Keysight EDU36311A (rant) - Page 1
Forum section: electronics / testgear

author: capt bullshot
author_rank: Super Contributor
timestamp: April 11, 2022, 02:10:03 pm
content: Some parts of the EDU36311A must have been written by a clueless intern ...Use case:I want to test some DUT (nominal voltage 12V) over some voltage range. Starting at nominal 12V, then decreasing the voltage down to maybe 8V, then increasing up to 14V.So first step - enter 12V using the keypad and turn the output on.Next - turn the voltage adjustment knob ccw, voltage decreases by 0.1V.Adjust the step to 1V (using the cursor button)Turn further ccw until you reach 8V.Now start turning the voltage knob clockwise to increase the voltage by 1V per step.Works fine up to 10V - no you didn't notice the cursor changing the digit ...Boom - DUT is toast by applying 20V out of the sudden (because now one step is 10V, not 1V).Yes, I know there's an OVP setting which one could have set e.g. to 14V - but this doesn't do what would be useful here. It just shuts down the output, not limit the setting to a max. of 14V.But that's not the point at all, this is the stupidest implementation of a voltage adjust button I've seen until today. It acts as expected and suggests you're safe with what you're doing until it doesn't.Disclaimer: No human beings, animals or electronics were harmed by this experiment. Luckily, the DUT could stand 20V

author: mnementh
author_rank: Super Contributor
timestamp: April 11, 2022, 02:31:19 pm
content: Quote from: capt bullshot on April 11, 2022, 02:10:03 pmPerhaps they readyour signatureand decided to implement it in the firmware...?mnem

author: Zucca
author_rank: Unknown
timestamp: April 11, 2022, 03:45:55 pm
content: In 2022 all FW should be open source.The EE community is far more competent than some bored at work eng (maybe not well paid)This comes to my mind.

author: tooki
author_rank: Super Contributor
timestamp: April 11, 2022, 04:15:54 pm
content: Quote from: capt bullshot on April 11, 2022, 02:10:03 pmAs a former UX designer, I appreciate how awful that is! Yikes.

author: THDplusN_bad
author_rank: Regular Contributor
timestamp: April 11, 2022, 04:38:55 pm
content: I think this is what the palm face smiley was invented for ...

author: capt bullshot
author_rank: Super Contributor
timestamp: April 11, 2022, 06:45:46 pm
content: Quote from: tooki on April 11, 2022, 04:15:54 pmI don't need to be an UX designer, I've programmed such stuff (adjusting values by cursor keys) myself some 15 years ago. As I was the designer, coder, and (one, there's been customers, too) end user in one person, I knew how to do this right. Sometime it's hard, because it's not just a string but rather a physical value with influence to the real world. Though there's not that one "right" way, but what keysight did is clearly a sign of ignorance - fresh from uni bachelor boys PC or Smartphone App programmers / designers that never used any kind of TE (or other real world appliance) before.

author: floobydust
author_rank: Super Contributor
timestamp: April 11, 2022, 07:28:27 pm
content: This is terrible. Probably an issue when setting current as well? Not a 1A can do the same one-button click to boom 10A feature, but still a decade jump.I dare you to try submit the firmware issue to Keysight, let me know how that process goes. I find it takes way too much effort to write it up and submit it only to be treated as a "support request" and assume it's "user error".After a product is released, Keysight seems to have paltry resources allocated to fixing bugs or dangerous UI issues.

author: Someone
author_rank: Super Contributor
timestamp: April 11, 2022, 10:27:59 pm
content: Its not like they have the "excuse" of the number of digits after the decimal point changing. Counting the cursor position in digits on a number with variable digits, pretty funny. Almost the daily WTF funny.

author: J-R
author_rank: Super Contributor
timestamp: April 11, 2022, 11:21:29 pm
content: Quote from: Zucca on April 11, 2022, 03:45:55 pmSo then the BB3 should be excellent? But I think it's far from it. I picked one up last year but quickly became annoyed with having to use the relatively small touch screen for everything. It really needs a few more buttons. There are also some other odd behaviors and of course it is a switching power supply not linear.Firmware development seems glacial at this point. With the supposed flexibility, you would think they would have half a dozen UI configurations and such, but if you want that it seems you have to do it all yourself?But I didn't mind throwing some money their way and who doesn't like putting kits together? At the end of the day it does work.Current favorite supply is the E36313A. It actually doesn't even have a way to use the rotary encoder to adjust specific digits. But otherwise we seem to be on the same page most of the time via the keypad.Back to the EDU36311A, is the OP running the latest firmware? I don't see any specific notes about them fixing that issue, but there have been a few updates since the product came out:https://www.keysight.com/us/en/lib/software-detail/instrument-firmware-software/edu36311a-firmware.html

author: Brumby
author_rank: Unknown
timestamp: April 12, 2022, 01:40:57 am
content: I can see one way how such a result might have occurred - but it is programming laziness.The fact it made its way out into the market, is an extreme condemnation of their testing process.Just ... wow.

author: Brumby
author_rank: Unknown
timestamp: April 12, 2022, 02:32:49 am
content: Actually, thinking more about the programming - I'm suspicious about the whole approach being used.Things I'm curious about:1. What happens if: with the voltage is set to 9.9 and the increment 0.1, you step up 3 times?2. Is the output voltage tracking the expected (indicated) value - or does it take some transient value along the way?3. Do you see any strange behaviour when stepping down?

author: Brumby
author_rank: Unknown
timestamp: April 12, 2022, 02:34:45 am
content: Then again.... maybe Keysight is teaching by introducing the concept of "know your equipment" since thisisthe EDU series.

author: capt bullshot
author_rank: Super Contributor
timestamp: April 12, 2022, 05:44:43 am
content: I'm using the latest firmware, I've checked this first.The "quirk" happens each time the setting crosses 9.xxx to 10.xxx, no matter which digit you're on. When crossing 9.xxx to 10.xxx, the cursor jumps one position to the left, so if you're starting with 0.001 steps at 9.999V, and cross that magical border a few times the cursor ends up at 10V steps.Doesn't happen if you're decreasing the value and using less than 10V steps. At 10V step you end up at 0V and cursor at 1V step.The obvious hint what's happening: The power supply displays 9.999V, then 10.000V (there's no leading '0' or ' ' when it's displaying values below 10.000). So the cursor just stays at the same position from the start of the displayed string, but the length of the string changes.As the current setpoint doesn't change the length of the string, there's no such effect setting the current.Interestingly, dialing towards 0A ends up in 0.001A setpoint, and dialing up keeps that 0.001A -> 1A, 0.9A, ... 0.1A, 0.001A, 0.101A, ... 1.001AOutput voltage follows the setpoint quickly (about 10ms settling) with no over- or undershoot. Didn't test the current limiting behaviour, this is often desastrous, especially with the HPAK units I know.

author: Berni
author_rank: Super Contributor
timestamp: April 12, 2022, 05:52:02 am
content: This is the most appropriate use of the facepalm smiley i ever did on this forum.I would understand some cheep Chinese PSU doing this, but this is Keysight! One of the worlds top test equipment manufacturers!I suppose since it is a EDU unit the person using it is certainly going to get some extra educational value out of it about knowing your equipment as well as having to learn some troubleshooting steps to fix the circuit they have fried just now.

author: tv84
author_rank: Super Contributor
timestamp: April 12, 2022, 09:30:40 am
content: Quote from: Brumby on April 12, 2022, 02:34:45 amLesson 2: "know how to repair your equipment"Quote from: capt bullshot on April 12, 2022, 05:44:43 amMost probable cause. I guess the whole handling system is so "prehistoric" that even the acceptance procedure was not able to include such use cases...

author: Brumby
author_rank: Unknown
timestamp: April 12, 2022, 12:34:45 pm
content: As someone who first started writing test scripts in 1978, the whole exercise is checking for normal actions as well as abnormal - looking for ways things could go wrong. It baffles me how you could miss things like transitions across decades.

author: nctnico
author_rank: Super Contributor
timestamp: April 12, 2022, 12:43:33 pm
content: Quote from: Brumby on April 12, 2022, 12:34:45 pmI guess this is likely due to a new batch of software engineers taking over from the greybeards that all went into retirement at once.

author: Berni
author_rank: Super Contributor
timestamp: April 12, 2022, 04:27:56 pm
content: Quote from: nctnico on April 12, 2022, 12:43:33 pmYeah these days programmers think about things very differently.They appear to want to be as far removed from the hardware as possible. Everything is handled by libraries that use libraries that do the actual thing using a library. Nobody knows or cares how the thing actually gets done under the hood, they just care that it works. Memory is treated as being infinite and so are CPU cycles. Computers are fast anyway.Like for example my Agilent 34461A bench DMM takes ~30 seconds to boot. For a damn multimeter...On the other hand my Agilent MSO6034A scope boots up and is ready to go in ~10 seconds even tho this is an old scope from the 2000s that has a slower less performant CPU running vxworks.But but... these new DMMs have USB and Ethernet and all that, you need a proper WindowsCE OS behind it to make that work! Well.. that scope also has USB and Ethernet and it works fine... The power on self tests for a 4 channel 2GS/s scope are also probably more complicated than a run of the mill 6.5 digit DMM.It is not even all that impressive of a DMM as i keep using the Keithley 2015 DMM instead (That was designed back in 1998)

author: Bassman59
author_rank: Super Contributor
timestamp: April 12, 2022, 04:34:07 pm
content: Perhaps there's a way to report this bug to Keysight so they can fix it?They're not reading this forum.

author: tv84
author_rank: Super Contributor
timestamp: April 12, 2022, 05:25:42 pm
content: They don't support hobbyists...Only professional bugs are accepted.

author: tooki
author_rank: Super Contributor
timestamp: April 12, 2022, 05:44:02 pm
content: Quote from: Berni on April 12, 2022, 04:27:56 pmI don’t think it’s an issue of “wanting” to be far removed from the hardware, it’s a matter ofneedingto get things done quickly and cheaply because your boss is a bean counter and not an engineer.And libraries are a good thing: they tend to make thingsmorestable and reliable, not less! You think this bug here would have happened in a battle-tested commercial UI widget library? Unlikely. More likely, it’s the result of DIYing it for whatever reason.Abstraction is what makes modern software possible. It would be categorically impossible to write even distantly stable software with today’s feature sets without them. Reinventing the wheel is a bad thing. Letting one person write that wheelwelland letting us focus on our specialty is a much better approach. Not knowing or caring how it happens under the hood is a huge, HUGE advantage, since it is what makes portability possible.

author: Berni
author_rank: Super Contributor
timestamp: April 12, 2022, 07:37:47 pm
content: Well yes libraries are required due to complexity.I am talking more about slapping together more and more libraries on top of each other with each one being slightly abused to do the thing they actually need it to do, or not quite understanding how to properly use the library efficiently. The result being a product that performs oddly slowly given how powerful hardware it is running on while perhaps even being unstable at times.Why does my Agilent bench DMM take 30 seconds to boot? (It used to take even longer before the firmware update) What is that much more complex in a DMM as compared to a lot of my other test gear (like the old Agilent 6000 scopes, Rigol DP832..etc) that have similar modern interfaces like Ethernet and USB? What benefit does WindowsCE bring to the usability of a DMM?Another example are some of the slightly order Philips TVs. They also can take >30 seconds to boot. Once it boots you get a picture, after 2 seconds the sound comes in and after about 5 seconds it starts accepting button presses from the remote. But if you do open the menu in the first 10 seconds after it starts accepting input the menus animate in at about 5 fps. Once it settles in the menus start rendering a bit faster at 15fps while there is a clearly noticeable delay of about 1/3 of a second upon pressing a button and seeing the menu move. I have updated the firmware multiple times on multiple models, it never got fixed. None of the DVD players from 20 years ago ware this slow and clunky while they could still play video from USB. The modern Samsung TVs cold boot in <5 seconds and have smooth and responsive menus while having smart functionality.Similar story with 3/4 of car infotainment/digital dashes. They take a long time to boot only to offer choppy slowly responding UI once it does start running. Despite most of of them having hardware accelerated graphics hardware on board.Yes you do need a mountain of fancy libraries to get it to do all the modern features, but given that the thing is running on hardware possessing easily 10x the computational power. it should not run many times slower than its predecessors.

author: floobydust
author_rank: Super Contributor
timestamp: April 12, 2022, 08:51:28 pm
content: Quote from: Bassman59 on April 12, 2022, 04:34:07 pmLike I've saidQuote from: floobydust on April 11, 2022, 07:28:27 pmI found it's a demoralizing experience. They should offer $CASH$ rewards for finding dangerous bugs in their products, if they had an interest in being the best.They don't even have a way to submit a bug - it's all done as a support request, that you need help with their flawless products.

author: nctnico
author_rank: Super Contributor
timestamp: April 12, 2022, 08:54:49 pm
content: Quote from: Berni on April 12, 2022, 04:27:56 pmThat is not the problem. Some companies grew an engineering team quickly which then got old together without a lot of influx of new engineers along the way. Then the old engineers retire and are expected to transfer 30+ years of experience onto new engineers within a couple of months. In such situations details will be lost (*). A better approach for a company is to make sure the age across all departments averages around 35 to 40 years with an even distribution.Dave interviewed one of the R&D managers from Keysight a while ago and that person hinted towards having this exact problem.* And there is more to it. One of the problems I encounter personally when dealing with new engineers is that I often forget about the details I take for granted but which are not obvious at all for new engineers. After a few decades working as an engineer there is a crapload of stuff you do on auto-pilot.

author: kcbrown
author_rank: Frequent Contributor
timestamp: April 16, 2022, 01:25:23 am
content: Quote from: nctnico on April 12, 2022, 08:54:49 pmGood Luck With That. The only way to do that is to force early retirement onto the older engineers, who tend to be the most capable ones you have, or to get rid of your middle-age engineers who are just starting to become as capable as the older engineers.End result: you compromise the capability of your organization, make it worse than it would be otherwise.Unless your organization is large enough that you have a steady stream of people who are retiring, and can bring in young people as replacements,andhave an even enough distribution of age and capability both within groups and across groups that your remaining older people can step into the roles that were left by the retirees, you're going to have a really tough time pulling anything like this off.Engineering is one of those disciplines where youthful exuberance doesnotmake up for hard-won experience. Yes, someone who is relatively new and fresh can occasionally get a flash of brilliance and approach things in a new and insightful way that nobody else thought of before, but that's rare andcompletelyunpredictable, and often comes with its own set of tradeoffs (for instance, making rookie mistakes in the implementation of the new idea). Ideally you should have a mentorship arrangement where younger engineers are paired with older engineers so that the younger engineers can continually learn from the experience of the older ones. I don't know how often that happens in practice in hardware-oriented organizations. I'veneverseen it in the software world, because the software world is focused on doing things fast and cheap at the expense of pretty much everything else (such as maintainability, reliability, execution efficiency, etc.), and adopts idiotic development methods (e.g., "agile" programming) that pretend to be about quality but really are about speed of development and nothing else.

author: Someone
author_rank: Super Contributor
timestamp: April 16, 2022, 01:55:20 am
content: Quote from: kcbrown on April 16, 2022, 01:25:23 amThere are some very big companies who do manage this, but the scale required to have enough people in any given field (preferably in the same location/site and working on the same products) makes it unusual. One "trick", give the oldest employees part time contracts to taper off their working hours but retain their knowledge and mentoring (while ruthlessly firing anyone along the way who won't make it to such high levels). Not the most comfortable environment to work in when you have to keep showing growth/excellence ahead of your peers, similar problems in finance/accounting practices.

author: porter
author_rank: Regular Contributor
timestamp: April 16, 2022, 05:31:09 am
content: One bit of work philosophy I was taught at HP->Agilent was that everyone has five minutes for everyone else. Or something like that. I guess that way information isn't siloed, and the newer folks won't waste a lot of time...etc.

author: Berni
author_rank: Super Contributor
timestamp: April 16, 2022, 10:54:19 am
content: Indeed training up a good engineer is hard.You could have two engineering doctorates with top marks, yet are more likely going to be a shitty engineer if you don't have years of experience on real world projects.It takes time to absorb all the little details and good engineering practices. When starting out on your own you might have to learn a lot of these the hard way when your project blows up or performs poorly. But if you are working next to someone experienced you can siphon off those tricks a lot faster. Like asking the senior engineer to look at your schematic, watch him point out why some parts of it won't work or a bad idea, saving you from building a non functional board just to find out it is a bad design.Id say this transfer of knowledge is even rarer for software development. The senior guys might help with setting up the dev environment and fixing common problems, but i don't think they really go into the art of programing all that much. Sure they apply the algorithms they learned in school and all that, but that is the easy part. The more difficult part is architecting the higher level structure. You can really shoot yourself in the foot by just jumping straight in without a general plan of how to split up the functionality. You get spaghetti code that is all over the place, confusing to read, contains confusing names, difficult to maintain, gives more bug opportunities...etc

author: Keysight DanielBogdanoff
author_rank: Unknown
timestamp: April 17, 2022, 06:13:55 am
content: I've sent this thread over to the power supply team.The one thing I've experienced with their design philosophy for supplies is that the whole goal is to not accidentally put in too much power. That's why the knob acceleration is so slow, for example. The general recommended practice is that you shouldn't adjust power while the output is on. But, I do it with live outputs as much as anyone.

author: mnementh
author_rank: Super Contributor
timestamp: April 18, 2022, 01:51:05 pm
content: Daniel! We didn't chase you off with all the pushback over the whole "Commercial/Industrial Customers Only" thing.Hope we can resolve this quickly, get you a win.mnem

author: 2N3055
author_rank: Super Contributor
timestamp: April 18, 2022, 03:26:12 pm
content: Quote from: Keysight DanielBogdanoff on April 17, 2022, 06:13:55 amGood to hear from you!I assure you that 99% of people do change output voltage and current while output is enabled...These are lab power supplies and they are meant to be used for experimenting.

author: floobydust
author_rank: Super Contributor
timestamp: April 18, 2022, 04:45:02 pm
content: I checked the UI on Ruideng DPS5005 (theRD6006would be worth looking at too) and you can edit the setpoint digit by digit with the output enabled - but it won't let you change the 10's of volts, only the 1's of volts which can rollover and bump up/down the 10's. You just can't cursor over to the 10's digit. That limits it to 1V jumps max., might be the simplest fix.Or, you are allowed to change the PSU's setpoint when its output is on, but must confirm/press enter to accept it after editing/changing it.

author: alm
author_rank: Super Contributor
timestamp: April 18, 2022, 07:11:25 pm
content: Quote from: floobydust on April 18, 2022, 04:45:02 pmI think you described the UI of theAtten power supply Dave hated so much. I would hate both changes. I should be able to change the power supply by 10 volts if I want to, but it should not jump to larger increments when switching ranges. And I definitely should be able to change the supply voltage live, for example when watching when a linear regulator will drop out, without having to press 'enter' all the time.

author: mnementh
author_rank: Super Contributor
timestamp: April 18, 2022, 08:09:51 pm
content: I concur. Sooner or later, youwillwantsome modewhich mimics the organic flow of analog as much as possible, in which my preferred arrangement is coarse/fine adjustment knobs on both CV and CC.Why is it so hard to make this happen on digital PSUs? Why is it always either pushbuttons or a single encoder, and neither of which with an ideal UI but rather something which fails miserably due to trying trying to make it serve as both? The kind of money these tools cost, a numeric keypadanda few additional encoders is utterly trivial.mnem

author: floobydust
author_rank: Super Contributor
timestamp: April 19, 2022, 01:53:11 am
content: EDU36311Aalready has a keypad, two rotary encoders, arrow keys - how many more methods of UI do we want here? Wait until it gets a touch screenI think the issue is any of those methods making an unexpected, dangerous leap by an order of magnitude i.e. 10x is something unwelcome.

author: TurboTom
author_rank: Super Contributor
timestamp: April 19, 2022, 02:12:07 am
content: Quote from: mnementh on April 18, 2022, 08:09:51 pmFor what purpose? Coarse and fine regulators are a makeshift solution on analog PSUs when decent multiple-turn pots didn't fit the BOM for economical reasons. The four knobs are only confusing things and are prone to cause errors when having (had) to manually control several parameters at a time. Any properly implemented incremental encoder with a digit selector provides several such coarse / fine gradations. I agree that in some cases separate encoders for voltage and current can be useful. But a decimal keypad is even more important on a digitally controlled PSU.All the manual adjustments became less important with the advent of computer control of instruments. But in some situations it's still convenient to be able to "turn a knob" to change a value, and this ususally happens (in case of a PSU) with the output active. Hence, "automatically" changing the digit to be adjusted is more than a no-go, as many have pointed out already!

author: capt bullshot
author_rank: Super Contributor
timestamp: April 19, 2022, 05:42:58 am
content: Quote from: TurboTom on April 19, 2022, 02:12:07 am+1 on proper multiturn pots. Fine / Coarse is cheap crap.Though IMO encoder with selectable digit is the best digital way, and a keypad should be available too, nothing beats the experience and ease of use of a proper multiturn pot.I've got various lab PSU, here's my personal order of entry method preference:1. multiturn pot for voltage and current2. multiturn pot for voltage, standard pot for current3. select parameter by single keypress, enter numeric value through keypad, press Enter4. select parameter by menu or cursor keys, enter numeric value through keypad, press Enter5. separate digital encoders for voltage / current, with single keypress selectable and consistently acting digit6. anything else7. Coarse / Fine knobsAnd another one: Order of output terminalsMinus bottom / Plus aboveorMinus left / Plus rightorMinus left / GND middle / Plus righteverything else is anti-intuitive and annoying.

author: HighVoltage
author_rank: Super Contributor
timestamp: April 19, 2022, 09:03:13 am
content: Quote from: floobydust on April 19, 2022, 01:53:11 amThat is not acceptable in any PSU.The good thing is, that this can be solved in Software and a new FW update will probably fix this.Many years ago, the E36300 Series PSU had many more problems and the hardware had to be fixed and instruments were exchanged. At the end it was a very good PSU.The surprise for me is the fact that a company like Keysight would not detect these problems internally before they release such a PSU. Its easy to fix before it is released and a nightmare afterwards.

author: nctnico
author_rank: Super Contributor
timestamp: April 19, 2022, 10:48:47 am
content: Quote from: TurboTom on April 19, 2022, 02:12:07 amIt would be nice though when the knobs on a digitally controlled PSU would emulate a 10 turn pot. Best of both worlds. It would take a very fine pitched encoder though.

author: Sighound36
author_rank: Frequent Contributor
timestamp: April 19, 2022, 10:58:23 am
content: I shall be watching this thread closely as we have just taken delivery of four of these units for intern'sThanks for Capt Bullshot for finding this issue out excellnt work and glad the DUT didn't take a one way trip to MarsHope the Danny Bodegnaoff show can swing into to action and re address this issue in short time spell all our love from the MXR appreciation society first tester guild of the UK

author: Berni
author_rank: Super Contributor
timestamp: April 19, 2022, 12:41:24 pm
content: Multiturn pots can be annoying too. Going from say 3.3V to 12V involves a whole lot of knob twisting.For analong supplies i actually don't mind having a corse and fine adjust control. Just leave the fine control in the center most of the time so that you can turn it up or down when you need to fine tune it. (At least when the PSU doesn't do what this Keysight EDU does)I do prefer modern digital PSUs. They are quick to set and i can have a encoder knob that is exactly as fine as i need it. Can step in volts when i need to quickly get somewhere, or i can step it in milivolts when fine tuning something. Having a keypad is a nice timesaver bonus too since most of the time you need nice round number voltages.

author: mnementh
author_rank: Super Contributor
timestamp: April 19, 2022, 01:05:38 pm
content: Quote from: TurboTom on April 19, 2022, 02:12:07 amI disagree with this assessment. Multiturn pots are not assache-free in every situation; they are just adifferentflavor of assache in certainothersituations.I said this wasmy preferred arrangement.I like a multiturn pot for the fine adjustment; I just hate having to turn a pot a million times to get from say 5V to 35V. We're talking about what we want; everybody wants different things.I also do not want to give up the ability to direct-enter via a keypad. As I said earlier; at the price of these tools, adding a few encodersalong with a keypadis utterly trivial.Even dual encoders to emulate a single multiturn pot on each of CV and CC would still be a vast improvement overonly havingsingle-digit incrementation withonlypushbuttons.Maybe make the encoders so that when you press and turn, you can select a level of granularity, which is clearly shown on the display? Like being able to select from 10V, 1V, .1V, .01V, .001V etc per increment? Then maybe, just for safety's sake, another push to confirm that choice, and nothing actually changes until you start incrementing AFTER pushing the button?mnem

author: mnementh
author_rank: Super Contributor
timestamp: April 19, 2022, 01:12:18 pm
content: Quote from: Berni on April 19, 2022, 12:41:24 pmOkay... which models of digital PSU are you talking about? Havingboth, and having ausable UI, is precisely what I'm talking about. This is hardly a universal thing... or even acommonthing... with digital PSUs.mnem

author: porter
author_rank: Regular Contributor
timestamp: April 19, 2022, 04:19:41 pm
content: I think a foot pedal is needed. Maybe more than one.

author: mnementh
author_rank: Super Contributor
timestamp: April 20, 2022, 02:05:10 am
content: I need one. For my battery-pack spot-welder.mnem*tzzzt*

author: 2N3055
author_rank: Super Contributor
timestamp: April 20, 2022, 04:38:38 am
content: Quote from: porter on April 19, 2022, 04:19:41 pmMaybe a MIDI so you could use digital drums or any other MIDI controller.....Or maybe support for full HOTAS ...

author: Berni
author_rank: Super Contributor
timestamp: April 20, 2022, 09:40:02 am
content: Quote from: mnementh on April 19, 2022, 01:12:18 pmYeah some digital PSUs get it wrong.I use the Rigol DP832 the most and would recommend it. It is a good feature rich PSU for a good price. Sure the circular number pad is kinda weird but you get used to it and it does save a lot of front panel space. Some of the advanced menus are a bit confusing but the basic UI of setting voltages and currents and limits and all is nicely done.Sometimes even cheep ones get it right like the MulticompPro/Tenma/FarnellStoreBrand model no. 72-2690. It looks like your classical cheep two knob analog supply, but it has encoders instead of pots, you can move the active digit up and down and adjust it. It remebers the setting on power down. Simple yet effectiveSome of the larger Agilent made supplies (Like the rack mount ones) offten have both a keypad and encoder for setting them. They work well tho the UI takes a bit of getting used to.But there are certainly plenty of poorly executed ones. The Korad (the one dave blew up, i also blew up a similar one) is just plain anoying. The cheep switchmode bench supplies from BK Precision have a rather confusing interface. The TDK Lambda rack mount supply i got does have a simple and clear UI but it is encoder knob only with no velocity control (So you end up with the multiturn pot issue of having to turn and turn and turn and turn and turn to actually get to the voltage you want)But it is not only limited to PSUs. There are some instruments that i just find confusing to use for some reason. Like the menus of the Keithley 2100 DMM or the classical BK Precision electronic loads.

author: Thomas
author_rank: Regular Contributor
timestamp: April 20, 2022, 10:56:03 am
content: TTi MX series is the best I have used.Setting 5V on a channel is 3 key presses:<Vset softbutton> <5> <OK/Enter>They are, however, not perfect.The rotary encoder is accelerated (in a good-ish way), but I would have preferred left-right buttons below it to select the digit to adjust.

author: Berni
author_rank: Super Contributor
timestamp: April 22, 2022, 03:07:47 pm
content: That is a very well designed front panel.Controls very clear and spread out, minimized button presses for setting things etc. Also like the small sense wire connections (using bananas for that ends up way too bulky really quick on a multichannel supply.The one downside i see is no mili button. The Rigol does the setting in reverse where if you want 3A you press  then . But if you want 10mA you can press  [0 ] . Admitedly it is pretty rare, i mostly use it when setting the current under 1A for the initial power up of a prototype board.

author: Thomas
author_rank: Regular Contributor
timestamp: April 25, 2022, 11:09:16 am
content: That sounds nice. Many instruments do it this way, entering numbers with softkeys for units. I like it.On the TTi, 10mA is 5 key presses:<Iset> <.> <0> <1> <OK/Enter>Not too bad IMO, and it is intuitive.

author: TurboTom
author_rank: Super Contributor
timestamp: April 25, 2022, 01:33:53 pm
content: Quote from: Thomas on April 25, 2022, 11:09:16 amIMO, so far nothing beats Rigol's approach to enter basic parameters (Voltage Current) on their DP800 line of PSUs:Provided the channel to be configured has already been selected, there are two entries to be made since the instrument has dedicated A/mA/V/mV buttons that duplicate with the R/L/U/D arrow buttons and activate themselves after the entry of a decimal number. Hence, selection of current or voltage isn't necessary. To configure a selected channel (one keypress to select) to output 5V 500mA, a total of five keystrokes are necessary: "5"; "V"; "."; "5"; "A". The sequence of voltage and current entry is irrelevant. I really love this approach for simplicity and speed!

author: nctnico
author_rank: Super Contributor
timestamp: April 25, 2022, 01:37:36 pm
content: Quote from: TurboTom on April 25, 2022, 01:33:53 pmKeysight did that even better on the E3613x series. Assuming the voltage setting of a channel is already selected, setting it to 5V is a matter of pressing '5' and 'enter'. You can go through a couple of voltages quickly this way. The cursor keys can be used to 'walk' through the voltage / current settings of the channels.

author: TurboTom
author_rank: Super Contributor
timestamp: April 25, 2022, 01:43:18 pm
content: Quote from: nctnico on April 25, 2022, 01:37:36 pmJust checked with my DP832: This method is available here as well: Once the parameter to be adjusted is selected (Voltage / Current), entering a number and pressing the "OK" button (which obviously resembles the "Enter" key on the mentioned Keysight PSU), will change the parameter accordingly.

author: Patrick20
author_rank: Newbie
timestamp: April 25, 2022, 04:02:05 pm
content: Hi Capt Bullshot,In the future if you want to make this test easier to repeat without potentially damaging a device that is sensitive to 20V I would recommend writing a quick SCPI script like this one:(Connect "SCPI_E3631", "", "E3631 DC Power Supply / 2.1"):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 12(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 11.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 10.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 9.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 8.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 9.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 10.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 11.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 12.9(Wait 10000ms):SOURce:VOLTage:LEVel:IMMediate:AMPLitude 13.9I am setting voltage then waiting 10 seconds then setting it again. You can make this more elegant with Python, but this is just the quick and dirty. The programmer guide is a good reference as well.https://www.keysight.com/us/en/assets/9921-01393/programming-guides/EDU36311A-DC-Power-Supply-Programming-Guide.pdf?success=true**********I'm a Keysight employee, but do not support this product or help with the development of this product. I will see what I can do to send this issue to the correct team for review.

author: free_electron
author_rank: Super Contributor
timestamp: April 25, 2022, 04:13:41 pm
content: The cursor logic should set a step value. 10, 1, 0.1 , 0.01then every click is CurrentVoltag +/- stepThe ui render needs to postion the cursor based on step.It looks like they derive step from cursor position as opposed to deriving cursor from step....

author: LaurentR
author_rank: Frequent Contributor
timestamp: April 26, 2022, 05:24:28 am
content: Quote from: nctnico on April 25, 2022, 01:37:36 pmSadly, that's the only positive UI feature on that power supply.* Setting a current when voltage is selected involves turning the current knob a bit (!) then typing in a current with the numerical keyboard.* Unlike the EDU version, there is no per-digit knob-based adjustment. It's all absolute accelerated knob setting, which I find not useful at all. Coming from a DP832, I was quite unhappy.I even put together a small ESP32-based widget with a rotary encoder that drives the E36313A using SCPI to add the per-digit functionality.

author: Anthocyanina
author_rank: Frequent Contributor
timestamp: April 28, 2022, 05:57:13 am
content: The behaviour you describe in the first post is also how the EDU33212A behaves! cursor changing digit and all! So far just playing with it, but it's so annoying to be changing anything about the output signal and it jumping by 10 of something(volts/hz/symmetry % /phase angle) when you're expecting steps of 1

author: capt bullshot
author_rank: Super Contributor
timestamp: April 28, 2022, 07:21:03 am
content: Quote from: Anthocyanina on April 28, 2022, 05:57:13 amSo we know they've used the same bit of software in multiple devices. This doesn't make fixing that behaviour any easier, since more testing / QM / Managers will be involved.

author: Sighound36
author_rank: Frequent Contributor
timestamp: April 28, 2022, 04:49:08 pm
content: Quote from: capt bullshot on April 28, 2022, 07:21:03 amThis to me is big company mentality bean counter intervention, the Keysight MXR felt exactly like this a great product fighting to remove the shackles of medioricty constrained on it by the must fill the coffers syndrome WAY before the product is really ready for general public release.A great shame