Rigol DMM DM858 comparison thread - Page 1
Forum section: electronics / testgear

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: March 28, 2024, 03:43:55 am
content: Recently, Rigol released a new DMM series, the DM858E and DM858 models. Both of them are 5-1/2 digit DMMs. As they already have 5-1/2 and 6-1/2 digit offerings, I thought I'd be interesting to compare these to each other and to other DMMs on the market.The differences between the E and non-E model are that the E model has 0.06% vs 0.03% DCV accuracy, can store only 20K readings vs. 500K, and does 80 readings a second vs. 125 readings a second. Additionally, the E model lacks the 10A input jack. It can only measure up to 3A. They retail for $370 and $500 USD, respectively.It should be noted that I'm including the Keithley just to give you an idea as to what a really powerful DMM in capable of. I converted the PPM readings to the typical XX% + YY% (reading + range).FLIR DM93*DM858`DM3058DM3068Keithley 2001^DCV0.05 + 1d0.03 + 0.0040.015 + 0.003-40.0035-55 + 0.0005-100.0024-41 + 0.0002DCA0.2 + 2d-10d0.055-0.250 + 0.005-200.055-0.250 + 0.005-200.007-0.1+0.002-200.04-9 + 0.0020-25ACV (50-60Hz)0.5 + 2d0.2 + 0.10.2 + 0.050.06-8 + 0.03-40.1-0.07 + 0.015ACA1 + 2d0.05-3.00 + 0.02-50.3-5 + 0.1-20.10-15 + 0.04-60.20-15 + 0.015Ω0.2-2.0 + 1d-20d0.05-3.00 + 0.02-150.02-25 + 0.003-50.01-4 + 0.001-40.005-4.000 + 0.0004-0.1The overall conclusion I can draw is that you should buy the DM3058 over the DM858. The E model and a good handheld DMM are kind of a toss up. The DM858E is better at ACV, but worse DCV accuracy, and the shunts for both DCA and ACA are rather restricting.Well, I hope you enjoyed the write up. What are your thoughts?* This is the DM93 original. They have since released a DM93-2 with worse accuracy. Oddly enough, it's also bigger and heavier. These counts are for the 3-3/4 range, not the full 4-3/4 range as it's accuracy specs are not listed in the datasheet/manual. I could have chosen a Fluke 287 for this chart, but the accuracy of that meter is largely worse than the DM93.^ Yes, the resistance accuracy really does drop off for the Keithley 2001/2, but then the range at that level is 1Gohm; which is well above what the other DMMs can do.` It should be noted that the burden voltage of this DMM is well above the average 100ohms. The DM858 uses a 330ohm shunt for the 100uA-1mA range, a 3.3ohm shunt for the 10-100mA range, and a 0.008ohm shunt for the 1-10A range. What good is accuracy if the burden voltage is over 3x other meters?

author: bdunham7
author_rank: Super Contributor
timestamp: March 28, 2024, 04:09:10 am
content: I doubt anyone is buying these for their accuracy. There are plenty of other reasons to have a bench meter.As for specs, they're barely competitive with good handhelds including some that are half the price (BM869S, 121GW) and I suspect there are issues even meeting what they've listed. b/t/w, how do you calculate the DM93 has better specs than a 287 with 0.025% basic accuracy?

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 28, 2024, 05:33:45 am
content: There is better than this, the RMS is only up to 8kHz.Others would not buy this because of its accuracy.If an advanced loop record function is included, and the basic functions are developed and refined, more people would buy it.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 28, 2024, 10:52:41 am
content: The meters has the rather large memory for logging data and the big scree may also be a bonus - especially if if supports using the full screen for really large digits. This could be a thing for educational use (demonstration experiments). The limited AC bandwidth is indeed a bit disappointing.Compared to a handheld meter one gets main supply (can be a bonus, but not always), the graphics features (no idea how useful) and 4 wire ohm function.As a somewhat comparable meter I would look at the Sigilent SDM3055, or for the form factor maybe the Keysight EDU34450.

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 28, 2024, 02:37:14 pm
content: The record function does not work yet. Or at least I can't find it where it should be according to the manual.This can be used from a power bank, but who would run around with such a large device when there are much more suitable ones.For Display/BarChart, the update speed is the same as the speed of updating the displayed number.If I set the refresh rate to Slow, the Bar's speed also slows down. Here, I expected that 125read/sec would be the constant speed of the Bar.I couldn't find an option to display the numbers in full screen. The largest number size is ~1.2x2.5 cm.Some people are bothered by the appearance of the number, recalling the previous posts. Not customizable.It also shows that the release was rushed, it is good for basic measurements, it has a few extra things compared to a simple multimeter, but there is something that is essential but is missing.

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: March 28, 2024, 03:26:21 pm
content: Quote from: bdunham7 on March 28, 2024, 04:09:10 amAfter comparing it to other offerings, I am a bit confused as to why people would want it. It's only redeeming feature is the somewhat lower price than good handhelds.Quote from: bdunham7 on March 28, 2024, 04:09:10 amI wasn't really trying to hit against the fluke. The main differences are the amount of digits you have to add to the meters. This throws off the accuracy when measuring lower signals... Wait, the Flir has a little note on the bottom of the tables telling us to add 10 to the digits when below 10% of the range in voltage and amperage mode and add an additional 10 when below 5% of the amperage range. Ugh. These little gotchas. I should have just gone with the Fluke, it's more straight forward.

author: J-R
author_rank: Super Contributor
timestamp: March 28, 2024, 06:37:30 pm
content: I think for new hobbyists on a budget that want something powered up on their bench all day, the Rigol DM858E and Siglent SDM3045X seem reasonable for the price. Valuable UI features leveraging the large color screens, as well as USB and Ethernet built in. As mentioned, accuracy is probably not their primary focus.Once you go past that that price point though, I could see the desire for something better, at which point you may need to combine them with computer control/UI to take up the "slack".Honestly, I am not sure how to predict what the top brands will offer in the next decade with regard to their bench equipment. Will they all move to huge touch screens with fancy GUIs? Or continue to push for users to leverage computer software? Scopes from the big players seem to already be firmly on this road of large touchscreens, but not sure about DMMs, power supplies, etc.

author: MarcelMo
author_rank: Newbie
timestamp: March 29, 2024, 05:02:20 pm
content: I have bought 2 weeks ago the new Rigol DM858E. I do like it due to the new formfactor - big screen etc. I tested some functions the last week, but today - accidently - i was playing with my (also) new Power Supply. What I noticed is that the DMM is not reacting correctly in the DCV 28...50V range. Situation is as follow : DM858E is not connected yet. So it floating in the mV range (AUTO setting). The Power supply is outputting 33Volt. Then I connect the DMM 858E. to the power supply outlet. The DMM showed still some low values in the mV range and is also drawing 26mA.Unbelievable. I made I video about it. Nothing fancy what I did. Anyone some experience with this DMM? SeeI have already complained to my supplier - wondering what Rigol will say about it. Maybe I have no luck and the problem is only on this specific device (or it is a general problem)

author: Kleinstein
author_rank: Super Contributor
timestamp: March 29, 2024, 05:57:48 pm
content: This really a nasty type of failure.I noticed that with increasing voltage above 40 V the current when down. Still 40 V and some 25 mA are still 1 W. So something in the protection part of the DM858 will dissipate quite some power.There may be something like a low voltage spark gap to protect the 100 mV and 1 V ranges. Once it triggers the voltage may be too low to still detect an overload. This could be hardware failure with a series MOV shorted. An alternative scenario could be an input amplifier / switch going to a latchup mode and this way shorting the input instead of just clamping.The 50-100 mV in the initial test with 33 V looks quite low - less than I would expect for the burn voltage of a sparc gap.There is a chance that this is a hardware fault and other units may not show a similar error.

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 29, 2024, 05:58:04 pm
content: Quote from: MarcelMo on March 29, 2024, 05:02:20 pmI also have the bug. DM858For me, between 28V-36V.I was able to test it up to 60V.If I plug the test lead in the opposite direction, I don't experience the error.In other words, I measure negative voltage with it.If the Range selector is not in AUTO mode, it measures the voltage well.It's like for some reason the AUTO mode doesn't work for me between +26-36V. For you, between +28-50V.I am using the latest firmware.v00.01.00.00.20 2024-03-27I tested it this morning.It did not work properly between 30V-40V.I tested a couple of power supplies connected in series up to 120V DC, increasing by 1 Volt, it worked. It is still good after swapping the two test leads.Then I tested the mV range. It still measures well.

author: JCS666
author_rank: Contributor
timestamp: March 30, 2024, 05:22:32 pm
content: More problems, math and auto mode don't workIt also does not maintain date and time after turning off

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 30, 2024, 07:31:48 pm
content: Quote from: JCS666 on March 30, 2024, 05:22:32 pmMath only work in manual mode not auto!It keeps the date even after I turn it off.If you mean to set the time to be visible, then restart it and then not see it, then in the settings "Load Last" must be changed to "Last". Unfortunately, the factory settings default to Hide a Display time...

author: coromonadalix
author_rank: Super Contributor
timestamp: March 30, 2024, 10:39:22 pm
content: erk seeing this behavior tell medo not buy thisuntil the FW is iron-ed outa lack of check ups from RigolDamn ... I totally hate the zero leading digits, this is the thing i hated from the 34401a and upFor the size of this meter, while i do see the frame size, and not deep, since its a scope casing adapted to a meter,i'm not impressed so far if the digit have these cross lines in themwtf ? did they tried to imitate and VFD grid?haven't seen any tear down of this meter ??https://www.eevblog.com/forum/testgear/rigol-just-launch-its-new-function-generator-dg800pro-900pro/75/ok and once again, a case dismantling if the fuse blows out ...

author: shapirus
author_rank: Super Contributor
timestamp: March 31, 2024, 12:04:03 am
content: Quote from: coromonadalix on March 30, 2024, 10:39:22 pmThis whole new series of equipment is somewhat... undercooked, I would say. The scope is almost fine: it's inexpensive, it's hackable, it has good hardware (except the damn fan!), and its bugs and UI missing features/weird design choices are tolerable, because they don't defeat the purpose and are, generally, minor.The DMM, however, seems to be a different story. It's not inexpensive for what it is, its specs are mediocre, and on top of that there are silly and immediately obvious bugs which should have never made it into the final product. Yet another evidence that there is apparently no QA team whatsoever at Rigol, or if there is one, then its work is disregarded and a sooner release is preferred over quality. That wouldn't be a big issue if Rigol collected relevant information about bugs (this forum alone has a vast knowledgebase on them) and published post-release bugfixes in a timely manner, but it does not seem to happen.I'm not looking to buy a bench DMM (hope so), but if I were, I wouldn't be considering the DM858, not least because I own a DHO800 scope and wouldn't want to have another product engineered with the same attitude.Quote from: coromonadalix on March 30, 2024, 10:39:22 pmlol.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: March 31, 2024, 12:41:28 am
content: Quote from: coromonadalix on March 30, 2024, 10:39:22 pmWhy do you think it's a scope casing adopted for a meter..that they release 3 products over ½ year, doesn't say anything about what a given case was intended for.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 31, 2024, 12:43:58 am
content: i think the dmm chip seems to be some Hycon or Fortune ... the main cpu is an allwinner A40 SOM, so for sure it must run some nix OS ....Ok touch screen and some functionalities could be good, but it suck so much just seeing it working on YoutubeI trust more the 344xx series than this puppy, even the Owon 55k count meter based on a Hycon too loll, at least the bugs are known on the Owon ??yeah Rigol smell like toys ... Sorry Rigol "up your game" a bit please

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 31, 2024, 05:53:59 am
content: Quote from: coromonadalix on March 31, 2024, 12:43:58 amYeah, I'm starting to feel the same way.The DM858 did not meet my expectations.Weak DMM, few features.It's not worth buying in its current state.Rigol would have to make a huge improvement to change my opinion.It doesn't know much for its price, I would have been better off with a Brymen.I'm starting to get the feeling that the bug above is going to be a hardware issue.When cold, it is between 31V-41V, after warming up it is between 28V-36V. So don't take it apart, the warranty will still come in handy.I wonder if the big fuse somehow blows, then how do we replace it without losing the warranty?

author: J-R
author_rank: Super Contributor
timestamp: March 31, 2024, 07:39:50 am
content: This does not surprise me, bugs are Rigol's calling card. I would expect them to address something this serious with an update or warranty service.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 31, 2024, 02:36:08 pm
content: .................... So don't take it apart, the warranty will still come in handy.I wonder if the big fuse somehow blows, then how do we replace it without losing the warranty?For this problem, i force the cal center(s) to put sticker on the main casing, ie: not on case screws or 2 parts case joints ..... i'm sick to break a seal because of a damn blown fuse(s)

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 31, 2024, 03:16:08 pm
content: They didn't make a small door on the back for that fuse out of laziness or sloppiness...The warranty sticker sucks, there's a plastic film on the top and some silvery stuff on the bottom, you can't pick it up in one piece, something like what's on a scratch card.

author: bdunham7
author_rank: Super Contributor
timestamp: March 31, 2024, 03:27:10 pm
content: Quote from: csuhi17 on March 31, 2024, 05:53:59 amI'm guessing the front end is badly misdesigned and a clamp is drawing down the voltage before the autoranging can range up. In addition, the clamp must be in a place that only the 1K surge resistor (or whatever they use) is between in and the input, thus the tens of milliamps of current draw. There will be pressure to come up with a software fix for this and that will probably be ugly. One heck of a product launch, Rigol!

author: shapirus
author_rank: Super Contributor
timestamp: March 31, 2024, 03:47:04 pm
content: Quote from: csuhi17 on March 31, 2024, 03:16:08 pmA soldering hot air gun (on the lowest temp setting and with great care) worked well on the sticker that was on my DHO804. Don't tell anyone.(that sticker is really fragile though, that's true).

author: coromonadalix
author_rank: Super Contributor
timestamp: March 31, 2024, 04:14:03 pm
content: they could added an banana jack with an integrated fuse we can see on reputable brand loll but cost ....i would check the pinouts of the dmm chip to see and try to guess witch model it is .... since it seem to be buffered on top ....it is not a very precise meter for sure, nor a fast one ??when i start an 34410a, it is ready to measure, for sure letting it warm up is better, but i don't wait after an NIX os to boot up ... nor some WinCE based ones tooSure people may like all other related features, but at the moment Rigol need to redo some work and address the comments we make here

author: DaneLaw
author_rank: Frequent Contributor
timestamp: March 31, 2024, 04:54:54 pm
content: Quote from: csuhi17 on March 31, 2024, 03:16:08 pmThese silvery warranty sticker,s will saturate into a "breach" visual layer, the moment you try to peel it off.Though I doubt you would be out of warranty breaching it, but it likely also comes down to where you purchased it.From Europe.. peel away, slice cut it, lay a dump on that sticker, and you' will still have the warranty.If you still wanna peel it without visual indication. the best approach is alcohol to get the adhesive to take a rest.

author: csuhi17
author_rank: Frequent Contributor
timestamp: March 31, 2024, 05:19:15 pm
content: I ordered the DHO924S from China on aliexpress, which means the warranty is almost 0.If I had ordered it within the EU, I think I would have sent it back and ordered a Siglent.The DM858 and DG912Pro are both from Batronix.The sticker for DHO fell off by accident, and with the other two I was already very curious if it was worth buying the more expensive version.How to properly hack the DG800pro or, in the worst case, the DG902pro to the level of the DG922pro.I hope they don't have a physical problem, only software problems, and I hope Rigol fixes it quickly.

author: MarcelMo
author_rank: Newbie
timestamp: March 31, 2024, 09:30:38 pm
content: Thanks for testing this. I assume the Front End of a 858 or 858E will be the same. I noticed also some different behavior, depending on how long the DMM is already switched on (=warm).I my video the turning point of correct DMM reading was about 50 Volt. But today I have managed to have it even on 60 Volt.I seems to be, that if you increase the voltage very slowly, you might end up also with those higher DC values.Also I confirmed that the problem doesn't appear if you already in the 100V setting (no AUTO), then everything works well.I was just thinking : As the 100mV and 1V ranges have in the non-AUTO setting an impedance configuration option (via Measure) of 11.2M Ohm or 10G ohm. So I was wondering if this HW design might influence the current DCV Auto problem?Or may be better: could the Analogue Front End designed in the different way for those small ranges and the overload protection mechanism is not designed correctly for it. (Just guessing). It would be not nice if the HW needs to be replaced.Anyway, I was hoping that I was the only one with this DCV bug.But that is not case.... Again thanks for testing!!

author: bdunham7
author_rank: Super Contributor
timestamp: April 01, 2024, 02:20:11 am
content: Quote from: MarcelMo on March 31, 2024, 09:30:38 pmThe input impedance cannot be selected in when autoranging is active? Which impedance is it then at low voltage levels when autoranging?

author: csuhi17
author_rank: Frequent Contributor
timestamp: April 01, 2024, 04:40:06 am
content: Quote from: bdunham7 on April 01, 2024, 02:20:11 amIt allows you to change it only in the measurement range of 100mV ls 1V, by default 11.2M.11.2M in auto mode, measured with another multimeter, 10M.

author: Kleinstein
author_rank: Super Contributor
timestamp: April 01, 2024, 07:59:11 am
content: The problem seems to be the way the 100 mV and 1 V range handle overload. This has 2 problems:1) the input current gets quite high. 25 mA is really quite a lot and could even cause hardware damage from overheating from long time overload.2) The meter does not dedect the overload condition and reads a low voltage instead. It thus does not switch to a higher range and autoranging is not working.Especially the 1st problem is more like a hardware isssue, not so much a thing that should be handled in software. It would only be a wrong configuration (e.g. relay setting) that could be fixed in SW.So I am afraid a real fix may need a change to the hardware. Normally the protection should be a hardware thing and not rely on the software at all.Getting 25 mA arelady at a relatively low voltage suggest a protection with a PTC. This could also explain the slow / thermal effect when slowly increasing the voltage even more.For only 5 digits the simpler resistor chain protection should be sufficient and the PTC part may be there primarily for the resistance measurements.Having the auto ranging only with the 10 M input impedane mode makes some sense. The 100 mV and 1 V with high impedance modes would likely need an extra relay switching. This complicates the auto ranging.

author: csuhi17
author_rank: Frequent Contributor
timestamp: April 01, 2024, 08:40:35 am
content: I'm testing a little to measure how the voltage measured by Rigol, the voltage added from the power supply, and the current develop.It seems that even after a few seconds the range of this error decreases.For me:At the lowest voltage.28.90V and 25mA from the power supplyDM858 starts at 1.085V and when I leave it on, it starts to drop rapidly.At the highest voltage.32.91V and 33mA from the power supplyThe DM858 measures a slowly decreasing voltage from 87.00mV.If I play with it a lot, the range where it is not good has narrowed.Good little advertisement.(from -1000V to 25V) and (from 50V to 1000V) can be used safely, but between 25V and 50V requires extra attention.Unfortunately, I could only test between -120V and 120V.

author: JCS666
author_rank: Contributor
timestamp: April 03, 2024, 02:52:38 pm
content: Quote from: csuhi17 on March 30, 2024, 07:31:48 pm

author: UFOdriver
author_rank: Newbie
timestamp: April 08, 2024, 08:14:24 am
content: Has anyone already tested the conversion of DM858E to DM858?

author: ass20
author_rank: Regular Contributor
timestamp: April 09, 2024, 10:34:10 pm
content: Can you send it for me, for testing modification ?

author: UFOdriver
author_rank: Newbie
timestamp: April 19, 2024, 08:33:19 pm
content: Not working upgrade from DM858E to DM858

author: JCS666
author_rank: Contributor
timestamp: August 14, 2024, 07:34:46 pm
content: Quote from: MarcelMo on March 29, 2024, 05:02:20 pmThe solution is here:https://bit.ly/DM858Solutions

author: MarcelMo
author_rank: Newbie
timestamp: August 16, 2024, 12:54:03 pm
content: Thanks. It is more or less solved - there is still a temperature dependency and the problem might pop-up again - or at least with my DM858 (which is in repair now).I made an update of the HW failures - where the low impedance topic is the most dangerous one.https://youtu.be/Zf48CLWF1pA

author: alicumircea
author_rank: Newbie
timestamp: October 04, 2024, 08:27:14 am
content: Hi,Sorry for hijacking this thread, but I believe here are persons that know both the dm858 and Agilent 34401a. I am looking into buying a bench top multimeter and initially I was hunting for an Agilent 34401a. I am repairing iPhone boards and I use a multimeter in diode mode for about 90% of the time. I don’t need extreme accuracy, what I need from a dm in diode mode is to beep during probing - a long beep for a short where the reading is below 0.1V and a short beep when the voltage drop is between 0.1V - 1V. Now, I use a Fluke 179 which is perfect for what I’ve described above, BUT…. I am recording YouTube videos with my repairs and I need to display on the screen my DMM readings. Because of this, I moved from the Fluke to a Uni-t 181a that I could write a software for to have it displayed on the screeen. I don’t very much fancy the uni-t as it does not short beep the way I want it.Both Agilent 34401a and new dmm s like the dm858 have the scpi protocol that I can interface with my software. My question is:Does anyone know if the Agilent beeps in diode mode as per my requirements?Also, same question about the dm858 or any of the newer dmm s that I can find as new for a price tag up to 400 eur?Unfortunately I couldn’t find any info related to this as extremely few are using the diode reading.Out of the new DMMs I prefere the Rigol due to its form factor, although I am a huge Agilent fan.I believe the new dmm s are easier to implement in my software. Agilent proves to be a bit more strict with the scpi protocol, for example I have a new Owon P4305 PSU and an old Agilent E3632A. Interfacing Agilent was a struggle compared to the Owon although both use scpi. For example, the Agilent needs to be in remote mode to have a proper output reading which locks the front panel, so to change the voltage for example, need to take it out of remote, adjust from the panel, then place it back to remote.

author: W4HBM
author_rank: Newbie
timestamp: December 16, 2024, 01:25:42 am
content: When conducting a class in EE, especially at the "101" level, the demonstration gear doesn't need to be world-class, just simple enough for young minds to make the connection.Someone here mentioned to me the phrase "burden voltage." In order to arrive at a greater understanding of the micro world mu use of bullet proof VOM's like the Simpson 260/270 series is a wonderful add-in. The phrase used in the past, when DMM's were becoming popular, was "phantom voltages."The Rigol 858's display, while being visible to many around the lab bench, still bobbles, while the 270 analog vane just hangs there, (especially in the dB ranges).What is comforting to know is that Rigol Technical Support will address issues quickly. If their DM858 shows a "legal" amplitude nearing +20dBm and the SpecAn burns up, I know Rigol will go to the "ends of the earth" to make it right, and to discover what the issue truly was.Of course, having an HDMI port to bring it up on the big screen would be excellent, but at the simple price, the '858 is fine the way it is.