RIGOL DP832 still a good Bench PS? - Page 1
Forum section: electronics / testgear

author: DriftlessNet
author_rank: Contributor
timestamp: June 20, 2021, 11:38:36 pm
content: HelloI am new to forum, but I have been lurking for awhile.I am in the market for a solid bench PS that does not break the bank. My main use's will include repair of older electronics, mainly older audio equipment, and occasional circuit prototyping for Arduino type projects.I seen a lot of reviews on the RIGOL DP832 and think it will meet my needs, but most of the information on it seems to be 5-7 years old. Just wondering if this is still considered a somewhat decent supply considering the price range I am in, which even the Rigol would be stretching my budget, so any alternative suggestions would need to be around that $450 range at the most.Also, I liked the version with the display outputs divided up into three columns, not the tri-looking arrangement on the DP832A, and just wanted to confirm that the base DP832 is still that way and hasn't been "upgraded" in more recent firmware as far as the display layout.Thanks!

author: Trader
author_rank: Frequent Contributor
timestamp: June 21, 2021, 12:02:34 am
content: What about this?

author: bdunham7
author_rank: Super Contributor
timestamp: June 21, 2021, 12:38:07 am
content: Unless you want the additional gizmo displays and features, I think they arejust too much moneywhen you take into account the unrepairable failures, turn-on surges and so forth. I personally have not purchased any of these new supplies and I have several older models that work well--they reliably produce power. If you do want a new, fancy one, the maker space I hang out at sometimes has a Siglent 3303X which seems very solid and nice, the 3303X-E is similar but less money. Also, from a previous discussion of power supplies, userArthur Dentended up with a GW Instek model that he was quite pleased with and I believe it was much less than the Rigol. You might want to search the forums for that discussion.The PSU that I have that with the sort of power outputs that you are looking at (0-30V, 2.5A x2, 5V x 1) is an old Tektronix PS280, not actually Tektronix made, but OEMed by GW Instek. It's heavy and the fan blows a lot of air, but it gets the job done--and I use it pretty much the way you intend to. It's also repairable unless you drop it on the floor, and then it still might be.https://www.ebay.com/itm/324547289581?hash=item4b9086a1ed:g:J7EAAOSwQ7dgY7AoEDIT: watched the video, the issue of two channels sharing the same common ground is a problem that won't matter until one day something goes up in flames.

author: DriftlessNet
author_rank: Contributor
timestamp: June 21, 2021, 04:43:38 am
content: Appreciate all the good input.From the updated videos and reviews I saw posted since the original EEV Fail video, I thought the DP832 was updated to address most of the earlier issues. When you mention the "unrepairable failures" are you referencing specific faults of the DP832 or just the general inability to repair more modern electronics as easily as older equipment?The old Tektronics does look interesting, I will need to consider used equipment in my search. I do not need a lot of the "newer" features, but I do like the idea of all three channels being displayed simultaneously with relevant info on all three. I also would like a unit with a timer function as I plan to occasionally use it as a battery charger for a few oddball sized rechargeable batteries I have. Not necessarily a must have, but it would be a nice to have.One issue that does concern me is the turn-on surge from the above linked video, I was unaware of this fault from my earlier research. I was reading through the DP832 manual and noticed it has two modes for start up, Last and Default. Is the turn-on surge issue present in both modes?

author: riccardo.pittini
author_rank: Regular Contributor
timestamp: June 21, 2021, 06:59:10 am
content: I use several DP832 in the lab.The Rigol DP832 out of the factory often came with a firmware that had the turn-on spike issue (I also observed spikes of 30V for 0.5-1sec, not just a low energy spike but it could power a fan!!). I contacted support (Batronix, excellent support) and I got a firmware update.Firmware update fixed the spike issue.

author: DriftlessNet
author_rank: Contributor
timestamp: June 21, 2021, 11:52:37 am
content: Thanks Riccardo for the letting me know about the firmware fix for the reported power-on surge issue.I will say that after hearing about the power-on issue it was bugging me a bit and started to sway me away from even considering the DP832, so I am glad to hear they are addressing these issues and there is a fix in place for it.

author: mindcrime
author_rank: Unknown
timestamp: June 21, 2021, 02:14:22 pm
content: I use a DP832A and I love mine. I haven't compared it directly to a lot of competitors, but in terms of daily use around here, it does everything I could want and more. Never had any issues with it, in ~2 years of usage. (Knock on wood!)

author: DriftlessNet
author_rank: Contributor
timestamp: June 22, 2021, 02:57:05 am
content: Quote from: mindcrime on June 21, 2021, 02:14:22 pmThanks for the input. The more the feedback from existing owners the better as $450 or so is a sizeable investment for my budget and I don't want to end up regretting my decision.With that said, the more I look around and research the more I think I am still leaning toward the DP832. I briefly thought about the multiple independent supplies mentioned in the above video and even looked at some used equipment, but I really like the DP832's display and the idea of timer controls for my uses. My intended use will require at least two sources anyway, and having it all in one chassis is also quite attractive. I do wish the price was about $150 cheaper, but I guess that is the cost to get a somewhat usable supply that isn't total junk.One other question, I know one 30V output shares a common ground to the 5V output, but has anyone had issues using the two 30V channels in serial? I don't foresee a lot of heavy use at 60V, but I anticipate the occasional need for something greater than 30V from time to time.

author: Dubbie
author_rank: Unknown
timestamp: June 22, 2021, 03:01:00 am
content: I have had a good run with mine. It's a very solid power supply across the entire range.The UI is really ugly and clumsy, but I have eventually gotten used to it.Value for money I haven't found anything to replace it.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 22, 2021, 06:36:24 am
content: Mine is still working OK. Didn't had any problems so far.If it were to buy again, I would look for something without a fan, not sure if there are any. In a lab at home, DP832 is noisier than the oscilloscope and the desktop combined. At low power the fan noise is still tolerable, but at average power the fan turns to high speed, and it become unbearable for long term.Another thing is that when the DP832 is turned on, during boot, some units are outputting a spike of current on the channel one, so before powering the DP832 up, better unplug any low voltage circuit that are connected to channel 1.For devboards like Arduino, I always power them from the 5V USB, or from a wall adapter of the desired voltage. Otherwise it would be too noisy for me to keep the DP832 while writing programs.

author: nctnico
author_rank: Super Contributor
timestamp: June 22, 2021, 07:50:16 am
content: The GW Instek GPP4300 series is worth looking at (https://www.gwinstek.com/en-global/products/detail/GPP-Series). At least it has isolated channels and on top of that it can function as a DC load. If I have to buy a bench PSU nowadays then this would be my choice.

author: DriftlessNet
author_rank: Contributor
timestamp: June 22, 2021, 10:37:34 am
content: Quote from: RoGeorge on June 22, 2021, 06:36:24 amI have heard the noise only in videos, but that isn't a realistic assessment of what it would sound like in my environment so I appreciate any insight on if this is something that can be at least reduced. Do you think it is due to the actual fan itself or more the case design and it the airflow causing most of the noise? Do you think swapping out to a Noctua fan and maybe utilizing rubber mounting would help?

author: PartialDischarge
author_rank: Super Contributor
timestamp: June 22, 2021, 10:58:59 am
content: Quote from: nctnico on June 22, 2021, 07:50:16 amI'm not very keen on the looks of GWInstek scopes, but since I bought a GOM804 microohm meter from them, I really like their instruments, and this line of power supplies seems great and good price too:https://eleshop.eu/gw-instek-gpp-4323-programmable-power-supply.html

author: DriftlessNet
author_rank: Contributor
timestamp: June 22, 2021, 11:07:14 am
content: Quote from: nctnico on June 22, 2021, 07:50:16 amThanks for the suggestion, I'll check it out.

author: rsjsouza
author_rank: Super Contributor
timestamp: June 22, 2021, 11:16:09 am
content: Quote from: nctnico on June 22, 2021, 07:50:16 amWow, this is a solid recommendation - GWI tends to have reasonable quality and the combination with an electronic load is quite interesting for the price.Unfortunately they are not as popular as other brands, but fortunately EEV to the rescue:https://www.eevblog.com/forum/testgear/gw-instek-gpp-3323-psu-fan-noise-on-idle/

author: RoGeorge
author_rank: Super Contributor
timestamp: June 22, 2021, 03:32:51 pm
content: Quote from: DriftlessNet on June 22, 2021, 10:37:34 amI have Noctua in the desktop, where they made a difference because there is plenty of space to use larger fans with slower RPM, but I don't think there will be much difference with the power supply, where the space is limited. It's mostly the air that makes the noise. Then, if you modify it then you loose the free service period.Anyways, looking at those GWinstek it seems like a much better choice IMO, especially for being able to act like a load (if this is really the case and not just some marketing lie). I've needed a controlled load many times, and had to improvise because DP832 can not act as a load.

author: DriftlessNet
author_rank: Contributor
timestamp: June 22, 2021, 09:20:59 pm
content: Quote from: RoGeorge on June 22, 2021, 03:32:51 pmI was more meaning doing a modification down-the-road, as you are correct I would not change anything until I was quite happy with the performance. I don't believe anyone would want to risk the warranty being voided over a bit of extra noise. You are probably right on the noise most likely being due to restricted airflow around the components and being pushed out the stamped grill on the back.I do know Noctua fans are usually anywhere from a few to several decibels lower that the competition, but these measurements are usually of just the fans running in free air with no restrictions. I have replaced many standard fans with Noctura over the years with mixed results. I usually can get some reduction though by also incorporating some type of isolation mounting, (rubber, etc.) instead of the fan being bolted directly to the chassis frame. In a case like this, where the vents are comprised of stamped out slots on the back panel, I would normally cut that part out leaving the circular hole and mounting a metal fan guard in its place which allows a lot more airflow with its thinner wire profile and smooth rounded edges.Anyway, I was just trying to look at it from the perspective of if there were any potential "fixes" that might be available in the future if I found the noise to be too offensive. I don't want to rule out an otherwise perfectly good supply just because in its factory configuration it is noisy, but on the other hand if there are no good solutions than the excessive fan noise would definitely be a negative.

author: thm_w
author_rank: Super Contributor
timestamp: June 22, 2021, 11:12:53 pm
content: https://www.tequipment.net/Instek/GPP-3323/DC-Power-Supplies/Lab-Power-Supplies/$540 and it has two outputs, third output is semi-fixed, not adjustable current. Enjoy your low voltage circuitry at 5A.QuoteSo you get a 100W load, but you are paying $70 more. IF you want programmability and one channel PSU one channel load, then that is great. If not, better off just saving that $70 to buy a cheap external load.

author: 2N3055
author_rank: Super Contributor
timestamp: June 23, 2021, 06:37:34 am
content: Quote from: thm_w on June 22, 2021, 11:12:53 pmOn multichannel versions it is 50W for load per ch, on first 2 ch. 100W is only for single channel model.

author: nctnico
author_rank: Super Contributor
timestamp: June 23, 2021, 08:44:26 am
content: 2 channels in parallel gives a 100W load

author: wizard69
author_rank: Super Contributor
timestamp: June 23, 2021, 06:43:45 pm
content: You didn't mention how far along you are with a lab build. In any event I have to admit that I'm not a big fan of the rush to power supplies while the rest of the lab is lacking more important tools. So I can't even suggest a multi supply power supply if your lab is lacking other tools.Quote from: DriftlessNet on June 20, 2021, 11:38:36 pmAn Arduino can run off a plug pack.As for repair, how often does somebody make use of a power supply to repair audio equipment? I'm just not convinced that a power supply will be put to use all that often for audio repair work.As for "old electronics" that really depends upon what you are repairing, even here though how often do you need a triple output supply?QuoteIf you need to stretch the budget then don't, especially for a power supply. I just don't see a power supply as being worth it.QuoteMy suggestion would be to focus on single output supplies which can be had for far less. One supply is likely enough to get your started. This especially if the Arduino is operating off a plug pack or other fixed voltage supply.There are other advantages to single output supplies. For one as you build out your bench you can have redundancy. That is you don't loose all of your power sources as you would if a multi-output unit goes down. Single output units are often smaller and likewise you can save space by only having the number on the bench you need.In any event the number of power supplies you might need is really a function of what you are doing at the bench. I'm just not convinced there is a pressing need, for a bench focused on audio equipment repair, in most cases. It is a whole different game if you are getting into the development of audio equipment where you may need many different supplies. You may need a supply on a repair bench but I wouldn't spend a lot of money on it. Further that supply you buy might not be the right one when you need it, buy a 30 volt supply when your repair problem demands a 72 volt supply and you will be frustrated.

author: nctnico
author_rank: Super Contributor
timestamp: June 23, 2021, 07:07:27 pm
content: There are 2 problems with wall-warts (you probably mean that by plug pack)1) They may have half the mains voltage on their output which will immediately destroy any logic input which somehow is grounded2) They have no current limit so it is very easy to fry a circuitIf you really want to go cheap then it is still a good idea to get a PSU with a current limit and personally I like to have some resolution in the readouts of a PSU. No less than 4 digits for current and voltage (assuming a 30V / 1A power supply). It won't be accurate but at least you have a meaningful resolution. With less digits you'll see that you always need a multimeter to check voltage and current. That is just clumsy to work with. Also make sure to buy a linear regulated power supply. Switching power supplies like the ones from Gophert and Rek are great but only to serve as an adjustable wall-wart for a project which is finished or devices which need DC power; switching power supplies have too much noise on their outputs to be useful for development work. The noise will turn up on your oscilloscope making signals hard to see.

author: DriftlessNet
author_rank: Contributor
timestamp: June 24, 2021, 02:18:53 am
content: Quote from: wizard69 on June 23, 2021, 06:43:45 pmYeah, I do need to round it out with some other equipment as well, that's the main reason I want to stay under $450 with a PS. I have thought about going with a single PS and adding more as time goes on, which is probably the smartest way, but at some point I would probably want three channels anyway and bench space will be more of a premium than money.QuoteYeah, I do have a lot of power packs currently in use for various projects, but would like a bench supply for new circuits. I plan to get more heavily involved in the hobby as my interest has grown. I only mentioned the audio work as indicating I would prefer a linear supply, as otherwise I figured I would get a lot of switching type supply responses so I just addressed that from the beginning. I also would like to build my own audio power amp(s) one day, as well as a few other ideas I have, so wanted to be prepared for that time.QuoteWell its not so much as can't afford as don't want to. After some research it is apparent that this hobby, much like my other ones, can quickly go from hobby level to serious $. I am just trying to set a realistic budget for myself up front so I don't convince myself I need that $1,000 PS and such. Like most people I want the best bang for my buck, but I don't want to go so cheap as to regret it later and then end up spending more money anyway. So by all means I am looking for the best honest opinions, if people truly think starting out with a single PS is the best route I surely will consider it.QuoteAgain, I appreciate your honest opinion. Got me thinking seriously about going with a single PS to start. Any good ones to consider? I hear a lot about the Korad KA3005P, is that a good place to start or something else?Its probably best served in its own thread, but I will need to add to the lab at some point. I do have a background in electronics (Allee Hall, if anyone gets the reference), but that has been some years ago and I have been doing Network Engineering work since, so not a lot of electronic hands on. The last few years with the Pi and Arduino projects I have really begun to get into it again and would like to start to build my own circuits to integrate even more ideas.Anyway, long story short, I thought I would re-educate myself as I built up the lab, by building simple circuits as I read books and follow along videos. My thoughts were to start off with a decent PS and a Scope. I have some lesser gear and tools already, couple DVM's, soldering stations, etc. but no bench type equipment.

author: tautech
author_rank: Super Contributor
timestamp: June 24, 2021, 05:06:57 am
content: A SPD3303X-E is reasonable value at $ 389 but the 3rd channel is only 2.5/3.3/5.0 V @ 3.2A.At least it has 3 properly isolated channels and good power ON behavior.That you can also series units to a max of 500V can be useful if you require that sort of capability.

author: justme1968
author_rank: Contributor
timestamp: June 24, 2021, 06:53:19 am
content: i‘m also looking for a bench power supply and was looking for the dp832. my main concern was that is is quite deep. but yesterday i found these two videos:and i‘m quite disappointed. his device is 5 years old, but has anything changed since then?regarding the size: something the size of a the korad would be nice. or the size of the dg800/dg900 series. with just 1 channel each but stackable. so it can be expanded over time. the stacking would allow tracking and parallel/series mode without the need to adjust each device separately. does something like this exist for a reasonable price?i have also seen the comparison to 3 korads and there are some of my arguments. but my korad is also loud and buttons and the knob start to be flaky.

author: 2N3055
author_rank: Super Contributor
timestamp: June 24, 2021, 07:09:50 am
content: Quote from: justme1968 on June 24, 2021, 06:53:19 amWhy wouldn't things be changed? If that was a problem in all supplies there would be thousands of reports of them dying out there...There were some problems of first revisions, overheating, this PSU problem and display problem (My DP831 had that). They gave me brand new one that was new revision and it's been solid for years now...I would be wary about buying older used one (because I might get one of those first revisions with problems), but buying a new one shouldn't be a problem.But as many pointed out here, there are other options that might be better for your need, be it smaller, more functions etc etc..I won't get into which one to buy, but I will tell you this: being able to readback voltage, current and power of DUT directly, with good precision, is something I use all the time.Also, being able to control it with PC (or Raspberry PI) is another thing that is useful. Smart PSU are very useful if you take time to use advanced capabilities.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2021, 07:11:57 am
content: Quote from: tautech on June 24, 2021, 05:06:57 amBut no numeric keypad which is essential on a digitally controlled PSU. Without a numeric keypad you keep twisting the knob ad nauseam. It is just too tedious to operate.

author: Berni
author_rank: Super Contributor
timestamp: June 24, 2021, 07:45:53 am
content: The DP832 is a bit expensive but it does bring a fair bit of bang per buck.It is a nice PSU when you need multiple channels. Much more convenient than using separate PSUs. The common ground between Ch2 and Ch3 is not really that bad once you get used to it (You often need the digital rail to be commoned up with something else). Unlike most 3 channel PSUs the Ch3 is a proper channel with adjustable everything, this is very nice to have in my opinion. You can also hack all the options on it easily. It does have some quirks but its not too bad. The fans can also be replaced with quieter ones, it makes it much less annoying to me.These Korad supplies and similar are fairly poor build quality. Dave blew one live on video, i blew up one myself within a few days of getting it. I was not impressed

author: tautech
author_rank: Super Contributor
timestamp: June 24, 2021, 08:32:16 am
content: Quote from: nctnico on June 24, 2021, 07:11:57 amNot so, select the unit to adjust and turn the encoder.The fact that we're always out of stock of SPD3303X-E might suggest otherwise.More are on the way and just about to order even more.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2021, 09:08:33 am
content: You know what they say: there is a sucker born every minuteOnce you have used a digitally controlled PSU with a keypad you'll never want to use one with only a twisty knob.

author: Berni
author_rank: Super Contributor
timestamp: June 24, 2021, 11:07:54 am
content: Quote from: tautech on June 24, 2021, 08:32:16 amAlso have digital PSUs that do that encoder knob thing, it is better than a analog knob but still pretty annoying to use.On the DP832 if i want to have 5V at 200mA i just key in 5 Volts 2 0 0 miliAmps. No need to even select what i am going to type, it just knows that its voltage when you press the button for volts. Only thing to watch out is to make sure the correct channel is selected. Its faster to type it in, also requires no looking at the display (as you would have to look what digit you are turning). If i do want to set it with a knob (Like fine turning the voltage up and down live) i can still select the appropriate parameter and spin the digits with the knob. Having both options on hand i always pick the numeric keys for setting a fixed nice round voltage number. Even with the rigols weird circular numeric keypad (you kind of get used to it eventually).

author: rsjsouza
author_rank: Super Contributor
timestamp: June 24, 2021, 11:26:26 am
content: My US$0.02Quote from: DriftlessNet on June 24, 2021, 02:18:53 amHave you considered building your own? Power supplies are relatively simple pieces of equipment and provide a great learning experience, especially when suited to the power levels of Arduino and Raspberry Pi. The reason I mention this is because you seem to have passed that level of knowledge where everything is daunting and seems insurmountable.Another alternative would be to try and find an used but older model in the local market (Craigslist, Offerup, etc.) - although the risk of getting something that has a failure is higher, the classic models (from HP or Tektronix for example) have full schematics and service information and can be a good platform to learn a bit more. Obviously that the selection becomes more restricted to what is available in your market, but it would be certainly a cheap alternative with a lower risk of regret.I, just like many on this forum, spent most of my hobbyist (and then later professional) life using single channel power supplies. Sure, in the 1980s/1990s lab power supplies were mostly out of reach for the common man, so we had to make lots of compromises.Quote from: tautech on June 24, 2021, 08:32:16 amAlthough the keypad is not 100% mandatory, it is indeed quite helpful. A bad twist on the knob and your circuit may go up in flames. Also, if the voltage/current is far from the current set point AND the firmware is not well implemented (without encoding accelleration, for example), the twisting becomes tiring quite fast. Another aspect is the sheer quality of the encoder used: in typical low cost equipment, the wear and tear of encoders is quite severe.Does that mean the Siglent is a bad contender? Not at all, but if you can choose and is within your budget, this is an important factor to consider.The popularity usually means the power supply performs decently and has a very good price point, but it has just limited correlation in a comparison between models/manufacturers.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2021, 12:16:09 pm
content: BTW a nice PSU on the used market is an Agilent 66311 (15V 3A IIRC). It needs a different Noctua fan to reduce the noise a bit but other than that it ticks a lot of boxes. The dual range current display (with uA resolution for the low range) is very handy.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 24, 2021, 03:59:57 pm
content: Quote from: justme1968 on June 24, 2021, 06:53:19 amRigol fixed that design mistake many years ago.The very first design was like the one shown in the video. Dave caught the reset problem in a video, too, many years ago, and as a result Rigol changed their design adding a radiator to that voltage stabilizer. They do not produce the malfunctioning design any more. The additional radiator can be seen from outside, without opening the unit, so it's easy to identify if by accident you receive an old stock with the design bug.LATER EDIT:Found it, that was in 2013:https://www.eevblog.com/forum/blog/eevblog-512-rigol-dp832-bad-design-investigation/msg284232/#msg284232

author: justme1968
author_rank: Contributor
timestamp: June 24, 2021, 04:08:46 pm
content: thanks for the heads up! so it will probably be a dp832 after all. if it just were a little less deep...

author: RoGeorge
author_rank: Super Contributor
timestamp: June 24, 2021, 04:43:00 pm
content: It is very deep and very heavy. Not recommended for a normal office desk.My workbench had a shelf extension in the back, making it 85cm deep, so I can align the front panel of the DP832 with other instruments. A casual desk is only 60cm deep, that will left almost no room in front of a DP832.The good news is it can stand eventually on the floor, like a desktop. DP832 has deep corners with rubber pads and a 90 degree power cord plug, so it won't damage your cables when sitting on its back panel, on the floor.

author: thm_w
author_rank: Super Contributor
timestamp: June 24, 2021, 09:26:22 pm
content: Quote from: rsjsouza on June 24, 2021, 11:26:26 amAt that point I would just get a RD6006 and build my own case around it. But you need access to salvage PSUs, craigslist or second hand store.https://hackaday.com/2020/03/16/review-the-riden-rd6006w-dc-power-supply-module/

author: rsjsouza
author_rank: Super Contributor
timestamp: June 24, 2021, 09:39:00 pm
content: Quote from: thm_w on June 24, 2021, 09:26:22 pmThat or a big transformer, four diodes, a large capacitor and a suitable box.

author: DriftlessNet
author_rank: Contributor
timestamp: June 25, 2021, 04:44:33 am
content: Quote from: rsjsouza on June 24, 2021, 11:26:26 amActually I have build a couple of PS's over the years, the last one being some time ago but it has since got lost somewhere in a move after I lost interest and was neck deep in work related worries. It was when you could still walk into a local RatShack and pick up the all the parts you needed, to give you an idea, not counting their last few years they spent as a glorified Cell Phone store.Anyway, as you said I am a bit past that, but still want to hit the ground running as I refresh my knowledge. My first go around was mainly practical knowledge and the hands on learning, with very little (just enough) of the theory and math behind what was happening. While that was plenty for my job at the time, it only really seemed to be good for repairs and constructing simple circuits such as power supplies. When trying to design more complex projects I seemed to get hung up and I think it was due to the lack of the math/theory knowledge (and decent lab equipment). I could easily follow a schematic, or a plan in an electronics magazine, to build something, but I never could sit down and design a more complex project on my own from scratch. That is the direction I want to head now that I have more time on my hands.As mentioned earlier, I have build several things now using Arduinos and associated shields, but again these are almost "finished" projects from the perspective I am looking at. I don't claim I will reinvent a Arduino, but maybe designing/building a few custom shields sounds like fun. I also want to design/build my own Audio Power Amp, just two channel and maybe a separate sub amp as a more immediate challenge.Anyway, maybe I will just get a single PS and work on a home built 3-channel to start after I bone up on the topic a bit more. Thanks for your input btw.

author: Berni
author_rank: Super Contributor
timestamp: June 25, 2021, 01:59:57 pm
content: Quote from: RoGeorge on June 24, 2021, 04:43:00 pmThe DP832 is a bit on the deep side but not too bad. Most test equipment for bench use (apart from the most modern ones that moved to the new vertical standing style like scopes) need about 30 to 40 cm of depth. On top of that this form factor has a great benefit of being nicely stackable, sure it might use 2 or 3 times the depth compared to a modern slim standing scope, but can you stack 3 of those scopes on top of each other?Not only is the DP832 in a reasonable depth range for bench gear, it is also 1/2 rack width, so this makes it the same width as a lot of bench gear from HP Keysight, Keithley, Fluke, BK...etc Making it stack on top of it perfectly. I do have a 40cm deep set of shelves behind my bench for this reason.But yeah compared to a cheep little single channel bench PSU the DP832 is not very portable and you would not want to move it too often with how heavy it is. Then again so are all the other 3 channel linear PSUs of a similar power range. So yeah if you are after something you can just easily grab and plonk down on any random bench then you either need a smaller single channel linear PSU or a compact switchmode one.

author: hpw
author_rank: Frequent Contributor
timestamp: June 25, 2021, 05:06:55 pm
content: My fish.... It is heavy, enormous and costs some to ship!. fan as load as a hoverand is constant even on low load. cannot set both as 10.0V one 10.02V, the other always 20mV off even on tracking mode. be careful about the common GND if you have +/- 15V and + 3.3V on third! While made not logically to connection +/- V GND. LAN and one digit more extra bucks. this as DIY project, for this price hard to buildNice tracking mode for the first two as +/- in common. Current is still separatedSo locking how to set the first two with equal output voltage!Overall OK for bucks, consider the GND connection behavior if 3 requires a common groundHp

author: edtyler
author_rank: Contributor
timestamp: June 27, 2021, 12:17:57 am
content: I have had the DP832 for over 2 years and it has been quite useful and reliable. It is used to source 48V at 2.5A and also 14.6V at 6A.It is much more useful than single output supplies, of which I have at least 4. The fan noise is noticeable at full output, but less so at lower loads. Overall, a good value for the money. I would buy it again as a general bench supply.The power on spike issue exists with many linear supplies, including those from HP and Lambda. I was trained to never have any sensitive loads connected when the power supply is turned on or off.So far, I've only run across one bug that is annoying enough to mention: If one has CH1 and CH2 operating in parallel with a monitor condition on both channels set to turn off that channel when the current drops below a specified value. The logging for that channel shows the drop to the cut off current value and then, instead of showing zero amps for the rest of the log, it shows a ramp up to about 0.7A and remains there indefinitely. This is not a big problem because the deflection point is easily spotted. It does interfere with getting statistics (watts) on that channel unless one sets the ending sample number at the deflection point, which is easy to do.

author: bson
author_rank: Unknown
timestamp: June 28, 2021, 07:11:48 am
content: The Rigol is a fine PSU, if a little big for what it does. But any smaller comparable 3-channel supply like the Keithley 2231A-30-3 is going to cost more. And the DP832 is still feature-rich, for example it has LAN and a sense input. (Though annoyingly the sense input in the back, using a special connector that is guaranteed to get lost.) If you have a decent remote controlled Agilent 34401 compatible DMM it's also easy to calibrate yourself.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 28, 2021, 07:19:31 am
content: Quote from: bson on June 28, 2021, 07:11:48 amDP832 doesn't have sense inputs.The green connector in the back (its pair is delivered together with the DP832) has only digital inputs and outputs. Those digital I/O pins are programmable and can do a couple of things described in the manual. They are especially useful for automating testing, to trigger the source externally or alike.

author: bson
author_rank: Unknown
timestamp: June 28, 2021, 07:53:04 am
content: Hmm. I remember wrong then.Edit: confused it with my Keysight 66312A.

author: Berni
author_rank: Super Contributor
timestamp: June 28, 2021, 11:03:10 am
content: Yeah DP832 has no external sense inputs. They are internally wired to the banana terminals.But then again i never really used sense inputs on a general purpose bench PSU. These 3A that it can supply is still such a low current that simply using cables with a decent amount of copper in them (lots of mine are 1.5mm2) makes the voltage drop almost non existent.Most of the times i actually used remote voltage sensing is for stuff involving very large currents >20A where even a big fat hose of a cable can have a considerable voltage drop. Almost all gear that works with those sort of currents has a remote sense in some shape or form. Quite often seen in the form of one of those green screw terminal connectors.Especially on PSUs with a lot of channels having separate sense terminals can really clutter up the front panel, tho it admittedly also makes the PSU also look more impressive (even if you rarely even use them)

author: hpw
author_rank: Frequent Contributor
timestamp: June 29, 2021, 05:54:10 pm
content: So I went to Manual Calibration andVDAC and channel 1 / 2 / 3 mysteries!Just enter into the util, page 2 for manual calibration menu and please may tell about similar behaviors.While you may go to each level steps and save it, but will never show up your entered values in case on a second checkup!VDAC Channel 1: 0.45V and measured 152mV 2.0V and measured 1.685VVDAC Channel 2: 0.53V and measured-254mV 0.73V and measured-0.0522mV 1.55V and measured0.779mV 2.7V and measured1.931V 3.68V and measured2.909VVDAC Channel 3: 0.12V and measured 104mV 1.05V and measured 1.033VThis means Channel 2 is ways off to the given referenceseven negative!!!How to proceed with calibration download on RIGOL & calibration the related manual (to enter default PW:2012)Was just a trial to get ride 20mV offset of the tracked CH1 & Ch2 channelsHp

author: hpw
author_rank: Frequent Contributor
timestamp: June 29, 2021, 05:56:36 pm
content: Here more about other already known issues:https://www.eevblog.com/forum/blog/eevblog-549-rigol-dp832-lab-power-supply-followup/

author: thm_w
author_rank: Super Contributor
timestamp: June 29, 2021, 09:27:58 pm
content: Quote from: hpw on June 29, 2021, 05:54:10 pmNever do manual cal. There are automated python cal scripts here that will: be more accurate in the end, and less hassle to complete. Best if you have a USB/networked DMM.https://www.eevblog.com/forum/testgear/dp832-calibration-using-python-pycharm-running-on-windows/If its close enough already just leave it though.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 29, 2021, 09:35:31 pm
content: The one in the video is caused by the voltage drop on the internal wires. Can be fixed by a thick bridge between the GND of the channels 2 and 3. Ideally the bridge would be a thick copper wire soldered between the two GND connectors internally, but can be as well an external bridge between the two GND banana plug.That's more like a theoretical corner case. In real life you would see more errors caused by real wires going to real circuits, so yeah, could have been better but doesn't really matter.About calibration, I think that is supposed to be made in an automated way, it would take a lot of time and patience, and be very prone to errors to calibrate manually. AFAIK there are over 400 points to measure, read, then introduce manually- 48 measurement points for CH1 VDAC- 48 measurement points for CH1 VADC- 32 measurement points for CH1 IDAC- 32 measurement points for CH1 IADC- same for CH2- same for CH3 except VDAC and VADC are only 18 measurements each instead of 48On the CD that came with DP832 there is a "DP80_CaligrationGuide_EN.pdf" that says it is recommended to calibrate once a year but they also wrote:QuoteAs a side note, my DP832 have some small errors, but I never calibrated it because it doesn't matter for my needs, and wires will introduce more errors anyway. Also I'm not very sure about the correct calibration procedure, and how big exactly is the calibration table (how many calibration points are), I've seen contradictory info floating around. In the programming manual there are no calibration commands, but from the disassembled firmware by tv84 there are hidden SCPI commands for DP800 calibration:Code::CALibration:SET:CALibration:MEAS:CALibration:STORe:CALibration:CLEar:CALibration:STARt:CALibration:END:CALibration:SENSE:PROJect:CALIbration:DATA:VOLTage:WRITe:PROJect:CALIbration:DATA:VOLTage:READ?:PROJect:CALIbration:DATA:CURRent:WRITe:PROJect:CALIbration:DATA:CURRent:READ?:PROJect:CALIbration:DATA:CURRent:ADDRess?:PROJect:CALIbration:INFO:WRITe:PROJect:CALIbration:INFO:READ?:PROJect:CALIbration:INFO:ADDRess?

author: thm_w
author_rank: Super Contributor
timestamp: June 29, 2021, 10:55:16 pm
content: Quote from: RoGeorge on June 29, 2021, 09:35:31 pmSee thread above, the procedure is almost completely automated.The number of cal points varies depending on the supply, for channel 1 and 2 around 43-46 points.The maximum the table can hold is at least80 points.

author: spiff72
author_rank: Regular Contributor
timestamp: October 08, 2021, 06:28:44 pm
content: I was looking at a used DP832 which is claimed to be lightly used and purchased new about 3 years ago. Is there any way to identify if it is a newer version with the revised heatsink? The serial number is visible in the listing...Otherwise I saw mention of the heatisink being visible from outside (through the vent)? Is there an easy way to determine this based on a photo of this vent? (Heatsink color for example?)Also, I have seen that there may have been some added caps to fix the noisy 4.2V rail on the back of the control board. Is it known whether these fixes were implemented at the same time as the heatsink change?

author: Berni
author_rank: Super Contributor
timestamp: October 09, 2021, 08:44:24 am
content: Well mine is fine and has serial number DP8C155202659 if that helpsTho it is not hard to fix yourself as its just as 5V regulator. And you may want to take it apart anyway since the stock fans are pretty loud and can be plenty improved with better fans.