Good bench meter for logging \ trending? -Looking at SDM3055, used Keithley, etc - Page 1
Forum section: electronics / testgear

author: Brandon_K
author_rank: Contributor
timestamp: July 02, 2017, 01:26:19 am
content: Hey guys, long time lurker.My job role has recently shifted a bit so I'm in the market for some new gear. Previously I was mostly our road guy doing facility commissioning with some R&D on new products when I had time. Now, I'm mostly doing R&D at our production facility and I'm finding my road tools to be a bit lacking and mostly a pain in the ass on my bench. I have a slew of Fluke meters that I use for testing. My go to is my 289, but the battery life is horrific (thank god for Eneloops!). My 789 is the next to be grabbed, past that I grab one my ancient Keithley 130 or a 87. I'm generally only working with DCV 12-24v and DCI (current is a wide range, anywhere from uA to hundreds of amps. Obviously a clamp meter will be used on anything < 10A).I do a lot of work with batteries where I need to measure charge and discharge, both voltage and current and I need to log them, often over the course of 24-48 hours. My Fluke 289 is pretty good at this. I love that it's on board logging and I can do trends right on the meter. Then I pull it off and compile the software. I like the idea of Fluke Connect, but honestly the app sucks, at least for Android. It won't actually log and the graph / trend resets as soon as the screen turns off. It's completely useless. On the plus note, their app has made me not care about upgrading my 376 to a 376 FC, so the free app saved me a bunch of money! Fluke Forms on the PC is pretty garbage too. I think I'm going to move my road gear over to Keysite. Their U1115A remote display / logger with up to 4 connected meters is AMAZING! I wish that would have been around when I bought my 289! Seeyabye Fluke! Anyhow, I digress.What I need / want;* Dual window / view* Simultaneous measurements (DCI / DCV)* Bench style* 5.5 digits (of course I'll take 6.5)* Trending / logging software that doesn't suck.* Ethernet would be awesome* USB preferred, but RS232 would be fine since it will permanently connect to the meter anyhow.* Ultra fine accuracy is not critical. I work mostly in the 24v world with industrial PLC's, though every now and then I get into 3.3/5v logic. 0.05 is fine (of course I'll take better). Accuracy and resolution of course are two different things.* A decent update rate.* 4 wire preferred* LabView compatible preferred* Somewhat modern. I'm definitely not looking for a manual ranging pushbutton 8050a* I'm brand agnostic and I'm open to used or new* I'm technically a subcontractor and I supply my own gear. Budget under $500.So with that out of the way, I've been looking at used Agilent 34405A, GW Instek, Keithley, etc but it's not always easy to find reviews on some of the models. More importantly, while I can install some of the logging software, it's unusable without a meter connected so I can't form my own opinion on it. Hopefully you guys can offer up some opinions. The GW Instek DMM Viewer, while basic looks like it fits my needs. It doesn't seem to have built in trending or graphing, but I guess as long as it can save to CSV I can do all of that in Excel. Siglent's software, while not very polished, looks absolutely ideal for me. BenchVue DMM is beautiful and I LOVE the tablet viewing / control option, but I'm not willing to spend $300/yr on a subscription for it. Unfortunately, I think that rules Agilent / Keysight out entirely for me, which is a shame because I've found some decent deals on HP / Agilent branded stuff.This will be my first bench DMM, so I'm certainly willing to listen to any other opinions on things.Right now, I'm mostly leaning towards the Siglent SDM3055. It checks every box for me and while it's not Keithley / Agilent Keysight / Rhode / etc etc I'm not sure if I *NEED* what those brands bring to the table. I love the display on it, but the refresh looks really slow. I love that like my Fluke 289 I can do internal logging and trending. The video's I've watched on it are fairly old, so I'm hoping a firmware update may have increased the speed on the display update.My one big question is I've seen a few videos on doing simultaneous measurement and I'm a bit thrown off. On an old Keithley video as well as a ISO-TECH showing dual measurements, it sounds like there is a relay in there clicking? On the Keithley it sounded very fasy, maybe on the order of 50 or 100ms. On the ISO-TECH video it was much slower, maybe on the order of 500 or 700ms. Is that normal for a bench meter? (On second thought, it may have been on the Siglent)Thanks all!

author: Pinkus
author_rank: Frequent Contributor
timestamp: July 02, 2017, 10:21:52 am
content: just two short notes on the Siglent:1) you can speed up the measurement time by setting it tofast- though you are losing accuracy2) V / I isnotsimultaneously but one after the other. As you recognized correctly, a relay will click inside switching constantly between both modes. With this mode you might have two measurements per seconds, not more. While this fine if you want to log something for a few minutes or maybe an hour, I would not recommend this for long time logging, as the relay will wear over the time.Most (>99%) DMMs with dual display mode will switch like this between V and I. All DMMs I have seen, are switching the mode with a relay. It will be difficult to find one without.Another idea: what about a scope? Two channels are fine: one showing voltage, one showing current (either voltage across a 0,1 Ohm resistor or a dedicated current probe).

author: nctnico
author_rank: Super Contributor
timestamp: July 02, 2017, 10:27:46 am
content: I'd get two meters and read them from a self written PC application which dumps the data into a CSV file. Two VC8145 bench meters easely fit the budget. I recommend to get two meters to avoid wearing the relay inside the DMM.

author: TiN
author_rank: Super Contributor
timestamp: July 02, 2017, 10:45:49 am
content: Two classic 34401A's ? I think these are not hard to get for 500$ budget. Perhaps even with some room for decent kelvin probes.

author: alm
author_rank: Super Contributor
timestamp: July 02, 2017, 11:16:54 am
content: I second the two meters and own PC software (should be trivial in Labview). Manufacturers software is usually either crap or expensive (BenchVue).Controlling two RS-232 meters would require two USB-RS232 adapters. My experiences with Windows and multiple USB-RS232 adapters is that Windows likes to shuffle COM ports around whenever things get changed (e.g. different USB port). So you might need to figure out which meter is which in software based on serial number or something if you do not want your setup to be fragile.If you are rolling your own software, them something to consider is from that $500 buying older meters and a GPIB interface (pretty sure you can get some decent USB-GPIB interfaces for under $100, like the Beiming). This allows for cheap DMMs like the HP 3478a and Keithley 199. I believe there are Labview drivers for both. Both DMMs can sometimes be found for under $100 used. Add a few dollars for a GPIB cable, and you could be done well under budget. Current measurement is limited to 3A max. They would have higher update rates (the Keithley 199 can go up to 80 readings/second in 4.5 digit mode) than cheaper meters, 4-wire resistance support and probably better driver support and programming manuals. Of course you will not have any warranty accept possibly DOA (if you buy one advertised as working).Quote from: TiN on July 02, 2017, 10:45:49 amTwo 34401As in working condition for under $500 should be possible in the US, but would max out the budget and still has the issue of two RS-232 devices. Might be the best option if within budget.

author: plesa
author_rank: Frequent Contributor
timestamp: July 02, 2017, 03:52:23 pm
content: For $500 you can buy 34970A, which is MUX with 34401A, or 34972A which is MUXed 34410A. Just be careful with MUX card type. You do not need to rely on BenchVue, the free Agilent alternative is called BenchLink.Quite cheap is 3457A with MUX card.

author: alm
author_rank: Super Contributor
timestamp: July 02, 2017, 07:10:44 pm
content: I would be worried about the mux relays wearing out if logging at a high sample rate for long stretch of time (which is suggested by the comments about a decent update rate). Logging every few seconds for 24-48 hours translate to a lot of relay wear.

author: tautech
author_rank: Super Contributor
timestamp: July 03, 2017, 08:11:43 am
content: Quote from: Brandon_K on July 02, 2017, 01:26:19 amMaybe the recently released optional new scanner card that features 12 multi-purpose + 4 current channels could tempt you further.http://siglentamerica.com/prodcut-fjxx.aspx?fjid=5378&id=176&tid=37&T=2It's a factory installed option and listed for 3045X, 3055 and 3065X

author: HighVoltage
author_rank: Super Contributor
timestamp: July 03, 2017, 10:27:31 am
content: Also, take a look at the Keysight U127xA series or U125xB series in connection with a U1117A Bluetooth adapter. Free software is available for Android, IOS and PC and works pretty well.I know, it is not a bench meter as you have been asking for but it works so well, that it is a viable alternative.Otherwise, as suggested before, get two 34401A DMMs and it will work perfectly for you.

author: nctnico
author_rank: Super Contributor
timestamp: July 03, 2017, 02:17:15 pm
content: A handheld will typically power off automatically and battery life is limited so I strongly doubt it will be very suitable for logging over a period of 24 to 48 hours.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 03, 2017, 03:11:42 pm
content: Quote from: nctnico on July 03, 2017, 02:17:15 pmBattery life might be a problem, but new batteries should last 48 hours on the U1272A DMM and the Bluetooth adapter. But, these Keysight DMM with logging abilities do not power off automatically, when in remote logging mode. It works actually well on the PC.The iPad might be a challenge for 48h.

author: Macbeth
author_rank: Super Contributor
timestamp: July 03, 2017, 06:32:49 pm
content: The 5.5 digit Rigol DM3058(E) will support dual display volts and current without switching relays. However for logging data, the internal log to memory will only record the main display, not the secondary. Also the internal display options are a table and a histogram, there is no nice measurements over time graph.For logging to a PC using SCPI it will cause relay clicking if you switch between the normally used :MEAS:VOLT:DC? and :MEAS:CURR:DC? commands for example. To do it without the relay is easy enough:e.g. Initialise main display to VDC and then enable dual display mode with DCI:CMDSET RIGOL:FUNC:VOLT:DC:FUNC2:CURR:DCNow in a loop you can read volts with:FUNC2:VALUE1?and current with:FUNC2:VALUE2?and log to your CSV or Excel.The above will not work on the 6.5 digit DM3068 as it only supports AC frequency measurement on its secondary display.

author: Eric_S
author_rank: Regular Contributor
timestamp: July 03, 2017, 08:02:00 pm
content: How often do you need to sample, Brandon_K?

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 03:11:50 am
content: Wow, thank you to every one has responded. It's unfortunate that we have seemingly better feature sets in $300 handhelds than $800 (import model) bench tops.Quote from: Pinkus on July 02, 2017, 10:21:52 amI've read that newer firmware has fixed the issue, but I've not seen it with my own eyes. Every review video that I've seen is a year+ old and they are all to my knowledge running the old firmware. I don't think anyone has done an update video with the newer firmware versions to my knowledge. I'm pretty sure I've now watched every SDM30xx(x) video on YouTube.QuoteYup, that's a deal killer for me unfortunately. Lately my work has been in LiFePo4 and LiCo batteries and that has entailed logging over a ~48 hour period. Generally I'm taking 4 measurements; current and voltage before the PCM as well as current and voltage after the PCM (to the load). As with most Li chemistry cells, they have a VERY rapid fall off, which my Fluke 289 handles really well. I set it to 1 minute and I'm good. Internally, the Fluke will also automatically log any change over 1%, so for the first ~36 hours it's only logging once every minute. When the cells start to roll off, the Fluke picks it up and puts it in the trend chart. I can then export out if I need to, through their horrific software and interface.As for using a scope, I honestly know next to nothing about scopes and what I would need. I've recently started doing some learning about them and I understand a few aspects of the specs, but not enough to make an educated buying choice. As I said in my previous post, I need to log in the ~5-30vdc realm and currents up to ~10A. I know a scope will need a hall transducer, which I've actually already ordered last night for a different use (that is to log current's >10A with my Fluke (and soon to be here Agilent handheld)If you have any recommendations on a 4ch scope that can do datalogging (to a PC is fine, but being able to capture ~10 minutes of buffer for on-instrument reference would be better) so I can measure 2 channels of current and 2 channels of voltage, I'm all ears. I understand channels, some of the interface things (Dave is SUPER helpful for being so blunt on UI things), but I don't understand bandwidth and why I would want / need a 200MHz scope over a 50MHz. I understand bandwidth by definition, but I don't understand how it applies to a scope. A quick google shows me a inexpensive 4 channel scope is a Rigol DS1054Z. It certainly fits my budget.

author: tautech
author_rank: Super Contributor
timestamp: July 05, 2017, 03:32:28 am
content: Quote from: Brandon_K on July 05, 2017, 03:11:50 amHave you seen this one:Scott (Defpom) will get my unit back in a week or two and have a look at the scanner card that was not installed when he had it before.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 03:41:57 am
content: Quote from: nctnico on July 02, 2017, 10:27:46 amQuoteQuoteA stack of meters, while certainly not preferred, may be one of the few options if the scope idea doesn't work out. I've found a Keithley 2790 locally (Source Meter, but it has a integrated 6.5 digit DMM just like their) that I've put an offer on, as well as a Instek GDM-8251A. Both for very good, well below ebay prices. For the time being I'm going to keep my eye out for a used Siglent meter as I really want the onboard trending and logging, I'll likely end up using that as my main go-to every day meter. I just missed a SDM3055 for $300 (used). Doh! They all do RS232, so I'll likely just plug them in to a RS232 ethernet server so they can live happily on my network and I won't have to deal with reassigning COM ports every day.QuoteQuoteI agree, outside of the relay wear, I don't want to deal with noise.

author: alm
author_rank: Super Contributor
timestamp: July 05, 2017, 03:43:38 am
content: Quote from: Brandon_K on July 05, 2017, 03:11:50 amBandwidth is relevant for the highest frequency you can resolve and for the fastest transition times (for digital signals) you can resolve. None of which seems at all relevant for your application. I am not sure a scope is that good a fit for your application. Sure you can get affordable scopes with up to four channels, but they are generally made for acquiring a batch of data, transferring that, and then starting a new acquisition. There is some discussion about sampling for long times inthis thread. However, keep in mind that a scope is generally limited to an 8-bit resolution, and do not expect the effective number of bits to be anywhere close to that number. You may be able to get some improvement by averaging, but it will never be a precision low frequency instrument. So you will lose a lot of resolution and accuracy relative to a DMM, especially since you were talking about 5.5 digit minimum. Also most scopes have a shared ground connection between all channels. That may be annoying if you are ever measuring multiple cells in series, or if you are doing current sensing with a shunt.To me the best solution seems either four DMMs (where you can either go for the cheapest bottom of the barrel new ones or the old ones I suggested that can only do GPIB) or a four channel DAQ. Depending on the voltage range you need, something likethisorthiscould do the job (should definitely be much higher resolution and accuracy than a scope, and much cheaper). I have not used them myself, but I have considered them in the past. There are other similar solutions out there. Unlike a scope, they have differential inputs. But they are less a finished instrument than a DMM. No internal current ranges. Will not measure resistance without external current source. Accuracy out of the box will be worse. Not sure about calibration.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 03:44:45 am
content: Quote from: HighVoltage on July 03, 2017, 10:27:31 amI'm actually already doing this for my road tools. I recently came across the U1115A which allows remote connection and logging from 4 meters. Amazing! I have a feeling my Fluke's are going to be relegated to garage use. Though, Keysight wants absolutely insane prices for their clamp meters. I've ordered a pair of current transducer clamps for the time being to handle clamp measurements.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 03:48:09 am
content: Quote from: Eric_S on July 03, 2017, 08:02:00 pm1 minute or less. Fluke handles this well by default. I set it to log every one minute, but it also automatically logs anything within a 1% difference. I've found a LOT of faults (industrial setting dealing with incoming service) with this. When I can spit out a report, showing it repeating at X time every day and hand that to a lineman, it quickly gets escalated to engineering and fixed.

author: Macbeth
author_rank: Super Contributor
timestamp: July 05, 2017, 04:03:52 am
content: I don't know of any scope that logs 48 hours and does current measurements without an expensive add on probe.I have also stated that a Rigol DM3058E can do exactly what is called for with no relay switching whatsoever. Of course this is to a PC (or Raspberry Pi) and I gave the SCPI commands needed.You just need a USB lead and something like Excel and the free Keysight Command Expert for dummies (you do NOT need Benchvue!), or just code VISA stuff in VB or Python, or go the NI-VISA LabView route and you are sorted.Oh yes, DM3058E does do 10 amps - a lot of bench DMM's only do 3A or so...

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 04:06:41 am
content: Quote from: nctnico on July 03, 2017, 02:17:15 pmQuoteMy Fluke goes into a low power mode when logging. The display shuts off and the power LED blinks every few seconds to show that it's logging. You can press any button to wake the display up to see what is going on. It's well implemented. Even the battery hog 289 will last me a solid 7 days of use on six Eneloops, logging non stop say half of those days. Alkalines might last a little longer, but I can't afford that kind of battery supply.I have a 1252B coming to try out, so I'm interested to see how that handles logging to my phone (or most likely, my Galaxy Tab Pro tablet). Fluke Connect is HORRIBLE at logging, to the point that it doesn't really log. It will do a trend chart, but as soon as the screen shuts off on the tablet or phone, it clears it's readings. From playing with the app on my phone, I think Keysight handles this much better (and is the prime reason I'm likely switching to them for my road case). As long as it goes well, I'll pick up a few more of the 1252B's as well as a 1282A to fully replace my 289.

author: billfernandez
author_rank: Regular Contributor
timestamp: July 05, 2017, 04:49:38 am
content: Brandon: It's kind of an oddball, but the Mooshimeter might be worth a look. For $125 you get simultaneous, long-term, dual-channel data logging, via a 24bit DAC (they estimate about 5 digits of practical precision), to a CSV file on a 32GB Micro SD card.https://moosh.im/mooshimeter/https://moosh.im/mooshimeter/specs/

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 05:11:12 am
content: Quote from: Macbeth on July 05, 2017, 04:03:52 amIs there a reason why I can't use a "standard" hall effect DC current clamp? I looked at some pricing from the big names and the pricing is insane! $2500 for a current clamp?!? That's high even by Fluke standards. I just ordered one that is 1mV/100mA or 1mV/1A selectable (pretty standard on these types of clamps designed to be used on a handheld DMM) for $60. Annoyingly for the purpose I bought it for, it has a BNC connector. But, that should work with a scope, no? mV is mV? As far as logging goes, if it can spit out ASCII, I can log that in realtime into Excel via a few programs that I have written for that purpose. Dave says Rigol's software is crap, but maybe it's good enough for my uses just to retain data. No RS232 or GPIB on that Rigol scope, only ethernet and USB, so I'm not quite sure how I can interface with that.As far as the Rigol DM3058E, yes I saw that, but there are a few things that I don't like about it. Notably that it doesn't log the second channel. If I have to go to an "outboard" logging solution, I might as well just stick with what I'm starting with and that is a bunch of older, inexpensive meters stacked on top of each other. Dollar for dollar, the Siglent has a nicer feature set.All of that said, if the 16 channel card that tautech posted about is not ludicrous on price, I'm pretty sure that will firmly cement me into camp Siglent, IF the meter can log the readings from the card. I REALLY love the interface on the Siglnet's for day to day use. I can build a breakout panel to give me a few extra volt inputs and current inputs from the scanner board and I think I'm pretty much set. Data logging for days!!!! I'm going to contact my local Siglent distributor tomorrow to see if I can purchase the SC1016 separately instead of factory installed, then I can keep my eye out for a good deal on a used 3055, 3045X or 3065X. It seems as though for my data acquisition and multimeter needs, this would be the ideal solution, to the point that I would consider springing for a 3065X as I can't see needing anything more than that for a very long time. A scope can seemingly do what I want, but does it make sense to use a scope for a multimeter? Plus then I also have to convert for the current clamp (trivial, but a process that needs done none the less).I may still pickup the Rigol scope to play with. I've always wanted one, I just don't think I've ever had a legitimate use for one. Maybe I'm missing out on a whole world of fun, who knows. Maybe I'll pick up one of those inexpensive USB scopes to play with. I'm sure they're pretty much junk and I really hate software controls, but maybe it will be enough to get me hooked.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 05:15:26 am
content: Quote from: billfernandez on July 05, 2017, 04:49:38 amI've actually looked at the Mooshmeter in depth. There are a lot of things that I don't like about it. The software is lacking and since it's ONLY interface is via the software, that's pretty crappy. I really don't want a software only box and really, I don't want a "handheld" box to begin with. I want something that lives on my bench and doesn't move. If I were to end up going the handheld-on-the-bench route, I would just use all Keysight / Agilent meters via Bluetooth into their wonderful Android app.But I do appreciate the suggestion. I think it will ultimately be a nice little box, but it's definitely at a very hobbyist level. Great for guys doing RC and quadcopters and what not I'm sure, but definitely not for me.

author: alm
author_rank: Super Contributor
timestamp: July 05, 2017, 05:48:34 am
content: You do not mind the clicking and wear of the relays on the Siglent scanner card?

author: tautech
author_rank: Super Contributor
timestamp: July 05, 2017, 07:53:39 am
content: Quote from: Brandon_K on July 05, 2017, 05:11:12 amMy inquiries say it's not retrofittable as there's some HW to be fitted on the mainboard.USA made this post:Quote from: Siglent America on June 21, 2017, 01:59:03 pmAnd yet the scanner card IS listed as an option for SDM3045X.Quote from: alm on July 05, 2017, 05:48:34 amHere are the specs:Max AC Voltage125V rms or 175V peak, 100kHz,0.3 A switched, 125VA (resistive load)Maximum DC Voltage 110V, 1A switched, 30VDC (resistive load)Contact Life? 100000 operations?at 1A 30VDC(at 0.5 Hz)? 100000 operations?at 0.3A 125VDC (at 0.5 Hz)Contact Resistance 75 m? ?maximum at 6VDC, 1A?Actuation Time 5ms maximum on/offMaximum swi t c h i n gvoltage250 VAC, 220 VDCMaximum switching power 62.5VA / 30WInsulation Resistance Minimum 1G ohm ?500VDC?Connector Type Clamp terminal, #24 AWG wire sizeNotice the relays are not of the rating of the standard inbuilt Dual measurement relays and as the card is removable it will be quite possible to replace them as needed.There's even a contact resistance spec so you can keep an eye on them.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 09:07:24 am
content: Quote from: alm on July 05, 2017, 05:48:34 amAdmittedly, being unfamiliar with such cards, I was not aware that it would cycle through them as well. I do wonder if it's able to take simultaneous readings from the scanner card AND the main meter inputs, without cycling between the two. Hopefully Scott can cover that in the review. If he hasn't yet shot the review with the scanner card, I may try to contact him and see if he can use my situation (2 current, 2 voltage) as an example test, since it seems like a very real world test. I may be able to supply him with some cells and a PCM to do pre and post PCM readings.

author: Pinkus
author_rank: Frequent Contributor
timestamp: July 05, 2017, 09:13:03 am
content: Regarding to the manual of the scanner card, there is an additional contact PCB needed. Maybe this is not included and it needs to be installed inside the housing somewhere, so you then can just slide the scanner card in and out.See attached screenshot of the manual.If I look to teardown photos, this contact PCB is not installed by default inside the SDM, thus it looks like some connectors need to be added to the main board for connecting the adapter board for the scanner card.Beside of this, the scanner card looks like it could be a nice DIY project to build one on your own .... if we would know the 2 chips on the board (probably just two decoder/driver chips for the relays) and the schematics of the connection board.Maybe later somebody can make high res photos (or scans) of the PCBs and show where these cable connectors has to go to.

author: Brandon_K
author_rank: Contributor
timestamp: July 05, 2017, 09:17:32 am
content: Quote from: tautech on July 05, 2017, 07:53:39 amThat's good to know, but at the same time disappointing. For whatever reason, I just assumed the scanner card would be able to do simultaneous. Of course, by definition, a *scanner* card ... I'm dense!The relay life is not very good. 1 second readings are out, they would last about a day and a half. Even at 1 minute per sample, that's just shy of 70 days. That may be a lifetime for some guys, probably less than 2 years for me.I'm still interested in it. I'll have to make some calls and see how much cheaper I can get it than list.

author: Vtile
author_rank: Super Contributor
timestamp: July 05, 2017, 09:46:02 am
content: https://www.picotech.com/products/data-logger

author: Pinkus
author_rank: Frequent Contributor
timestamp: July 05, 2017, 06:22:51 pm
content: Quote from: tautech on July 05, 2017, 07:53:39 amWell, my SDM3045x does have a button with the writing "Scanner" on it, though when I press it, I get the error message "Function invalid" (presumably because there is no scanner card present). Also the manual of the SDM3045x talks about the 'Optional Multiple Scan Card' so I bet it will work there too. However, if Siglents says 'not retrofittable', they will not sell it as a single unit...... as I said above: time for a DIY solution