to be desired.
* Split sheetmetal on trumpcated sockets 11:04 split jacks that often gets weak with use, at least in cheap DMMs, not ideal on a relative high current precision supply.
* 7 segment displays with very limited info is asking a lot in 2024 where most units have graphical displays
* no secondary V/A set info.
* weak visual info for when the unit is "on"
- and whats up with that incl. powerlead,, did somebody step on it at the factory., as the connectors looks bend 2:48 .
and whats up with the casing on nr2 PSU the whole unit seems to tip the moment you lay your hand on it .. 16:32 or are the whole body simply bend, and maybe why the housing also lifts at the top, and the powerswitch also looks like its far from level.
Imagine if this PSU's were sent in 5 to 10 years ago, you would have teared it a new one, with "FAILS" ad'libitum. but the aspect of financial incentive and its gonna be your own product, maybe change the narrative... same with all the bigger caps "flapping in the breeze"
But anything have a price, so it do have a place, if you can sense a demand for them but this is pretty low end.. you can see that in the build... I would take a look at retail units around 100 mark to get your heading on what is out there, to sense what you can ask for these Matrix, as aEEVblog label, can only take you so far..
Aint Matrix also rebranding a lot of testgear?
Im not so familiar with them, but some of the Chinese optical testlab gear Im working with , also had some Matrix testgear, but some of it seemed to original from other lower end Chinese brands.. even Owon, if I recall, or maybe it was Unit-T?
Dave gets into drop shipping 😅
The pool needs to be paid somehow.
From my perspective:
1 channel power supply is absolute "buy the cheapest one as you just start up with electronics" IMO, and with any budget I'd go for dual . But keyboard is nice. Not nice enough to offset lack of binding posts. It's also overall takes as much space as dual power one woud, IMO that's one is a loser.
The second one IMO *needs* USB-A socket for the 3rd 5V/3A line.
The only time I'd use non-current-limited power would be for powering any other stuff that's not device under test (like various small devices that help with testing, or rPi the device is connected to) so USB-A socket would be nice for them.
I'd probably get one. USB, or at least an included adapter would be nice.
RS232! What's the point nowadays?
This is a amazing and excellent product, you are going to do really well with it! I wil order one right away!
Hi, Dave, I think it is sort of pointless to sell a power supply with this standard range these days, as everyone would already have something like that on their bench. A different matter is the extended range lab power supply, i.e. something that goes up to 120 or 240V, with lower amperage of course. Although relatively cheap devices like that do exist, this voltage is dangerous for both directly and indirectly (say, exploding cap). Therefore, much more trust and reliability are absolutely required from the power supply in this range. It would be great if you can find some reliable OEM, review it thoroughly and sell it under EEVblog brand.
21:40; YUK. ITS ALL 150K HERTZ TINY NOISEY TRANSFORMERS. YUKKK
No compliance markings? Must be an Aussie thing ,)
Along with the dent, the Samyoung cap also seems to have a crack on its top @9:38 and @10:07. Is that really a crack on its top?
That's a superficial scratch.
Hello,
I don't understand why eevblog would want to sell a power supply of a quality that you can find anywhere else. In Europe I would buy an RS Pro lab power supply. This has no buttons, just two control knobs and a PC interface.
The price is very similar, and the quality is probably the same.
And there's one thing I don't understand:
Why do almost no manufacturers manage to install a fan properly?
The air inlet openings are too small and too close to the impeller. This creates unnecessarily high flow resistance and therefore turbulence. This in turn generates noise. The same problem on the exhaust side. The transistors cooler is much too close to the fan and also in front of the hub. Exactly where the air flow is at its lowest.
I understand that a radial fan is not installed for cost reasons - it would be much quieter with the same airflow due to its characteristic curve.
In addition, there would be no resonance in the housing (the older Rigol oscilloscopes had the same problem).
However, I have absolutely no understanding for such a poor installation. There would be enough space in the housing. With axial fans, you should keep a distance of at least half the diameter - on both sides. This ensures less turbulence and increases the air flow rate. This allows you to reduce the speed.
As a result, the noise is less disturbing.
You don't need to have studied fluid mechanics to understand this.
Well, I do not want to judge about the other point which make a good or not so good lab bench PSU without testing it.
Chinese capacitors... next!
Oba te urządzenia, to jakaś porażka. Po prostu wszystko jest w nich fatalne. Planowałem zakup mostka lcr tej firmy, ale ten film uświadomił mnie w stu procentach, żeby tego nie robić.
나는 이것을 한국어로 입력하고 있으므로 당신도 그것을 번역해야 무슨 뜻인지 알 수 있습니다.
No 4 wire sensing abodge in a production unit no sticker on the standard unit this is not something you should sell as way too many bodges already
Anything decent available out of Taiwan with perhaps better QC and less political baggage?
+1. The company participating expos in Moscow in 2024 and making it news worth putting on their webpage, will get hard "no" from me.
Taiwan is a Chinese province.
Don’t bother, looking for trouble.
Nice ATRIX 😂
Even i
Yeah... massive chinesium vibes all over. Zero attention to detail in the design imo. Definitely not worth "a couple hundred" by the looks of it.
It's Progammable! Non of this Programmable nonsense 😂
9:30. YOu Know WHY it's BIG. FREQUENCY DIRIVED
ITS A 50/60 HERTZ JOBBY. ONLY REASON ITS THAT BIG
*ＷＨＡＴ?*
!
I'm happy to not have even a single example of gear like this in my lab. Have been dodging these types of Chinese bullets for a long time. If I'm buying on a budget, I go for high quality used stuff. All of my main PSUs are USA-made. I'm open to stuff made in Taiwan since that tends to be a level higher. Ultimately a lot of stuff out of China fails for consistently dumb reasons, poor solder quality, nearly guaranteed assembly problems (like the cap dent, questionable bodges etc - necessitating inspection of everything you buy from China), early failure on cheap encoders, corrosion on connectors/buttons, low quality wires, LEDs that burn out/dim far too quickly, fans that don't last etc. It's simply never made to last beyond the factory test. I refuse to be enough of a cheapskate to accept these tradeoffs. F that, honestly - I value my time.