Siglent Bench DMMs SDM3065X, SDM3055 and SDM3045X

[delvo]

But it makes measuring the voltage on a supercap bank so much more exciting if you you are one button press away from explosion. 

[techneut]

Booom is Ho ?

[colorado.rob]

Higher accuracy is what interests me, otherwise any problems regarding reliability ?

I have had the SDM3065X for 6 years. It has never given me a problem. I use it primarily for current measurement of very low power devices (100nA to 5uA sleep currents). Even in its 20mA range, the instrument is accurate enough to provide the information I need. The graphing and histogram features are quite useful to me, as is the dual display. My only regret is that I could really use the scanner card now and it's not an upgradeable option.

[KungFuJosh]

Higher accuracy is what interests me, otherwise any problems regarding reliability ?

I have had the SDM3065X for 6 years. It has never given me a problem. I use it primarily for current measurement of very low power devices (100nA to 5uA sleep currents). Even in its 20mA range, the instrument is accurate enough to provide the information I need. The graphing and histogram features are quite useful to me, as is the dual display. My only regret is that I could really use the scanner card now and it's not an upgradeable option.

The scanner card is available separately. It's the SC1016. Does your older model not have the cutout on the back panel for it?

[delvo]

My SDM3065X doesnt have the cutout

[tautech]

Higher accuracy is what interests me, otherwise any problems regarding reliability ?

I have had the SDM3065X for 6 years. It has never given me a problem. I use it primarily for current measurement of very low power devices (100nA to 5uA sleep currents). Even in its 20mA range, the instrument is accurate enough to provide the information I need. The graphing and histogram features are quite useful to me, as is the dual display. My only regret is that I could really use the scanner card now and it's not an upgradeable option.

The scanner card is available separately. It's the SC1016. Does your older model not have the cutout on the back panel for it?

SC cannot be retrofitted.

From the US website:
NOTE: The scanner is included on new SDM3065X-SC products only. It cannot be added to SDM3065X instruments at a later time.

Recent discussion:
https://www.eevblog.com/forum/testgear/multi-channel-multimeter-with-usb-interface/msg4960108/#msg4960108

[KungFuJosh]

SC cannot be retrofitted.

Oh, that's kinda lame. I thought Siglent loved selling addons. 😉

[Martin72]

SC cannot be retrofitted.

Interesting:
The SC models are sold (at least here in Germany) together with the scannercard, the models are not available without it.
The additional price compared to the non-SC models corresponds approximately to the unit price of the scannercard.
But you can not install it in a model without -SC....

[tautech]

And its rediculous into how many menus you have to go to to take a screenshot.

Yes a few instruments from that era of design are a pain to grab USB screenshots with.....
Maybe it's time for a new feature request to much improve that.

I'll give this some thought and forward a suggestion......something like pressing 2 specific buttons together saves screenshot to USB ?

Better ideas ?

Done.
Suggested a long press of Run/Stop for capturing a USB screenshot.

Had a SDM out and that just seemed to make the most sense.

[Mortymore]

The button for printscreen should be one that if short pressed by mistake, doesn't do immediately anything, like the SHIFT button.

Just a thought

[Martin72]

The die is cast, I will treat myself to an SDM3065X.
Let's see if Batronix can still do something on the price, they don't have it in stock, another dealer does, but I hope for some discount with them.

[KungFuJosh]

The die is cast, I will treat myself to an SDM3065X.
Let's see if Batronix can still do something on the price, they don't have it in stock, another dealer does, but I hope for some discount with them.

They owe you for selling 1000 of their MSO demo boards!

[tautech]

The button for printscreen should be one that if short pressed by mistake, doesn't do immediately anything, like the SHIFT button.

Just a thought

Shift already has dual functions, Shift and Remote/Local control so not at all suitable for a Long press for anything.

However the Run/Stop button has only a toggling state and no dual function and if we are to think more deeply about the screenshot shortcut we want, a display snapshot in time mimics the Stop state hence the reasoning behind suggesting use of Run/Stop to Siglent.
Seemed darn obvious after having a play and a think about how to best add a screenshot shortcut to existing functionality.

[skander36]

The die is cast, I will treat myself to an SDM3065X.
Let's see if Batronix can still do something on the price, they don't have it in stock, another dealer does, but I hope for some discount with them.

I would suggest to go to a Keythley DMM6500 instead.
My 3065X even after calibration to Siglent Augsburg does not show the same values as the DMM 6500 and KS43465A does.
Plus the DMM6500 scanner card can be cloned and fitted very easy. (plus local running scripts, apps, custom trigers, advanced UI, etc.)

[Martin72]

Hi,

My 3065X even after calibration to Siglent Augsburg does not show the same values as the DMM 6500 and KS43465A does.

It doesn't have to, as long as it stays within its (own) specification - Does it ?

plus local running scripts, apps, custom trigers, advanced UI, etc.

The Keysight also costs almost twice as much, so it should have more to offer.

[skander36]

Hi,

My 3065X even after calibration to Siglent Augsburg does not show the same values as the DMM 6500 and KS43465A does.

It doesn't have to, as long as it stays within its (own) specification - Does it ?

This is what I am talking about.
Siglent is in left. Calibrated in March this year. KS an KT are out of cal. interval.
Voltage source in this pictures is Ian's PDVS2 mini.

[Martin72]

Hi,

Calibrated in March this year.

What "says" the protocol ? Is the unit in its specs ?

KS an KT are out of cal. interval.

OK...
So you compare a "fresh" calibrated meter with two others out of cal, right ?

Voltage source in this pictures is Ian's PDVS2 mini

When was this one calibrated ?

[skander36]

It seem that I'm loosing my time ...

[Martin72]

Why ?
You have raised an important objection that needs to be explored.
I don't want to spend €800 only to be told a year later during external calibration that my meter is out of tolerance.
That's why I would like to know what's wrong with it before I buy it.
It's not about which measurement result looks "nicer".
If, for example, your newly calibrated Siglent measures something different than the two that are no longer calibrated, it may well be that it is nevertheless closer to the "truth".
I think that would also be important for you to know.
Simply saying that it shows something different is a bit too shallow.

[skander36]

Due dates:
PDVS2 - 1 year July 2023
KS34465A - 1year Nov. 2022
DMM - 2 year March 2023

None of them are known as drifted so much so soon.
KS and KT have shown the same close values form the first day when I get  PDVS2.
The fact that both dmm's show very close results should tell you something.
In any case I will not trust the 3065X more than KS and KT.

[alm]

If, for example, your newly calibrated Siglent measures something different than the two that are no longer calibrated, it may well be that it is nevertheless closer to the "truth".

The way calibration intervals work, is that manufacturers come up with specifications that will, at some confidence level, confirm that the meter stays well within them for the calibration interval. This is generally a number that's padded to some degree to make sure the long tails of the Bell curve are still within spec. No company that cares about calibration would use a meter if only 68% of the meters are still in spec at the end of the calibration interval. Then the calibration interval needs to be shortened. Actually, any meter being out of spec at the end of its calibration interval is a problem, because it means you can't rely on any of the measurements you took since the previous calibration, and would have to recall all products that rely on this measurement. I'm not saying it doesn't happen, but it's generally very rare, especially for the low voltage DCV ranges.

So while it would certainly not convince an auditor, I'd have a fair amount of confidence that the Keysight and Keithley meters will still be in their one year spec after a year. For example from a data set I downloaded from the PMEL forum a long time ago, out of 250 calibrations of a HPAK 34401A at 1 V DC with roughly 1 year interval, zero where out of tolerance. Out of 118 Keithley 2000 calibrations at 1 V DC, one was out of tolerance. Both companies have decades of experience burning in and selecting the LM399 voltage references they use.

From what I've read, for example here, Siglent uses LM399 references without such selection and burn in. So it would be very plausible that the Siglent meter drifted rather than the other three devices all drifting at the same rate and in the same direction. If you buy the meter and leave it on for a couple of months, and then have it calibrated, it may well drift less.

You should properly run the numbers with the uncertainties of all meters to figure out if this is actually out of spec. Because 50 ppm difference might well be borderline in spec. Note that the other devices will likely also be somewhat off in either direction. Consider it four overlapping bell curves with the reading as their mean and 3.33 * their uncertainty as their standard deviation (per GUM).

[Martin72]

Thankyou both, the thing with the LM399 I did not know until now.
Hm-Hm...

[mawyatt]

One reason we selected the KS34465A as our 1st new precision DMM (had an HP & AG 34401A) here at the Labs, was because we hoped/wished/thought or whatever that some of the old 34401A DNA would be in these newer DMMs.

Now we have 3 KS34465As, a pair of 34401As, a DMM6500 and a SDG3065X, and they all agree well altho the SDG3065X is always slightly higher in DCV readings, likely because the LM399 is still "aging".

As for finding the "Truth" measurement, think if 5 or 6 DMMs agree within reason, then the "Truth" is within reach. Of course if one must have verified results then the "Truth" is calibration to traceable standards, which we recently did with a project where the results needed to be verified and repeated elsewhere. New KS34465A (active new cal certificate) solved this issue as measurements compared with a couple other KS34465As and a DMM6500, and other instruments outside our control.

We have a LTZ1000 and a couple LM399 based references, and a few other references (Vref10) that all run 24/7, the LTZ and LM have ~2 years aging. These are used to periodically check various instruments against each other to attempt to spot a deviant instrument before making suspect measurements.

Best,

[slavoy]

And now I just became dissatisfied with my SDM3065X    I bought it new from a local distributor, and it turned out the factory calibration certificate was from 2019... I plan to send it for calibration soon and will let you know how it turns out (unfortunately, I don't have a stable reference source to check the drift.)

[Martin72]

Thank you Gentlemen, now I´m unsure what to do.

For the first sight, the DC values doesn´t look bad against the mentioned keysight, see pic.
But this one costs more, 600 bucks more...
Hmm...Buying the SDM and let it on for weeks...
I hope in the case of the 6.5 digit meter it would come with a proper cal. protocol instead of simply one sheet.