Siglent Bench DMMs SDM3065X, SDM3055 and SDM3045X

[Pinkus]

I can confirm, that the new firmware from this site:
https://www.siglent.com/download/firmware/?ProId=25
also works on a SDM3045x (then working as a SDM3055x-e with one extra digit) and is offering the same improvements as on the other SDM DMMs.
Though the response time on the continuity performance did not change dramatically. I have not measured it, but my feeling is that there is at most just a few % improvement. Thus just barley noticeable.

[Mortymore]

The Temperature feature in the SDM3055 not only had "custom sensor" added but also a new feature "Rel Temp (Int/Ext)" that enables the user to tweak the value if "Ext" option is set.



This allowed me to quickly match the ambient temperature reading of a Fluke 54II thermometer. But more is yet to be figured out, since unfortunately Siglent hasn't provided (so far) an updated manual.



The SDM3055 also has the Calibration option, and TheDefpom in his video mentions the 10G input Z might not be present in the other SDM models other than the 3065, but at least SDM3055 already had that feature, in the 200mV and 2V range.

[KungFuJosh]

Is there a special reason the 3045X can't dual view with both resistance and capacitance?

[tautech]

Is there a special reason the 3045X can't dual view with both resistance and capacitance?

RTFM for what combos of dual view are available. 

[KungFuJosh]

Is there a special reason the 3045X can't dual view with both resistance and capacitance?

RTFM for what combos of dual view are available. 

How is that a helpful response? I asked WHY it can't do it. The Shannon tweezers can do it. But this GIANT bench meter that costs 4 times as much can't?

[Kleinstein]

The DMM has only 1 terminal for the test current. So a combined resistance and capacitance would be for a single part / DUT.  The DMMs have a more primitive capacitance function, that may not be really suitable to look at mixed parts that are neither pure capacitors not pure resistors, but something in between.

It would neverthe less be suitable if the meter could measure capacitance with ESR or leakage capacitance. It could be tricky and limited in the range how this can work with the existing hardware. Chances are it could at least for some parts / ranges.

The tweezers are made with the main function to test parts, more like a LCR meter and often they can do mixed part, though still not clear how well.

[KungFuJosh]

The DMM has only 1 terminal for the test current. So a combined resistance and capacitance would be for a single part / DUT.  The DMMs have a more primitive capacitance function, that may not be really suitable to look at mixed parts that are neither pure capacitors not pure resistors, but something in between.

It would neverthe less be suitable if the meter could measure capacitance with ESR or leakage capacitance. It could be tricky and limited in the range how this can work with the existing hardware. Chances are it could at least for some parts / ranges.

The tweezers are made with the main function to test parts, more like a LCR meter and often they can do mixed part, though still not clear how well.

That's interesting. It's funny how little innovation there is with these devices. Make the screen look pretty, but let's keep the actual functionality 30 years old.

I haven't tried the tweezers dual cap/res function on a lot of things, but it works perfectly on their little test board. The Siglent just gets confused on that spot.

My 12 year old Amprobe 37XR-A can read inductance even though it's not an LCR meter, but try finding that on another DMM. The tweezers can do that too of course. You'd think the size of the tweezers would be a limiting factor, but the industry seems to think the bigger a device gets, the less it should be able to do.

[Kleinstein]

The SDM3055 and SMD3065 are more about accuracy with the standard functions of a DMM and not so much about getting many functions. The SDM3045 is more like a SW crippeld cheap version of the 3055 to also cover the 4.5 digit range a complete new design.

Already the capacitance range with quite some DMMs is more of a hack, using the HW made for the ohm function to also measure capacitance with a limited accuracy. One weak point here is that the frequency is not fixed, but usually changing with the range and capacitor. So a nice 2nd display for the capacitance could be the frequencey actually used for the test.
The mixed R and C is capability is really something for a LCR meter. Normal DMMs usually don't provide that function as it would need a different front end to the normal design. A reasonable LCR function (especially the smaller capacitance) can be tricky to combine with good protection against high input voltage.  The LCR meters usually don't have a CAT 2 rating and may already blow from a capacitor charges to only a few 10s of volts.

[tautech]

Is there a special reason the 3045X can't dual view with both resistance and capacitance?

RTFM for what combos of dual view are available. 

How is that a helpful response? I asked WHY it can't do it. The Shannon tweezers can do it. But this GIANT bench meter that costs 4 times as much can't?

Few if any general purpose bench meters offer LCR measurements, LCR meters are specialised instruments.

You don't need lecture me on the value of smart tweezers as I've owned a pair way way before they become well known and purchased particularly for their LCR capabilities and usefulness for SMD.

Even today with nearing 2 decades of use I would replace them in an instant probably with Shannon tweezers rather than any other current instrument for my LCR needs which summed up are DER5000 no thanks, dedicated bench LCR meter, again no thanks.

Once you've used a good set of smart tweezers for a good while and their accuracy meets your needs there is no going back as they are so fast and convenient.
As sick as I am for datasheets, they are the one and only spec for an instrument's capability and the only guide apart from a user manual of what an instrument can do.

SDM models make no claim to provide LCR measurements and never have, sorry if that was an expectation for you and all I can recommend is you get to know the Shannon tweezers and grow to love these special little instruments like I do.

[mawyatt]

We consider the capacitance capability in a DMM as an aid rather than an absolute measurement capability, good for "seeing" if a cap is any good, but not characterizing such, altho one can achieve some reasonable results in certain cases.

Same for tweezers, and they cover the inductance as well, but measuring a component in-circuit and expecting an accurate representation is generally wishful thinking. These are great for trouble shooting, and agree they should be in everyones toolkit, or at least the tweezer cable sets that work with the quality LCR meters, altho they aren't as convenient as the standalone tweezers.

One must realize that the DMM measures DUT capacitance by measuring the charge/discharge cycle characteristics with a rectangular excitation and computes the capacitance based upon this, while the quality LCR meter excites the DUT with a sine wave (at various frequencies) and measures the DUT Voltage and Current with high resolution. These measurement V and I results are Vectors (Magnitude & Angle) and utilized to compute the various DUT parameters which include a host of useful parameters and not just capacitance, nor resistance, nor inductance, but various combinations of such.

For general accurate representations of components these must be measured in a standalone controlled electrical environment and/or fixture, and properly calibrated with the environment/fixture effects removed. For the DMM capacitance capability this requires a single Cal by "nulling" out the residual cable capacitance, whereas the LCR Meters and Tweezers require a 2 Cal procedure, Open and Short, some at various frequencies. Also, some quality LCR meters have an additional Ref Cal procedure with a known Precision Reference Device(s), all at various frequencies, and obviously intended for precision work!

The DMM and LCR meters are completely different instruments, which employ completely different techniques and intended for completely different use cases, and Tweezers may help fill the gap between.

Anyway, having a quality DMM, LCR Meter and Tweezers usually covers all bases, as always YMMV!!

Best,

[KungFuJosh]

That's great info, thank you. Here's my question: how is the Amprobe 37XR-A doing all of it? (No, it doesn't do any dual display stuff) Did they combine separate LCR and DMM electronics in there? The + probe does have to change to a different terminal for L,C, and A compared to R,Diode,V.

[BillyO]

That's great info, thank you. Here's my question: how is the Amprobe 37XR-A doing all of it? (No, it doesn't do any dual display stuff) Did they combine separate LCR and DMM electronics in there? The + probe does have to change to a different terminal for L,C, and A compared to R,Diode,V.

Did you not check out the user manual or spec sheet before buying the meter?  Perhaps you'd be happier sending it back and getting the Amprobe.

It should be obvious to even a complete newbie that putting more functionality into any device adds to the price, especially if you want that functionality to have a high degree of precision and accuracy.  It's a trade off.  I think Siglent were aiming to build a competent DMM and not a swiss army knife.  Jack of all trades and master of none.  Measure inductance to 40H!!!    Who TLF needs that?  Where do you even find a 40H inductor?  On a fusion reactor?

[KungFuJosh]

That's great info, thank you. Here's my question: how is the Amprobe 37XR-A doing all of it? (No, it doesn't do any dual display stuff) Did they combine separate LCR and DMM electronics in there? The + probe does have to change to a different terminal for L,C, and A compared to R,Diode,V.

Did you not check out the user manual or spec sheet before buying the meter?  Perhaps you'd be happier sending it back and getting the Amprobe.

It should be obvious to even a complete newbie that putting more functionality into any device adds to the price, especially if you want that functionality to have a high degree of precision and accuracy.  It's a trade off.  I think Siglent were aiming to build a competent DMM and not a swiss army knife.  Jack of all trades and master of none.  Measure inductance to 40H!!!    Who TLF needs that?  Where do you even find a 40H inductor?  On a fusion reactor?

I've had the Amprobe for over 12 years, it works great. Most inductors I've used it for were between 400 to 700uH.

Guess what? I would pay more for a meter that has those extra functions. But guess what else? You can spend $400 or $40000 and still not get those functions. I would guess the primary reason not to offer them together in a $500 meter, is because you can offer them separately in 2 $500 meters.

[BillyO]

I find it hilarious that you prefer to attack me rather than add to the conversation.

Did I attack you?  How, by asking if you checked out the specs?  You seem surprised by the lack of some functionality.

I thought I was attacking the Amprobe.

[2N3055]

That's great info, thank you. Here's my question: how is the Amprobe 37XR-A doing all of it? (No, it doesn't do any dual display stuff) Did they combine separate LCR and DMM electronics in there? The + probe does have to change to a different terminal for L,C, and A compared to R,Diode,V.

We don't know how it does it and how well it does it. You are the one that have it.
I would suggest to connect oscilloscope in parallel with inductor during measurement and try to measure several different inductors (with  large spread of inductance). Waveform might be a clue how they do it.

As many said already, handheld multimeters very rarely do LC measurements because circuitry needed is not shared with other measurements. Meters that measure C (capacitance) do it by reusing constant current source that is used for resistance measurements and then you only need a comparator and time measurement (already available too) to calculate capacity from charge time... So ading C measurement is trivial LC is not.  Especially with good accuracy and wide range...

All of that is also followed by never cheaper decent LCR meters.... I have UNI-T UT612  that works very good. I paid less than 200 USD for it new and it is really accurate.

If you are not working with high energy, you can get very decent multimeters for less than 50 USD and buy one of good cheap LCR meters, both for less than 200 USD...

That is one thing.
Other thing is that sometimes it is much faster if you have several tools instead of one that you need to switch back and forth all the time... Like having two cordless drills one with a drill and other with a screwdriver bit. Grab one handle and drill, change to other screw in.. It is just faster that remounting drill and screwdriver bit back and forth all the time.....

[KungFuJosh]

Meters that measure C (capacitance) do it by reusing constant current source that is used for resistance measurements and then you only need a comparator and time measurement (already available too) to calculate capacity from charge time... So ading C measurement is trivial LC is not.  Especially with good accuracy and wide range...

What's the limiting factor that makes it so the 3045X can't display R and C at the same time? Is it because the meter is already reading V and I to calculate C?

[Kleinstein]

For not showing C and R (ESR) the limit is likely with the software. In addition the hardware may not easy allow for a good accuracy or some more tricky limitations on the range (e.g. may not work with small capacitors). The ADC in the 3055 and 3045 is not super fast, so it may not work to implement an ESR measurement that is worth having it and not causing more complications / confusions than it actually helps.  I don't have very much hope to see this function as an upgrade from Sigilent. It is nothing you find in a normal meter. Even cheap LCR meters may not show more than just capacitance or inductance or resistance but not support intermediate parts.

[KungFuJosh]

For not showing C and R (ESR) the limit is likely with the software. In addition the hardware may not easy allow for a good accuracy or some more tricky limitations on the range (e.g. may not work with small capacitors). The ADC in the 3055 and 3045 is not super fast, so it may not work to implement an ESR measurement that is worth having it and not causing more complications / confusions than it actually helps.  I don't have very much hope to see this function as an upgrade from Sigilent. It is nothing you find in a normal meter. Even cheap LCR meters may not show more than just capacitance or inductance or resistance but not support intermediate parts.

The test board that I got with the Shannon tweezers had a resistor and a capacitor in series (think it was 10nF + 10K). The tweezers show both values, but I guess that's similar to ESR since it measures Rs either way. This whole thought process started because of that, and the 3045X being able to read C, and totally unable to read R in that case. I guess that's where the LCR wins.

[tautech]

Interestingly although I knew my ST3 tweezers had ESR capability when I brought it, ESR measurements way back then were not as popular as they are today and certainly not the main reason I purchased however it's one of the measurements I now use most. 

But ESR is the dual measurement when in Auto mode something I highly recommended Shannon also implement when he was prototyping the ST42.

[KungFuJosh]

Interestingly although I knew my ST3 tweezers had ESR capability when I brought it, ESR measurements way back then were not as popular as they are today and certainly not the main reason I purchased however it's one of the measurements I now use most. 

But ESR is the dual measurement when in Auto mode something I highly recommended Shannon also implement when he was prototyping the ST42.

Well, they did, so thanks for that. 😉

[KungFuJosh]

I'm happy with the 3045X in general so far, but I'm disappointed that Siglent is shipping units with expired calibration certificates. This seems to be a common thing on Amazon. My cert says 2019. It's not Amazon's fault, the shipping label from Siglent says April 2023 on it. Siglent is shipping them out this way.

[tautech]

I'm happy with the 3045X in general so far, but I'm disappointed that Siglent is shipping units with expired calibration certificates. This seems to be a common thing on Amazon. My cert says 2019. It's not Amazon's fault, the shipping label from Siglent says April 2023 on it. Siglent is shipping them out this way.

Were they discounted ?
Was it supplied with the latest firmware installed ?
Oh that's right, it's now a SDM3055X-E, correct ?

[Martin72]

but I'm disappointed that Siglent is shipping units with expired calibration certificates.

If these certificates are as detailed as the ones Siglent includes with the oscilloscopes, it doesn't really matter....

[KungFuJosh]

Were they discounted ?
Was it supplied with the latest firmware installed ?
Oh that's right, it's now a SDM3055X-E, correct ?

Full price. Doesn't matter what I do with the firmware, they should have at least 2 months of cal time left when they sell them. 2 out of 12 ain't bad, right? But 4 years old for full price? Come on. Mind you, the cert doesn't do anything for me, but that's a value added thing being fully negated by years.

but I'm disappointed that Siglent is shipping units with expired calibration certificates.

If these certificates are as detailed as the ones Siglent includes with the oscilloscopes, it doesn't really matter....

It only matters because it's included in the price of the item. They're sold as having valid calibration certificates, which they don't, because they're expired.

[rf-loop]

Important!:

For SDM3045X only: After now, until further notice,  only valid data sheet is rev.:  EN_04A


https://www.siglenteu.com/download/2587/?tmstv=1684220107