Looking for a hobbyist bench DMM

[Shimonu]

My electronics hobby is getting more serious and I feel like upgrading from my current budget handheld UNI-T. It doesn't suit me when I'm programming and wanting to monitor voltage for instance as it can sit idle for long periods and then auto power off after a short while leading to me having to constantly turn it on. As I'm mostly measuring by the desk I would prefer something more permanent so I'm looking for a bench DMM.
I haven't had any great use for high accuracy except lately wanting to measure nanoamp currents for low-power projects but with that said I do see this as a long term investment and should cover my needs long term. So I would love some tips.

Rough requirements

• Bench DMM
• At least 5½ digits
• Physical depth should not be above 35 cm so used 34401A and similar are a bit too big from what I've seen
• €500-1000 preferably but could go higher

Other nice to have

• PC/LAN connectivity for remote control
• Trend chart is nice I've heard

I've tried to do research on units like the Siglent SDM3055, SDM4055A or Hantek HDM3055 but I don't see a lot of reviews or teardowns so it feels difficult to get a sense of their quality and performance after long term use. Some say they're great while others say they get DOAs or have found some annoying behaviour.

Any obvious choices for the budget?
Any features I should really look for that I might not know about or have listed?

[bdunham7]

If you really mean "long term investment" I'm not sure the Siglent, Rigol or Hantek products are what you want.  That's based on what has been discussed here and elsewhere, not my personal experience.

I can tell you about the ones I have, I'll refrain from presuming I know exactly what you want or how they compare to other things that I don't have. However, my ultimate suggestion is something I don't have.

I have 3 meters that would work for you.  I'm not considering older models that only have GPIB or have limited features.  I have the HP34401A, Fluke 8846A and Fluke 8808A.  These meters are ~25, 15 and ~12 years old respectively.  The Fluke 8845A is very similar to my 8846A with a bit less accuracy, lower ACV maximum (750 vs 1000) and no capacitance or temperature ranges.  Any of these would be good choices IMO if you can get a decent deal on them.  Only the 8808A is still available new and it is too expensive for what it is IMO.

The 34401A is just under 36cm long with both bumper installed, the case might sneak in under 35cm by itself.  You'll have to consider how critical that dimension is.   Only the 8845A/8846A have LAN, the 8808A and 34401A have RS232 ports that can be easily adapted to USB with a cable.  IDK how rigid your LAN requirement is, but I find RS232/USB works just fine.  Trend chart and other on-screen tools are nice, but I've not been using them at all since I got the Testcontroller program from user HKJ.   For logging and similar meaurements I connect the meters and then turn the displays off and do all the work from the PC.  YMMV.

If you really want to make a long term investment and want maximal accuracy and excellent low current ranges then,  if you can, stretch your budget and get a Keithley DMM6500.  IDK what those cost in your area, perhaps that's just too much. 

[Grandchuck]

How do you feel about used DMMs?  HPAKs and Keithleys and others can be found that are worth looking at.

[ch_scr]

For the budget you should be able to get a good, modern, used 6 1/2 digit meter. The depth is the hard part.
Keithley 2110 (aka Picotest M3510a) is only 30cm deep, but it's pretty expensive for what it is.
Keysight 34460A / 34465A is also only 30cm deep - probably what you should be after (6 1/2 digit, trend plot).
Look in the forum for caveat with the older 34460A before buying a used one.

[Aldo22]

My electronics hobby is getting more serious and I feel like upgrading from my current budget handheld UNI-T. It doesn't suit me when I'm programming and wanting to monitor voltage for instance as it can sit idle for long periods and then auto power off after a short while leading to me having to constantly turn it on.

A bit off-topic, but are you sure you've read the manual?
Even on my super cheap UNI-T UT123 you can turn off auto-shutdown.
Just hold down the "select" button when switching on.

[Zenith]

I've tried to do research on units like the Siglent SDM3055, SDM4055A or Hantek HDM3055 but I don't see a lot of reviews or teardowns so it feels difficult to get a sense of their quality and performance after long term use. Some say they're great while others say they get DOAs or have found some annoying behaviour.

There are a few reviews and teardowns on Youtube.  Enter say, "Siglent SDM3055 Digital Multimeter" in the search.

It's not a thing I've looked at. My bench multimeter is an an ancient Solartron 6.5 digit, which I have no intention of replacing. I'd assume that Siglent, Rigol and others make products that are value for money, but might not have the support, or be intended for the level of service, that Keithley etc are. Buying used instruments can also be venturing into a minefield.

[Shimonu]

If you really mean "long term investment" I'm not sure the Siglent, Rigol or Hantek products are what you want.  That's based on what has been discussed here and elsewhere, not my personal experience.

I can tell you about the ones I have, I'll refrain from presuming I know exactly what you want or how they compare to other things that I don't have. However, my ultimate suggestion is something I don't have.

I have 3 meters that would work for you.  I'm not considering older models that only have GPIB or have limited features.  I have the HP34401A, Fluke 8846A and Fluke 8808A.  These meters are ~25, 15 and ~12 years old respectively.  The Fluke 8845A is very similar to my 8846A with a bit less accuracy, lower ACV maximum (750 vs 1000) and no capacitance or temperature ranges.  Any of these would be good choices IMO if you can get a decent deal on them.  Only the 8808A is still available new and it is too expensive for what it is IMO.

The 34401A is just under 36cm long with both bumper installed, the case might sneak in under 35cm by itself.  You'll have to consider how critical that dimension is.   Only the 8845A/8846A have LAN, the 8808A and 34401A have RS232 ports that can be easily adapted to USB with a cable.  IDK how rigid your LAN requirement is, but I find RS232/USB works just fine.  Trend chart and other on-screen tools are nice, but I've not been using them at all since I got the Testcontroller program from user HKJ.   For logging and similar meaurements I connect the meters and then turn the displays off and do all the work from the PC.  YMMV.

If you really want to make a long term investment and want maximal accuracy and excellent low current ranges then,  if you can, stretch your budget and get a Keithley DMM6500.  IDK what those cost in your area, perhaps that's just too much.

The DMM6500 is certainly a bit above the budget, seems to be around €1700. But I'm thinking I should have this for 10 years and still feel happy with it. I don't want to be looking for something new after 3-4 years. So the price isn't really that much of a show stopper. The trouble with the 6500 is that it seems to be out of stock. Some places have it but it's more expensive then.

I'll see what I can find used but I'm not sure I want to spend a lot on something used unless I'm sure it'll be a safe buy. If it's ~€200 I won't feel too bad if it ends up breaking soon after but I don't want to buy something used for €700 and then have it be broken or fail soon. I'd really prefer spending more and have warranty with a reputable store.

My stomach has been telling me that I should probably be looking at a Keysight 34460A or better for it to be a good investment. It just feels so tempting when you see the chinese versions for a fraction of the price and people seemingly happy with them.

I've sent a question to a store to see when they get the DMM6500 back in stock. It seems nice with the big display.

The 35 cm isn't strict, it's just that the instrument will start to encroach on the work area a bit too much for my taste. 36 cm wouldn't be a problem especially if you can push it right against the wall and still get the mains out.

[bdunham7]

The 35 cm isn't strict, it's just that the instrument will start to encroach on the work area a bit too much for my taste. 36 cm wouldn't be a problem especially if you can push it right against the wall and still get the mains out.

You need another 2cm or so for the serial port and mains connectors, maybe less if you have a right-angle IEC cord.  But I totally forgot that the DMM6500 is really long as well!  So that's not going to work unless you rearrange something.  Perhaps a riser?

[KungFuJosh]

Rough requirements

• Bench DMM
• At least 5½ digits
• Physical depth should not be above 35 cm so used 34401A and similar are a bit too big from what I've seen
• €500-1000 preferably but could go higher

Other nice to have

• PC/LAN connectivity for remote control
• Trend chart is nice I've heard

I've tried to do research on units like the Siglent SDM3055, SDM4055A or Hantek HDM3055 but I don't see a lot of reviews or teardowns so it feels difficult to get a sense of their quality and performance after long term use. Some say they're great while others say they get DOAs or have found some annoying behaviour.

Any obvious choices for the budget?
Any features I should really look for that I might not know about or have listed?

In your budget, you could get a nice 6.5 digit meter. I own the SDM3065X, Keithley DAQ6510 (same analog board as DMM6500), and Keysight 34465A. They're all good, but my preference in order is Keithley, Siglent, Keysight.

The Keysight is nice, but the continuity options are lacking compared to the other models (despite being very fast), and it hasn't had a firmware update in years, despite the fact that it could certainly benefit from one.

IME, the Siglent SDM3065X is the best bang for the buck model. It needs some burn in time for stability, but I have not had any issues.

In your budget, you should be able to afford the newer SDM4065A (which seems to maybe not need the burn in time?). If you're not in a hurry, you can wait a while and the firmware will get developed farther before your purchase it. Or if you want to be an early adopter, you might have to deal with some hiccups before it gets fixed. This is speculation- I have no reason to believe there will be issues other than that there usually is something people find when a new product is released from any brand.

IME, Keithley is the best, both from the perspective of the hardware itself, and their support. You can find a used DMM from them in your budget. The DMM6500/DAQ6510 have the most advanced graphing and data available from any of these meters.

Keithley's support thus far, has been incomparable. Siglent support has generally been good to me, but still comes in second behind Keithley. Keysight support was okay at best so far, but certainly nothing to brag about.

Your depth requirement might not fit the Keithleys, but you can do what I did (if you have the space) and design support for them to hang off the back of the bench, rather than take up extra space on the bench. Both the Siglent and Keysight should fit your space requirements otherwise.

Thanks,
Josh

[Shimonu]

Hmm, maybe I should rethink the dimension requirement
The Keithley seems nice, but I saw even the new Siglent SDM4065A is just under 38 cm and I think I could still live with that. I could probably also reorgnize the desk to make it work.

All great input. I'm in no rush at the moment and that wouldn't fit with this being a long term investment. I'm mostly excited about getting a new multimeter but nothing that is required for any project at the moment.
I saw a used HP34401A on ebay the other day. Maybe I'll see if that's still available and have another think about the size.

[asmi]

Hmm, maybe I should rethink the dimension requirement

This is the part that I don't really understand - why are they so damn long? What's inside of them which requires such ridiculous dimensions?

[KungFuJosh]

Hmm, maybe I should rethink the dimension requirement
The Keithley seems nice, but I saw even the new Siglent SDM4065A is just under 38 cm and I think I could still live with that. I could probably also reorgnize the desk to make it work.

All great input. I'm in no rush at the moment and that wouldn't fit with this being a long term investment. I'm mostly excited about getting a new multimeter but nothing that is required for any project at the moment.
I saw a used HP34401A on ebay the other day. Maybe I'll see if that's still available and have another think about the size.

I wouldn't waste any money on those old HPs. For what people sell them for, you can get a much nicer newer DMM with much more capability. If you want an extra meter that doesn't have all the extras, then start with the 34410A, which at least has ethernet. Still, I wouldn't waste time with that unless you like the old look of mediocre screens. 😉

I think choosing between the DMM6500 or the new SDM4065A is a good way to go. If I get my hands on the new Siglent, I'll be posting some comparison videos between all of these meters I mentioned.

ETA:

The DMM6500 dimensions:
Rack Dimensions (W × H × D) 213.8 mm (8.42 in.) × 88.4 mm (3.48 in.) × 356.6 mm (14.04 in.)
Bench Dimensions (W × H × D) 224.0 mm (8.82 in.) × 107.2 mm (4.22 in) × 387.4 mm (15.25 in.)

You're under 39cm either way, but you do have to account for things sticking out of any of these meters (ethernet, power, scanner card stuff, etc.).

[tautech]

Hmm, maybe I should rethink the dimension requirement

This is the part that I don't really understand - why are they so damn long? What's inside of them which requires such ridiculous dimensions?

Length is required to accomodate a scanner card in models that use them.

[bdunham7]

I wouldn't waste any money on those old HPs. For what people sell them for, you can get a much nicer newer DMM with much more capability.

The prices are a bit rich these days and condition can be an issue, but if you just want a stable, accurate and durable (and repairable if needed) meter the old 34401A is hard to beat.  Granted, the "UI" is a bit tedious, but with a serial-to-USB converter they're quite easy to connect to a PC and do whatever you like.  When one could get a nice one with the later firmware for $200-250 it was a no-brainer.  A beater for $600 is another story.  A whole bunch of new-old-stock-ish ones flew out the door at 400€ on eBay recently.

You might say that a hobbyists needs are different, but depends on your hobby! 

[coromonadalix]

forget the non black 3446x  models,   we have many threads of failed spear mcu's, memory problems etc ...   get a black one,  if not,  forget theses series

[KungFuJosh]

The prices are a bit rich these days and condition can be an issue, but if you just want a stable, accurate and durable (and repairable if needed) meter the old 34401A is hard to beat.  Granted, the "UI" is a bit tedious, but with a serial-to-USB converter they're quite easy to connect to a PC and do whatever you like.  When one could get a nice one with the later firmware for $200-250 it was a no-brainer.  A beater for $600 is another story.  A whole bunch of new-old-stock-ish ones flew out the door at 400€ on eBay recently.

You might say that a hobbyists needs are different, but depends on your hobby! 

He had interest in trend charts, and once he sees stats, graphs, etc. available in newer DMMs, all of those old models are off the table. And like you said, people get cuckoo with what they're asking for them.

forget the non black 3446x  models,   we have many threads of failed spear mcu's, memory problems etc ...   get a black one,  if not,  forget theses series

Agreed, but the Keysights are mostly out of his budget anyway, and not worth it IMO compared to Keithley or Siglent. I get that some people don't like to learn new things like touch interfaces (which I think are awesome), but I can't imagine paying more for a 34465A over getting a DMM6500 for ~hundred(s) less.

The DMM6500 has the added benefit of the very inexpensive DIY scanner card voltsandjolts worked on.

[nctnico]

For everday use, I'd look at the VC8145 4.5 digit DMM. This has been my daily driver on my bench for 10+ years already. I can't find something else which is a suitable replacement (even before considering a budget). I only use my Keysight 34461A when more accuracy is needed (or trend plotting).

[bdunham7]

The DMM6500 has the added benefit of the very inexpensive DIY scanner card voltsandjolts worked on.

More and more I keep running into situations where the scanner function would be handy...

[KungFuJosh]

The DMM6500 has the added benefit of the very inexpensive DIY scanner card voltsandjolts worked on.

More and more I keep running into situations where the scanner function would be handy...

I have the 7700 card in my DAQ, and it's pretty awesome. The simpler card for the DMM6500 would be great if you need the feature. Let the TEAS win!! 😉😉

[artag]

I'd also recommend a 34401A or a Keithley 2000 but if the size problem is a breaker there's the older 5 1/2 digit 3468A with an HP-IL interface - it's only 270mm deep.  An HP-IL to USB interface is available fairly cheaply as the PIL-BOX.

There's also the 3478A with HP-IB but it's in a bench case which is just as large as the 34401A. May be cheaper, though. HP-IB is cheap and easy to use with adapters such as the AR488 arduino-based device.

The display on the 34401A is a VFD and a delight compared to the unlit LCD on the 3468A, but do make sure it's not faded. Replacements are available but that's more cost.

And don't forget, if the hobby's getting serious .. you're gonna need a bigger bench .

[tooki]

Hmm, maybe I should rethink the dimension requirement

This is the part that I don't really understand - why are they so damn long? What's inside of them which requires such ridiculous dimensions?

These sites have extensive photos of the internals of the DMM6500:
https://xdevs.com/review/dmm6500/
https://lygte-info.dk/review/DMMKeithley%20DMM6500%20UK.html

[tooki]

The DMM6500 has the added benefit of the very inexpensive DIY scanner card voltsandjolts worked on.

More and more I keep running into situations where the scanner function would be handy...

Yeah! I’ve been thinking about building one of the clone scanner card projects for the DMM6500 at work.

[Aldo22]

For everday use, I'd look at the VC8145 4.5 digit DMM. This has been my daily driver on my bench for 10+ years already. I can't find something else which is a suitable replacement (even before considering a budget).

Can you explain why, if it's not about the budget?

[ftv]

How about the GW Instek GDM-9061? It meets all requirements including dimensions with a margin:

Dimensions (W x H x D)

267 mm x 107 mm x 302 mm ~ with bumper
220 mm x 88 mm x 277 mm ~ without bumper

[Sorama]

Let’s be honest, all you need is a Siglent 4xxxx.

It ticks all the boxes, is cheap and if it doesn’t suit you anymore in 5 years, then buy something else.
You can have 3 for the price of 1 Keithley.

Why o why do newcomers so badly want old stuff with a unknown history, no support no life expectancy…

It’s like Brigitte Bardot… in those days we would all like to spend a night with her… but do we still ?

(Sorry Brigitte)