lmao "stingray", with that overshoot it makes it all the more hilarious

That's huuuge overshoot, with the 20V back to de CC mode, it might blow up quite a few loads...

A transient analysis of various power supplies would make a great video. Not only on startup/shutdown but CC shorts and recovery while in process.

Pretty cool that there is no silkscreen but necessary designators and labels are directly in the soldermask and enig plated :)

The "X" notation is actually pretty common among other German manufacturers too. A lot of the CNC equipment I used to work on used Siemens controls. Siemens used the "X" prefix all over the place on various ports/connectors.

Nice for a basic model. Like the toroidal transformer, looks like an audio quality transformer. Good on you for the giveaway, I'm a member but won't enter because there are others who would need it more. Love that you're giving one away to a hacker space school. 👍

Its a bit hidden in the manual but: "Long press on the Back key resets the channel history information."

I had this in cart for the past few days. Glad I didn't pull the trigger before you uploaded this video. That overshoot is nasty. Thank you!

About the output terminals... they can do way over 120V, so they absolutely shouldn't be used without shrouded banana plugs because you can accidentally touch bare contact and get a nasty shock. So those type of terminals are acceptable.

Thanks for sharing the awesome content, allways amazed at your knowledge and attitude!

Software driven CC is a bad idea IMO. Give me an old fashioned analog loop.

I blew up my homemade bench supply and haven't had a working one since, hopefully I can nail the giveaway! Back to the vid!

Always fun to watch your vlogs

great video as always - I was just wondering; will you ever do a tear down/walkthrough of your own little power supply? perhaps even a big video going through all the prototypes leading upto it?

Wonderful show , even i don't get it all , but using that yellow pointer ! makes sense now , thanks

Oh! Nice tip about the output caps! I'm playing around in making a power supply and I'll keep that in mind! :) For an instrument of that price, I would expect a lot more polished functionality to be honest.

Generally a lot of manufacturers like to default to fan 100% on. I think it has several benefits. You don't know which state everything is in, so it might be hot as hell due to some power loss event or so. Fan spinup is easier at 100% and then throttling down than to try starting it at 5% or so. Users will earlier notice if something is wrong with the fan. Probably most people don't mind as they work with these and switch them on at most once per day

I’m not sure about the intent here with the initial high speed fan; it could be lackadaisical engineering or R&S meant to do it. I used to work in a datacenter, and servers often have banks of multiple fans and two fan banks in series to allow for a fan failure in one bank. Anyway, the Dell servers we had sounded like a 747 jumbo jet for about five seconds when initially switched on. There would also be a puff of dust out of the back of the servers. The servers stayed pretty much spotless inside. I concluded that it was no accident that the fans were initialized at the highest speed - it was to blow out the dust. It also gives the auxiliary “lights-out-management” supervisory processor an opportunity to check the health of the fans to see if all fans can meet or exceed an acceptable RPM threshold.

IMO, the BEST test of current limiting on a PSU is... 1: Set output voltage to the maximum it can produce (100V in this case) 2: Set the current limit to 20mA 3: Connect a 'garden variety' LED directly across the output 4: Enable the output If you still have a working LED after that, then it's _possibly_ a decent device. (I had to make HUGE changes on my own bench PSU in order to have LEDs survive this test even though it only goes up to 30V)

The fan on full blast on start helps unstick fans

Great resulation 👏👏👏👏

Thanks for exposing the quality.

That is a seriously cool and functional PSU

I'm to busy to do the give-out so keep up the good work dave... guess next time for me ...

Nice supplies, a 100V/200V supply would certainly come in handy when I'm fixing stuff. I really need to get hold of them again to see if they want to send me items to review, they almost did a couple of years ago but I hadn't reached 10K at that stage.

The ribbon cable to the front panel is touching the winding of the mains common-mode choke. A single-insulation ribbon cable is rated to 300V, magnetic wire insulation could withstand around 500V. I doubt that the device can comply with a breakdown voltage of 1500V.

Bummed I wasn't on the forum earlier, always been looking for a benchtop supply, oh well, maybe next time, might as well start posting haha

Your videos are great!!! Informative

The boys at Rhodes Schwartz where great guys to work with back in 1998 in Sydney. I remember my R and S instructor just off the plane from Germany. IF for RF we all scratch our heads at our instructors, because Germans talk IF instead.

Part of the 100% on fan at boot may be for testing, I know my little BK Precision does this and immediately says "FAN OK" after.

Hi Dave! Really curious as to how the voltage overshoot was missed by the designteam at R&S. Also fun to see you pull out a Keysight EDU power supply (another can of worms regarding programming output values and actual output). Love these hands on and real world reviews. Did R&S correct the statistics function? Because for bench testing it would be essential to easily reset the stats.

The overshoot has been taken care off according to information from R&S to mij dealer. How about an update about that on this lovely channel?

Interesting Power Supply. I have the NGE102 which is the two channel model in the NGE series. The operating software (firmware) is very similar and displays Min/Max values which I love. The Min/Max can be reset at any time by holding the arrow button for a couple of seconds under the “Menu” button. I have posted a short video demonstration of my NGE102 (“Rohde & Schwarz NGE100 Lab Power Supply Demonstration & RTB2004 Oscilloscope”) which was actually the “A” model upgraded by firmware update to the “B” model. I then believe it’s only the output binding posts and front colour that’s different. This video might be of interest if you are thinking of buying the two channel version. The three channel has a different firmware without Min/Max etc. I really love my NGE102, it’s a reliable compact power supply. It also had some great features such as “FUSE”, “ARB” and “RAMP” as standard. Unfortunately other functions like WiFi and Digital Switching are enabled by software licenses. Interesting video, especially the internals. Thanks.

The 0.021A is probably a really quick spike in the measurement due to capacitance or such. Too fast to show up on the display but it's there.

The max speed fan is a function of cleaning.

you had me at "feelovision", lol

Dave, could the overvoltage issue be a result of charging the output capacitor? Would be nice to see the actual current drawn by the load.

A bit better from one they did a few years ago which was what i'd expect from a college (not university) student project: an off-the-shelf switcher to provide 5V and then a bunch of switching regulators for other rails. Really, really noisy.

I assume they blast the fan at 100% on startup to blast out some dust. Some OEM PCs do something similar. Still annoying, though.

About the current range overshoot, I use the r&s hmp4040 and did the same experiments a few months back. Sadly I observed the same thing during overcurrent conditions, the supply seems to reach the full voltage and needs 10-20 ms to start current control. Unfortunately that's not good enough with the GaN devices I am measuring. If the device is unstable, it usually can't handle the initial surge of current during that 10-20 ms and it destroyw itself ... I wonder why it is necessary to have that 10-20 ms, it doesn't seem needed in a classic analog constant current control loop like the one used in the μSupply...

The 100V model is perfect for valve projects.

Sure shows up my Elenco (build it yourself) power supply kit.

Hello David That is a beautiful power supply and I also am not fan of those output jacks .

19:44 that Pmax of 0.36W was recorded when you first pressed the output on button because the output capacitors were empty and they simply charged, right?

I believe they're doing current regulation in software, that's why we see the stepping (hunting) on turning on the output, and that's why switching from CV to CC is so bad. What is the current resolution worth, if it blows through the limit almost any time you adjust the voltage up? And this is a >1600€ PSU… Jeez.

Wondering how power components fastened to the heatsinks. There's no screws. Is that yellow stuff a double-sided adhesive?

I am not too keen on R&S equipment, especially the high end spectrum analyser and oscilloscope, they run too warm in my view and seem to boot off an hdd with internal Os. if a glitch occurs(and they do!) they have to be returned. Then what happens when warranty has expired? On the PSU front, Kenwood used to make very hardy and robust power supplies, 60v/10A which will run all day every day for years!

Great stuff, micro actuator, all golden info. Except, you better real that "tounge" in. Suddenly my girl friend likes your videos, I'm sure the business trip to Australia is a coincidence ! HA HA. Well, we love your presentations ,esp "trap for new players". Would you consider explaining V double circuit and conflict of pos power on neg side of cap. Reverse polarity?, How high?,How long etc. take care.

Was expecting the hand with screwdriver with that statement :P

My 'bench power supply' is just one of those wall plug, switchable voltage with a screwdriver thingies. It has about 10.00% accuracy at best 😆

Nice one !

Oh, so I can stay with my 40ye old one with no issues ... Ok, it won't have waveforms and data logging but as a power supply it is better :/

You forgot to call it 'The money shot' once you opened the case and showed the internals.

Dave, did you check if there is a firmware update for the PSU? I had a thought that it’s just possible that they’ve corrected the over voltage problem in firmware but I’m no expert on these things.

It would be so awesome to win one of these for my birthday coming up!

Whenever someone opens some piece of electronics I'm thinking now: *"OOIii, what a surpROOOIIiise"* hehe

When did blue become the color of the low side of a power supply? Is blue plastic cheaper than black plastic?

I'm wondering what the current measurement across a sense resistor on a scope would look like...

Those overcurrent glitches almost certainly happen as it switches taps on that mains transformer when you change voltage..

@28:40 That initial spike is probably from the capacitors discharging and then the supply kicks in.

Sorry, but this much overshoot should be a FAIL not just interesting. And the biggest fail is not having separate output button for each chanel. Because of price ot is more targeted toward production, where communication is used, but more hobby friendly companies are known for coping bad ideas.

Can you show me as a beginner how you constructed your 2 amp load? Thank you sir!

10:01 Code Name, "Stingray". Makes your humble electronic workshop feel like it's part of some covert activity!

Nice review video

Looks like that 6 digit ADC was so expensive they could only afford 1 per channel and multiplexed it between voltage and current. When the set voltage is changed, it only monitors that and forgets about current for awhile. If you want 2 ADC's you have to pay much more.

Such bug discovered by one person in 15 minutes whereas in RS several people was involved in the project. Blamage.

How is the stuff pressed against the heatsink? I see no clamp or screw? The flaw with the constant current jumping during voltage change is shocking, seems to be a digital control stuff problem. Why not using analog control in a linear power supply. Of cource it could also be a digital input value with an analog control at the end. It also could be a problem with a range chage from the AC input voltage from the transformer taps, however. The 22 µF at the output is also Inconveniently large. Thanks for the insight and the tests, nice review like always.

Would be nice to get the psu for a review and then give it to someone else 😁

Teasing that uSupply in the background...

There are not so many power supplies around with that high output voltage, i need at least 2x60v (symetrical) for audio repair, is there any alternative?

3:10 ....No....gotta love the Ozzie crap colorcode.....That sells out the house....

I am sure this video will trigger a meeting or two at corporate. "Okay scratch EEVBLOG".

At that price, I would expect the power components to be screwed on and not mounted with adhesive tape like this.

Has the problem been resolved by the new firmware? What about the NGE and the HMC804x which also have an overshoot in CC?

Thanks for the teardown, what was the op amp part number?

Hello Dave The transformer have a lot of strings. Did and How R&S swichtes between them? Is a nice idea to save some Power

Those terminal colors aren't really European. Following NEC it should be red & black, following IEC it should be brown & grey, blue is used for center tap (0V) if present. Australia & New Zealand apparantly do have red or brown for pos and black or light blue for neg.

They put a entire microprocessor with memory for just a power supply. I think it's a overkill for something displaying DC data. But kudos to current measurement dynamic range.

It is too bad there is that chunky 21 uF capacitor across the output. The cap must be there to assure unconditional stability because who knows what ugly load might be attached. The shunt capacitance sort of negates the point of having six digits of resolution for the current display. The last two digits are essentially useless in many situations.

I just love my TTi PL601 90w linear psu which was about 400$ brand new and does not overshoot at all. Dave, just stop showing us rubbish marketing for newly released "premium" test equipment!

Could the Nonzero open circuit current be down to the leakage current of the capacitors NCC gives a leakage current spec for one of those caps of 0.02*CV+25, after five minutes, or 95 microamps. Seems the right order of magnitude, and it's probably conservative + you're not at the 160V spec. Would depend on where they'd mounted the current shunt I guess, seems like the capacitor is the last thing in the chain, which would make sense for minimising inductance/improving load regulation. Current might go down after some time under voltage though? Seems like a hard problem to solve if it changes/reduces over time- can't zero it out Another reason I guess to use smaller caps- less leakage You do seem to regain that second to last digit later in the video at 20v, maybe that last one is only viable at lower voltages, as the leakage current gets reduced. That or it takes a while for the caps to reform/stabilise, and you have to leave the machine on for an hour before using it.... Edit: would also explain the +500 microamps part- spec sheet says 0.04 CV+100 for leakage after 1 minute- 241 microamps. For 2 fused channels that would come quite close to 0.5ma Edit, transistor -> capacitor

Hi Dave, I have a question. I have a PV array on my roof (UK), do I need to worry about dirt, dust, bird poo. etc. It's rainy here unlike your end I guess. It's been there for 10 years, no trees above it. Cheers dude.

13:19 are the power devices just double-stick taped to the heatsink? I don't see any bolts. Seems a bit how ya doin.

Makes me wonder if their other equipment is similarly overprice mediocre stuff.

It would be interesting to see a resistive load periodically turned on/off via transistor to see how much time it takes to switch from CC to CV and back, and see whether it looks like the 22uF of the output or much worse.

Hi could you make a video for an entry level scope 2021?

Nice!

can you do one on the rp2040 board. Maybe make a board around it using parts

It looks more like Rohde & Bluez...

2 channel 100V model in the uk is £1400 BEFORE 20% tax and the digital triggers cost an extra £120 + 20% tax and the wireless another £180 + 20% tax... Thats £2040 inc tax...

And the Nichicon fan boys go wild.

Rohde obviously don't use their own oscilloscopes to test their equipment haha Besides don't expect getting their best stuff for that entry level sum.

That heatsink glue at 9:50 looks to me like the "yellow glue of death" that eventually turns conductive as I outlined here ukposts.info/have/v-deo/cZeidrCDhYN3xmg.html. I'm a bit sad to see a high end product from R&S using it instead of silicone. To be fair it's not on conductive components, but still it can become corrosive and brittle and stop working as intended.

22 uf @ 100V sounds like more than enough to ruin your day to me! (output caps....)

I wonder how it is acceptable at all to do the current limit in software. How can this be fast enough to prevent transistors from burning?

Nice PSU that will fit my needs nicely. For now I can pay only customs duty not anywhere near its full price. It is good investment and it will be long lived in some professional lab but unfortunately difficult to justify for average eevblog forum member.

Anyone know why they'd use more than one bridge rectifier? I thought it would just use one rectifier and split off to other circuits further down the line. What's the benefit?

not bad at all

At least they have TÜV Süd in Malaysia...

nice PSU