Why did you buy a bench multimeter?  - Page 1
Forum section: electronics / testgear

author: conducteur
author_rank: Regular Contributor
timestamp: July 25, 2018, 07:54:23 pm
content: It may be a silly question, but here we go. (silly questions don't exist, only silly answers!).I'm now a few years into electronics, as a hobby and nowadays also for my studies to become an industrial engineer, and there's one thing that i don't get. It's why many labs have a high end bench multimeter.They're bulky and expensive pieces of test equipment. I know they may have a higher accuracy, but i don't see how I can make use of this. If I measure the 5V rail in my project, I really don't care if it's 5.0001 of 5.0002V?I have now only one desk to do al my work (hobby, university, ...), but now I'm going to build a workbench for everything electronics related with my multimeter, scope, psu, ... so I can leave projects and test setups on the bench while i'm working for school or other things that i have to do.So why does your lab have a digital bench multimeter? Why should I have one instead of a new high end multimeter?

author: Fsck
author_rank: Super Contributor
timestamp: July 25, 2018, 07:55:52 pm
content: So I can datalog endlessly or automate some processes. I have both bench meters and handheld ones.

author: hexreader
author_rank: Frequent Contributor
timestamp: July 25, 2018, 08:01:58 pm
content: So it can be left on all day long without worrying about batteries.It can sit stacked on a shelf out of the way, rather than wasting bench space.High accuracy is rarely needed, but if you are going to bother buying one, why not buy one that will exceed all likely needs now and into the future.

author: hendorog
author_rank: Super Contributor
timestamp: July 25, 2018, 08:10:15 pm
content: Because I can always find it and it doesn't tip over when I pull on the cablesEdit: And because I can stack them on top of each other. They breed you know...

author: kirill_ka
author_rank: Frequent Contributor
timestamp: July 25, 2018, 08:17:51 pm
content: Quote from: conducteur on July 25, 2018, 07:54:23 pmI was thinking the same until I got mine. For me it's more convenient. Because it's always on it's place. Probably you can glue a handheld multimeter to the table to get the same effectAlso buttons are a bit quicker than rotary switch.

author: georges80
author_rank: Frequent Contributor
timestamp: July 25, 2018, 08:19:52 pm
content: Mine (fluke 8845a) was a free score.Sample rate is MUCH higher than a typical portable meter - so can be useful for probing/measuring quickly.With 4 wire it can measure sense resistors (milli-ohm stuff) easily.Backlit, easy to read.I still typically just use my 87III for day to day common stuff - battery life is plenty good.cheers,george.

author: rsjsouza
author_rank: Super Contributor
timestamp: July 25, 2018, 08:20:10 pm
content: As others have said, a meter that stays on a fixed location will have certain convenience benefits that go beyond its specification sheet. I personally have them to save on bench space, being able to leave them turned on for extended periods of time and the possibility of doing data logging. (edit) and also to do 4 wire measurements.Being portable, handheld meters will compromise in certain aspects, mostly to save battery life and reduce size, but will be stronger in others such as robustness against transients and usually aggregate other handy functions such as capacitance meter, continuity beep or temperature, for example (although some more modern bench models are starting to aggregate those as well). My handhelds are used in the field and around the house, where a bench is absolutely useless.

author: nctnico
author_rank: Super Contributor
timestamp: July 25, 2018, 08:24:43 pm
content: I'm baffled by why a bench meter suddenly equals more accuracy. There are also very basic 3.5 digit bench meters.The sole purposes of a bench meter are:1) Mains powered so it never runs out of batteries2) Can be stacked on top or under other equipment

author: DaJMasta
author_rank: Super Contributor
timestamp: July 25, 2018, 08:27:56 pm
content: I've got a 34461A. Data logging and graphing was big for me, seeing trend charts and monitoring drift over long periods can be handy. 4 wire measurement is good too, most handhelds don't have the option, which enables very small meaningful resistance measurements. The raw sensitivity is good too, when you can see thermal drift happening just measuring a regular resistor on your bench with your light on vs. off, and measuring very low level signals - you may not care if your 5V rail is 100uV off, but if your sensitive photodetector increases its output by 100uV you sure want to be able to see it in some situations. Having a very sensitive meter helps a lot when designing very sensitive analog circuits.And I do the vast majority of my work at my bench, so the portability isn't much of a concern.

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 25, 2018, 08:38:24 pm
content: Quote from: conducteur on July 25, 2018, 07:54:23 pmI wanted to do long term or high speed logging in situations where the oscilloscope wasn't the appropriate tool. A bench meter fits the bill very nicely.Most of the stuff I own can be controlled by computer anyway, so neat automated testing can be done.

author: rrinker
author_rank: Super Contributor
timestamp: July 25, 2018, 08:44:34 pm
content: First one, I didn't buy. I got it from the dumpster - it doesn't JUST happen to Dave. Well, it never made it to the dumpster, I was the one tasked with delivering it to the dumpster but I saw a use for it. Venerable Fluke 8012A. It took a while, but that one did eventually give me GAS. Next benchtop I bought was a Fluke 45 on eBay, cheap enough, fully working. Of course it didn't stop there, and in addition to other equipment I also picked up one of those GW Instek ones from the ITT Tech liquidation sale. Mainly because I wanted a relatively new instrument to go along with my golden oldies.The large, bright displays (except for the 8012A) make it easier to read on the bench, and I can continue reading as long as I need to without worrying about batteries. And until my 121GW came the other week, none of my handhelds had all the features of the GW or Fluke 45.

author: andyturk
author_rank: Frequent Contributor
timestamp: July 25, 2018, 08:58:54 pm
content: Who buys just "abench multimeter"? Accuracy increases with the cube of the number of meters on the bench, so you really need more than one.

author: MadTux
author_rank: Frequent Contributor
timestamp: July 25, 2018, 10:40:30 pm
content: Sample rate and really fast beeper/diode test to 7V, good display, much better accuracy, no dead batteries, nice buttons instead of stupid turn switch, doesn't get lost, usually much more repairable, nice aluminum case instead of garbage plastic case, usually better input protection.....

author: Old Printer
author_rank: Frequent Contributor
timestamp: July 25, 2018, 11:03:58 pm
content: I picked up one recently because I was tired of the clutter of a handheld on my small bench top. It sits on top of a bin of parts drawers, up 12" and out of the way. It's always on, no batteries and the leads are just long enough to use but not be in the way. It was cheap, $20 shipped on eBay. It's a BK Precision 2831A, push button, manual range, with reasonable accuracy. Best feature is a large, bright red LED display my 66 year old eyes can read from any angle. So far I am happy, but will probably get tired of the manual range thing.

author: BillB
author_rank: Unknown
timestamp: July 25, 2018, 11:13:17 pm
content: Stationary, always powered, features such as remote control/network connectivity. Linux based and hackable.Eventually, you'll have the desire to figure out how many can you stack.

author: markce
author_rank: Regular Contributor
timestamp: July 25, 2018, 11:37:07 pm
content: Got a used one for less than any decent handheld DMM.- 4-wire ohms measurement- accuracy (got 5 1/2 digit for lees than Eur 100)- Pt100 temp measurement- Cheap quality high voltage probe- GPIB interface

author: RandallMcRee
author_rank: Frequent Contributor
timestamp: July 26, 2018, 12:04:43 am
content: All of the above--plus there are a few "killer" apps that only high-accuracy multimeters can tackle:measure drift over time of your favorite voltage referencematch two or more resistors exactly...measure the temperature coefficient of components...etc.Those are mine.

author: Nusa
author_rank: Super Contributor
timestamp: July 26, 2018, 12:24:02 am
content: The older ones date back to when many people still had analog multimeters, so they were the first digital meters for some.Typically:They have much larger and easier to read displays than handheld meters, regardless of era.They are higher precision than handheld meters of the same era.They have useful features not found on handheld meters of the same era.They cost more than handheld meters of the same era.

author: Muttley Snickers
author_rank: Unknown
timestamp: July 26, 2018, 12:27:18 am
content: I got a bench meter along with some other test equipment to fill up the empty space on a shelf above my desk, this also gives those who enter my work area the misconstrued perception that I know something about technical stuff, I reckon looking the part is just as important.

author: David Hess
author_rank: Super Contributor
timestamp: July 26, 2018, 12:28:51 am
content: Some applications require the higher resolution and accuracy available with a bench multimeter.

author: G0HZU
author_rank: Super Contributor
timestamp: July 26, 2018, 12:40:29 am
content: I've bought a few bench meters over the years but I much prefer handheld meters for everyday casual stuff.I bought my first one (Fluke 45) with a low speculative bid on ebay because it was badly described by the seller and I think I put in the only bid for it (£30) and won!The best advantages of a bench meter have already been listed by others on here but I'll add that this Fluke 45 meter has a really nice relative/dB function that none of my handheld meters have. The display is nice and easy on the eye and the user interface is better than most handheld meters. But it can be a bit slow for certain measurements especially when autoranging.I then bought a Keithley 2015THD bench meter for the onboard AF DSP/generator and SINAD features. It also has much faster datalogging than the very slow Fluke 45. A few months ago I bought another Keithley 2000 bench meter at a local company liquidation auction for a very low price so I could swap the handle/feet kit across to the Keithley 2015THD. It cost me only a bit more than the cost of a 'new' handle/feet kit after I chanced another low bid and won!Here's a few negatives about bench meters.Once on a shelf or a bench the test leads become harder to manage compared to a handheld meter. If you look at many benches here on eevblog the owners usually remove and hide the test leads because otherwise they hang down and often get in the way. Some people have so many bench meters on their shelves it would look like a vintage telephone exchange if you plugged in a set of leads to all of them!The Keithley meters have poor human factors with a really bad display with tiny and poor quality fonts and an awful user interface. They are really meant to be used on an ATE rack I think and the display and user interface become less important. The 2015THD is very heavy and both of the Keithley meters are physically long and might not suit a small shelf. Because the human factors are so poor I rarely use the Keithley bench meters and they spend pretty much all their time in storage in another part of the house. However, I do keep the Fluke 45 bench meter on my work bench all the time these days.Bench meters generally are inferior if you want to do floating measurements on an ultra high Z circuit as they will have some common leakage to ground. A handheld meter shouldn't have this problem.You have to turn on your bench to use most bench meters and they use up a mains power outlet. They aren't as nice to use for closeup work as a handheld meter especially if faultfinding around something in a big chassis on the workbench. The handheld meter is king here because it is so portable and 'plonkable' so you can keep it such that you can see the display without having to shift your vision elsewhere and change focus etc.

author: G0HZU
author_rank: Super Contributor
timestamp: July 26, 2018, 01:03:06 am
content: QuoteAt work across nearly 30 years, I've only seen a bench meter being used a handful of times in our design labs. We have £millions of exotic test gear in these labs and it's mainly RF/comms/DSP based gear. We have plenty of Fluke handheld meters and these are very popular. It's usually only in the ATE/production areas that I see a bench DMM being used.For our various datalogging requirements in the design labs we generally use multi channel ADC based systems as these are faster and more configurable than a bench DMM for the stuff we do. The fact that a bench DMM isn't portable and uses up a precious mains outlet and precious space on an engineer's shelf is also a reason why these meters aren't popular in the design labs. By contrast, a few handheld Fluke DMMs can often be shared around the lab and moved out of the way when not needed.

author: David Hess
author_rank: Super Contributor
timestamp: July 26, 2018, 01:24:19 am
content: Test leads for bench meters? What? Just wire them into the circuit as shown below. If they have real terminal posts, mount the circuit to them and give the safety agencies the bird.I have whole sets of home made test leads which have various clips on the end instead of stabby probes. But if I use them with my handheld meters, the meter tends to get pulled over while the bench meters stay in place.And on that subject, what happened to making handheld meters which did not fall over so easily? A couple weeks ago I saw one with a rounded bottom like some modern PDAs. WTF?

author: Dubbie
author_rank: Unknown
timestamp: July 26, 2018, 01:34:13 am
content: One thing that I have found very useful on my bench meter is the much much greater dynamic range you get with a 6 1/2 digit meter.I also use the trend graph a lot.

author: AtLarge
author_rank: Contributor
timestamp: July 26, 2018, 01:46:47 am
content: As mentioned already I get tired of my handhelds falling over all the time. Made a stand for them and then they are always at the wrong angle for these old eyes. A dedicated spot on the top shelf of my bench and I can always see the readout easily.

author: luiHS
author_rank: Frequent Contributor
timestamp: July 26, 2018, 03:47:04 am
content: Bench multimeters are more comfortable, especially if you have them on a shelf at eye level. I do not look for or need extraordinary precision, only comfort and quality.I have a UNI-T UT804, and I am very satisfied with how it works, and how practical it is.

author: james_s
author_rank: Super Contributor
timestamp: July 26, 2018, 04:07:43 am
content: I bought a bench meter because I wanted one that was always set up on the bench, that I could leave turned on for long periods of time, and that had a serial port for data logging. The nice clear VFD and dual displays were added perks.

author: bitseeker
author_rank: Super Contributor
timestamp: July 26, 2018, 04:19:54 am
content: Since all the serious answers have been given, it's time for a silly one:Because it looks cool!And you can collect them with different types of displays: Nixie, segmented LED, dot LED, VFD, segmented LCD, dot matrix LCD, OLED, etc.

author: dzseki
author_rank: Frequent Contributor
timestamp: July 26, 2018, 08:32:27 am
content: I've had a Metex M3850D (3 3/4 digit) before I changed to a second hand bench multimeter (4 1/2 digit). As you can see the resolution upgrade was subtle in my case, and in fact I could sell the Metex for more money than for what I got the bench multimeter...The resons for the change was the followings for me:-Always lit display (in my case LED) on the bench meter gives good sight in every light conditions.-More convenient to use.-Not taking up board space.-Don't have to care about batteries.-There is no auto power off-Good to have 4wire resistance measurements.

author: TheNewLab
author_rank: Frequent Contributor
timestamp: July 27, 2018, 07:06:24 am
content: I also picked up the GW Instek ones from the ITT Tech liquidation sale. They flooded eBay and was notified by another forum contributor. It is 5.5 digit. I then awoke in the middle of the night with the bright idea of getting a hold of a 6.5 or 7.5 desktop so I could have fun and make a little cash calibrating handheld's maybe even improve 3.5 handhelds and resell.I found an action, had fun bidding it up in the last few minutes..went to bed and awoke the next AMSaying to myself.."now that was really dumb... who would pay anything for a handheld calibration when it would be about the same to buy a new one?" dumb..That said. they were both good deals, they have 4 wire capability, take up a lot of space on my back shelves...and I already have a 4.5 handheld that can be used to log 10,000 inside the unit and unlimited connected to a laptop...For me, as a hobby, I feel it was not so good of an idea getting them, but WTF (that's OK to say, right?)Maybe I can just leave them on, and use the 4 wire resistance without DIYing a constant current source and calculate with 1A and use the voltage reading on the handheld.OH, OH! they make a great night light when you have to go into the room just to grab some tool or something!

author: med6753
author_rank: Super Contributor
timestamp: July 27, 2018, 11:00:33 am
content: Why? Because I can.

author: joeqsmith
author_rank: Super Contributor
timestamp: July 27, 2018, 11:09:14 am
content: Quote from: Nusa on July 26, 2018, 12:24:02 amMy first bench meter was a Fluke 8K. It replaced my second analog meter. It had four D cell nicads as well as the AC. 3.5 digit was all. No interface bus. Cost about a $100 to repair anytime you looked at it funny (back then, not today's dollars). Far outperformed my analog meter and I have used digital meters since.

author: toli
author_rank: Frequent Contributor
timestamp: July 27, 2018, 11:22:18 am
content: A bench meter, while bulky, has its benefits even for hobby yse. For me, its easier to use as its hanging over my bench and I simply need to push a button to change a function. Not need to twist the knob or watch out for it not falling down while I press it or move things around like with a handheld meter. If space is very limited, you can obviously use a handheld meter. Also, the fact you never have to change batteries is great. The battery always dies when you need it most. Other benefits include the the fact it has the ability to use front and read banana-jacks. I always use both, with the front constantly connected to a pair of test leads with thin wires and crown-tip pogo pins, while the back are connected to longer and larger test leads. This comes in handy more than I've imagined. Simply press the button and you can switch between them. The 4 wire resistance measurement is also wonderful if you need to measure low resistances.All of these reasons are obviously the things that are beyond the expected "its more accurate" claim. I've purchased my bench DMM a few years ago (used 34401A) to replace the U1253A I've had at the time as my "accurate" meter, and to accompany the Fluke 189 I have as my main hand-held meter. For most things, you'd be right to assume the accuracy/resolution difference is of no value to me. However, every now and then it is useful. The increased resolution did come in handy when I was working on measuring a few circuits at the time for my M.Sc. thesis. While I did have access to high quality equipment at the university, having the ability to work from home instead of going there was great.I'd also be lying if I said it has nothing to do with always wanting more (and better) gear (toys). Otherwise why would I be looking at ads for another bench meter when I don't really have a need for another one?

author: Gyro
author_rank: Super Contributor
timestamp: July 27, 2018, 12:20:51 pm
content: Why? because they're great fun to repair!

author: capt bullshot
author_rank: Super Contributor
timestamp: July 27, 2018, 12:21:30 pm
content: Guess it's been said many times before, here's my reasons:- No battery- Stackable / and I can put it into the shelf- VFD / LED display vs. LCDMy all time favourite is the HP34401A here, beeing pretty accurate but not volt-nuttery, having the usual functions including a responsive continuity beeper

author: Nusa
author_rank: Super Contributor
timestamp: July 27, 2018, 01:36:48 pm
content: Quote from: Gyro on July 27, 2018, 12:20:51 pmGood point. Assuming it's not a fuse, bench meters are easier to repair than handheld meters.

author: med6753
author_rank: Super Contributor
timestamp: July 27, 2018, 01:41:59 pm
content: Quote from: Nusa on July 27, 2018, 01:36:48 pmAgree on both points.

author: targit
author_rank: Regular Contributor
timestamp: July 27, 2018, 02:27:35 pm
content: 20 amp current range and no battery/timeout power off.

author: Bud
author_rank: Super Contributor
timestamp: July 27, 2018, 03:42:27 pm
content: Quote from: med6753 on July 27, 2018, 01:41:59 pmAnd the older the bench meter is, the easier it is to repair

author: Gyro
author_rank: Super Contributor
timestamp: July 27, 2018, 06:19:01 pm
content: Yes, I agree onallcounts.In my book, things started going to pot when they started putting 'intelligence' in them - even problems like degrading opto-isolators in the Datron 1060 series, which wouldn't have been there otherwise.BTW, I think current ranges are an anathema in bench meters. They're a convenience thing to have on handheld ones but with a bench one it is far better to use a suitable external current shunt and minimize the voltage burden. That's the reason that many traditional bench meters didn't have them.

author: james_s
author_rank: Super Contributor
timestamp: July 27, 2018, 06:27:38 pm
content: Why is an external current shunt preferable? Not saying it isn't, I just have not personally ever wished I had one instead of the built in shunt. Seems like a simple enough feature to include, which does not preclude the use of an external shunt if one prefers.

author: Gyro
author_rank: Super Contributor
timestamp: July 27, 2018, 06:34:45 pm
content: Mostly the voltage burden thing, why have the long leads, non-optimal current shunt resistor (range shared?) when you have decent low-end voltage resolution (1uV in the case of my Datrons). It's the premise that Dave built his uCurrent on - only better. Internal current shunts are ok, but they bring with them fuses and current overload protection hard switching rather than FET etc. 'baggage'.Really just my opinion. [Edit: Sorry I'm drifting the thread off topic]

author: james_s
author_rank: Super Contributor
timestamp: July 27, 2018, 10:50:15 pm
content: Valid points, I can see some advantages to an external current shunt, but I'd still want one built in. I could use an external one if I needed to but it's nice to have the basic functionality there for the many cases where it's good enough. It's not like it adds tremendously to the cost or bulk of the meter to have that as a redundant feature.

author: K5HJ
author_rank: Regular Contributor
timestamp: July 28, 2018, 12:30:25 am
content: Because they're cool.

author: David Hess
author_rank: Super Contributor
timestamp: July 28, 2018, 01:19:38 am
content: Even when I have a multimeter with the proper current range, I may build a current shunt into the circuit for ease of measurement.

author: Cubdriver
author_rank: Unknown
timestamp: July 28, 2018, 06:44:17 am
content: Quote from: bitseeker on July 26, 2018, 04:19:54 amThis. I like old, boat-anchor-y stuff, like nixie bench meters. They stay where you put them, and can remain on all day monitoring things. The main meters I currently use are an HP 3439A, a 3440A and a Data Precision 3500. (That and I have the space for them and no SWMBO to answer to.)-Pat

author: Cubdriver
author_rank: Unknown
timestamp: July 28, 2018, 06:45:23 am
content: And those are some sweet Datrons, Chris! Beautiful!-Pat

author: CJay
author_rank: Super Contributor
timestamp: July 28, 2018, 07:06:17 am
content: I bought mine because mains powered so I don't find I used the last 9V battery in the early hours when the meter tells me I need to replace it, it's still readable when it's out of the way on a shelf so it saves precious bench space, pushbutton control with nice, bright mode indicators, it's (slightly) higher accuracy than my best handheld (but that's not too important for me) and, something I didn't think about until I got the manual, it can be interfaced to a PC for data logging and control which I have a few plans for

author: Muxr
author_rank: Super Contributor
timestamp: July 28, 2018, 07:28:15 am
content: As a non believer for a long time I must admit I have changed my mind on the bench meters. I still use my hand helds for like 99% of all spot measurements, but where bench meters are useful they are irreplaceable.For instance bench meters are perfect for automated measurements, as part of test jigs or as part of long term experiments or characterizations. Hook up a Raspberry Pi to a few bench DMMs, write some Python and the possibilities are endless. A whole world of new type of measurements opens up with added precision as well.Also metrology is a fascinating topic, which I think every electronic hobbyist should check out. You learn some really valuable things trying to build a low drift voltage reference for instance.I was hooked from the moment I read Conrad Hoffman's mini metrology lab series:http://conradhoffman.com/mini_metro_lab.htmlJust beware, it's a rabbit hole that will have you researching exotic resistors, instruments or even just cables and connectors in no time if you're not careful.

author: Fsck
author_rank: Super Contributor
timestamp: July 28, 2018, 07:45:23 am
content: Since we're already off on a tangent. The 8842's VFD is made of sex. Sometimes I feel like I can't bear to wear it out, but I luckily have a spare screen.

author: Gyro
author_rank: Super Contributor
timestamp: July 28, 2018, 12:09:20 pm
content: Quote from: james_s on July 27, 2018, 10:50:15 pmYou're probably (well, possibly) right on the cost. Decent accuracy, continuously rated (as opposed to the 20s rated bent wire hand held DMM ones) shunt resistors aren't that cheap, plus the fusing and extra sockets begins to mount up. No harm in redundant features though.A shameless bump for my shunt collection...https://www.eevblog.com/forum/testgear/my-shunt-collection-(ucurrent-passive)/BTW I see there's currently an ex-MOD Datron 1041M on ebay (not mine).https://www.ebay.co.uk/itm/Datron-1041M-Multi-Function-Voltmeter/183329940794?hash=item2aaf50e53a:g:vjsAAOSwB8lbTcorPersonally, I think it's overpriced at the moment (£110 incl. UK shipping). Looking back, I paid £32.50 incl. for mine but there were a few others being listed at the time. Might be of interest to someone though. Manuals here:http://www.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Datron

author: tkamiya
author_rank: Super Contributor
timestamp: August 01, 2018, 12:34:05 am
content: As I have more and more equipment, I started having a need for a standard. A kind of meter that is calibrated, certified, and more precise/accurate by factor of 2 or so. So, I acquired an HP 6 1/2 bench meter. This is my house standard. Then for casual use, I have much lower resolution and lower quality meters. I do this because if I blow them up, it's not much of a loss, and it's reasonably accurate.Bench meters tend to have larger display, brighter display, and be situated so that it's easier to read. I also have multiple analog and digital hand held meters.Yup, I am an addict.Seriously, even analog meter has a purpose in a way I test stuff. I used to have a bench version of analog meter, too.

author: Jester
author_rank: Frequent Contributor
timestamp: August 01, 2018, 01:17:27 am
content: Same comments as others, portables fall down, constantly need new batteries just when you need to make a measurement, and the display on the portables are inferior.I have 3x 34401a, a Fluke and an Instek and it’s not uncommon to have all five connected to a circuit when testing. Seems like I always need one more, I drag out the 87 or the little pen DMM once in a while and the auto off mode gets really annoying in a hurry.The GOhm input impedance of the 34401a also comes in handy sometimes, perhaps some portables have that now?

author: GregDunn
author_rank: Frequent Contributor
timestamp: August 01, 2018, 05:27:31 am
content: I do have a couple of cheap portable DMMs, but they only get used when I need to measure something far from my bench or an outlet. It's so much trouble to find space on the bench, prop them up, keep from pulling them over when I accidentally tug on a cable, and of course read them from an awkward angle. I may yet pick up another bench DMM just so I can measure (e.g.) two voltages and a current simultaneously - and read them all from one place.

author: mzacharias
author_rank: Frequent Contributor
timestamp: August 01, 2018, 01:44:22 pm
content: I have a really nice Keithley 2015 THD multimeter on the bench, but I mostly ONLY use it for amplifiers under test.For everything else I still just grab of of my (many) Fluke handhelds.So far as being able to leave the bench meter on all the time - I obsess about the FL tube wearing out (aging).I also baby my Fluke 8840A with the cool NASA cal sticker.I have a problem...

author: Specmaster
author_rank: Super Contributor
timestamp: August 01, 2018, 03:09:38 pm
content: I got into bench meters for all the reasons that others have mentioned apart from data logging or automated testing, they are all either 4.5 or 5.5 digit meter and I have plenty of handhelds as well.Bench I have, Solarton 7045, 2 off HP 3466A (with batteries as well) Fluke 8840A, HP 3478A and a Philips PM 2521, Heathkit MM-1U, Heathkit V-7AUHandheld I have 2 off Fluke 27, 7 off Fluke 25, 2 off Bside ADM08A, Proster VC97, Robin OM840(4.5 digit) and Brymen 867 (5.5 digit) plus analogue Avo 8, TMK 500, TMK 700, Kyoritsu 1400, Robin 1503 and an Avo 1001. I think I have a problem looking at this list

author: james_s
author_rank: Super Contributor
timestamp: August 01, 2018, 04:18:21 pm
content: The auto power-off that handhelds all seem to do is extremely annoying, it frequently turns off right in the middle of a measurement I'm taking. It would be nice if they could do some simple checks to determine that the meter is idle, for example if the reading is below a certain threshold likely to be noise. Or make the power off delay something like an hour instead of 15 minutes, it's not like modern meters draw a whole lot of current.

author: Specmaster
author_rank: Super Contributor
timestamp: August 01, 2018, 04:33:14 pm
content: Quote from: james_s on August 01, 2018, 04:18:21 pmSome like the Brymen 867 and 869 you can disable the auto switch off.

author: james_s
author_rank: Super Contributor
timestamp: August 01, 2018, 04:42:42 pm
content: I think it's possible on my Fluke 87 but I don't remember how. Pretty sure it's something you have to do every time you turn the thing on too which is annoying. I would rather forget to turn it off and have the battery go dead than have it turn off in the middle of measuring something. I use rechargeable batteries anyway.

author: PA4TIM
author_rank: Super Contributor
timestamp: August 01, 2018, 04:50:45 pm
content: I have benchmeters for the accuracy, number digits, high speed, no batteries and I just bought one (Keithley 7510) because the specs, functions and enorme wide ranges. Also the filtering/avaraging and statistics are handy. It can measure dry ohm which I a use often and I really like the digitizing function. Together with a Keithley 2000 my most used meters. I have 3x 7,5 digit, 2x 6,5 digit, 1x 5,5 digit and some oldies with nixies. I have two (3 if you count a scopemeter) handhelds I use. (Agilent U1252A and Brymen BM869s) They are handy if I need to measure to far away of the bench and if I need to measure just one thing and do not want to boot up a benchmeter.I need them for my work. You do not need one, if you did you would know

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: August 02, 2018, 05:01:09 am
content: Data logging and computer control, they are easier to read, less flimsy to use, no batteries to worry about. They make for neater bench setups. 4 Wire Ohm is very usefull. My bench meters outperform handhelds, which you don't always need, but can be useful when you do.My K2000 is on 24/7 but also hooked up to the computer, I turn of the display when I'm not using it using said computer.Faster readouts are also nice. I don't know if there are handhelds that support this, but on my Keithley, I can select the 'threshold' of the buzzer in continuity mode. I have had handhelds that considered 50 ohm and even 75 ohm enough to buzz, which is a absolute pain.

author: bitseeker
author_rank: Super Contributor
timestamp: August 02, 2018, 06:31:44 am
content: Good one, blueskull. Kind of like the "Why does everyone have 20 oscilloscopes?" thread.One of my favorite bench DMM shots by HighVoltage (click to enlarge):https://www.eevblog.com/forum/repair/agilent-34410a-repair-attempt-of-2-dead-meters/msg874162/#msg874162

author: Cubdriver
author_rank: Unknown
timestamp: August 02, 2018, 06:39:27 am
content: Quote from: bitseeker on August 02, 2018, 06:31:44 amBah! None of them glow orange!!And as for the twenty scopes, I think I might be over that at this point, but am sort of afraid to actually count the bloody things.-Pat

author: CJay
author_rank: Super Contributor
timestamp: August 02, 2018, 09:36:06 am
content: Quote from: bitseeker on August 02, 2018, 06:31:44 amA person who has one multimeter knows the voltage, a person who has two is never sure

author: Dr. Frank
author_rank: Super Contributor
timestamp: August 02, 2018, 12:42:28 pm
content: Quote from: conducteur on July 25, 2018, 07:54:23 pmThe answer is simple, root cause being nearly 30 years ago, at university..When I started my physics diploma, I made the measurements on superconductors by means of an X-Y chart recorder. I had to convert the voltage of the temperature sensor manually, also the magnetic response signal, and re-draw that by hand in a graph.I had to make many measurements on many samples, in a small time period, and more and more the resolution of that manual transfer was also not good enough.Sensor outputs are often non-linear, and the resolution of the sensor signal may degrade, so that even more resolution of the meter is required. Example: temperature measurement with a PT100 at low temperatures down to 14K.So I started automatic measurements via GPIB bench 5 1/2 DMM, (KEI 193, 194, 199 & scanner, etc.) which at once also solved the resolution / precision problem, which a handheld DMM also would not have covered.Otherwise, with handheld DMMs only, I couldn't have managed at all these many measurement tasks.Later, I even needed a 3458A for fast digitization with high resolution, and for calibration of current sources and temperature sensors.One sentence about the number of nominal digits:Due to the digitization error, the usable resolution is always one digit less than the specified resolution, i.e. a 4 1/2 digit DMM delivers 3 1/2 digits only.. exactly when you need to measure at 1/10 of its range.Therefore, a 6 1/2 digit DMM makes absolute sense, when you need some reserve in resolution, or accuracy.Handheld DMMs are mostly used for qualitative measurements, when you need to know electrical units in the ballpark of a few parts of a % in an electronic circuit.Even 'high end' handheld (do they really exist? ) are not much better in this sense, and have at least a fundamental stability / accuracy problem, e.g. because they can only have a non-heated voltage reference (i.e lacking LM399). So they can't really be 'high end' in this sense.Another disadvantage is the lack of 4W Ohm measurements, e.g. PT100 sensors can not be measured accurately.So in the end, bench DMMs are used for, and are superior over handheld DMMs at:- automation of data acquisition and conversion via professional / reliable / fast interfaces (GPIB, Ethernet)- precise, quantitative measurements- 4W resistance measurements- high resolution, accuracy, stability especially for non-linear signals- simultaneous and synchronous recording of different signal sourcesFrank

author: fanOfeeDIY
author_rank: Unknown
timestamp: August 02, 2018, 01:44:44 pm
content: I bought one second hand just because so many people on this forum had them....I think this is pretty good reason to buy a bench multimeter

author: LaurentR
author_rank: Frequent Contributor
timestamp: August 02, 2018, 03:11:44 pm
content: Quote from: DaJMasta on July 25, 2018, 08:27:56 pmThis. Beyond the obvious (always on, more resolution/accuracy, SCPI), I find myself using the 3446xA trend charts a lot.

author: Wolfgang
author_rank: Super Contributor
timestamp: August 02, 2018, 04:34:11 pm
content: Accuracy & resolution (6 1/2 digits), no battery, low long-term drift, remote control via SCPI, automation.I got a Keysight 34401A and a 34465A.I never saw the features like these in a handheld meter

author: james_s
author_rank: Super Contributor
timestamp: August 02, 2018, 06:30:03 pm
content: Having more than a few of a given instrument I think is a symptom of a broader tendency of hoarding, something which I occasionally struggle with myself. For some reason I've noticed quite a few engineers seem to be hoarders although at least the stuff they tend to hoard is potentially useful and/or valuable. It's not like the mountains of newspapers, pizza boxes or other outright trash that some people hoard.I know a guy whose whole house is packed full of stuff, a lot of it interesting but he has several lifetimes worth of duplicates of many things. He'll buy something on ebay and then a couple weeks later buy another of that same item because it was a better deal. His house is so full of stuff that I doubt he knows what or where most of it is. I was in his garage one time for a half hour working on something before I realized there was a whole car parked underneath a pile of boxes. I don't really understand that, I mean if it's something consumable and one wants to have a spare or two sure, but to buy something just so someone else doesn't get a better deal than you, that's something I'd classify as mental illness.

author: dzseki
author_rank: Frequent Contributor
timestamp: August 03, 2018, 07:23:40 pm
content: Quote from: james_s on August 02, 2018, 06:30:03 pmThere is an other aspect of this as well, that I felt on my skin already. Earlier I had a very limited budget (more or less this stands today still) to spend on home lab equipments, and whenever a "good deal" came up I had to compete with those who have dozens of such equipments already, but obviously have more money to spend on them too. So some (most?) of these instruments end up with these guys sitting idle on a shelf, insted of being used as a "poor guy's" one and only instrument.Furthermore, I think the family members of those who run a home lab rarely have a clue what the home lab really worth, and if shit happens these home labs are tossed for a dime or end up in a landfill because of ignorance or disinterest, Which was completely against the "hoarder's" original intent with those equipments...

author: james_s
author_rank: Super Contributor
timestamp: August 03, 2018, 09:48:41 pm
content: I think that happens pretty frequently. A hoarder dies and their family is so overwhelmed by the mount of stuff and has no idea what's valuable and what's garbage so it all gets hauled off to the dump instead.

author: Specmaster
author_rank: Super Contributor
timestamp: August 03, 2018, 10:49:19 pm
content: I reckon that most families are aware thats there gold in this equipment that people collect together, the only time I can see it being carted off to the dump is where a person who had the equipment lives on their own.

author: james_s
author_rank: Super Contributor
timestamp: August 04, 2018, 12:03:31 am
content: That happens more often than you might expect. The average person can't tell the difference between a piece of equipment that's worth $5,000 and one that's worth $5. To someone like my mom a modern 2GHz oscilloscope is not going to look significantly different than a 30 year old logic analyzer, they're both a box with a screen and a bunch of buttons on it. A lot of times when a relative dies the family is on a tight schedule and just wants to take care of everything as quickly as possible to get it over with. It's a tremendous amount of effort to sort through a deceased person's belongings and figure out what's worth selling and what to just give away or throw away. I've been through the process several times and I'm sure I probably gave away some valuable (non technical) stuff simply because it wasn't of interest to me and there was far too much stuff for me to research every item to figure out what might have value. I'm a lot more averse to throwing stuff away than most people too.I remember reading about a case several years ago where one of those "surplus dealers" ie a guy with a "business" that is really just a front to his hoarding passed away and his family was so fed up with all his "junk" that they had it all hauled off to to the landfill so they could sell the building. He had a lot of good stuff but there was a lot of junk all mixed into stacks of clutter and to them it all looked like garbage.

author: jpb
author_rank: Super Contributor
timestamp: August 04, 2018, 01:46:53 pm
content: Quote from: james_s on August 04, 2018, 12:03:31 amI keep thinking that I aught to list more valuable bits of my electronic kit with approximate values (ballpark) and leave it with my will so my family have a rough idea as to whether or not to sell it on ebay or at least give it to someone who might use it. The drawback with this it they would then know how much money I've wasted to date!

author: james_s
author_rank: Super Contributor
timestamp: August 04, 2018, 05:19:59 pm
content: Quote from: jpb on August 04, 2018, 01:46:53 pmJust because it's worth a particular amount now doesn't mean you paid that much for it. Of course the value can go either direction depending on what it is. I've also had the thought that I should list at least the more valuable or collectible stuff but even so when I eventually expire I'm sure a lot of my treasures will end up in a dumpster. The only other technical people in my family are a generation older than I am.

author: Gyro
author_rank: Super Contributor
timestamp: August 04, 2018, 05:30:37 pm
content: QuoteYes, the other solution is to ensure that at least one of your offspring has followed in your footsteps.

author: james_s
author_rank: Super Contributor
timestamp: August 04, 2018, 05:44:08 pm
content: I have no offspring nor plans to produce any so that won't work for me. For those who do I've observed very limited success in getting one to follow in a parent's footsteps, normally they form their own interests.

author: Gyro
author_rank: Super Contributor
timestamp: August 04, 2018, 06:07:23 pm
content: You're right, ensure was the wrong word, in fact I was quite keen to dissuade him from following in my footsteps (at the time I could see design and manufacture in a lot of the areas I had worked in leaving the country). Luckily he's turned out very flexible, with a decent S/W and H/W balance [Edit: , a healthy CV] and a has a decent, secure, and interesting, niche with a large employer.The other chose Geology fairly early, so the subject never really came up - I'm not sure Sheldon would have been so relaxed about that one though.

author: tkamiya
author_rank: Super Contributor
timestamp: August 05, 2018, 01:10:20 am
content: I didn't know I needed a reason to buy one....

author: james_s
author_rank: Super Contributor
timestamp: August 05, 2018, 04:23:31 am
content: There's always a reason for everything, maybe that reason was a need, maybe you just thought it looked cool, maybe you're a mentally ill hoarder and wanted it to go with the 20 you already had, but there's always a reason.

author: HighVoltage
author_rank: Super Contributor
timestamp: August 05, 2018, 11:18:30 am
content: Quote from: bitseeker on August 02, 2018, 06:31:44 amThat's an old picture.I am afraid to make a new one.One can never have enough Bench Multimeters.Especially when the voltnut metrology virus comes as an infection.

author: Wolfgang
author_rank: Super Contributor
timestamp: August 05, 2018, 12:06:22 pm
content: Your collection is miserably incomplete. An 8 1/2 digit 4ppm Keysight 3485A, or Fluke 8508A is missing.And, where is your Josephson voltage standard ?!

author: james_s
author_rank: Super Contributor
timestamp: August 05, 2018, 03:35:52 pm
content: When was the last time you actually used all of them for something?I have 2 bench meters, one good handheld and a few cheapies, I can't imagine ever needing more unless it was a specialized instrument.

author: iainwhite
author_rank: Unknown
timestamp: August 05, 2018, 04:45:05 pm
content: Quote from: fanOfeeDIY on August 02, 2018, 01:44:44 pmI think that was my reason too.

author: MT
author_rank: Super Contributor
timestamp: August 05, 2018, 08:45:02 pm
content: Because i needed the better specs and remove the battery issue which reminds me i should buy a newer one to geteven better specs the argument back then which also was true at the time but perhaps not anymore. Oh my brain hurts, to much decisions!

author: Nusa
author_rank: Super Contributor
timestamp: August 05, 2018, 09:45:15 pm
content: The biggest problem for some of you is that you don't have enough benches for your bench meters.

author: rsjsouza
author_rank: Super Contributor
timestamp: August 05, 2018, 10:10:42 pm
content: Quote from: Nusa on August 05, 2018, 09:45:15 pmHear! hear!The available space for extra gear has been shrinking by the day...

author: D3f1ant
author_rank: Frequent Contributor
timestamp: August 06, 2018, 02:35:41 am
content: I think the question should be why wouldn't you buy a bench meter?

author: james_s
author_rank: Super Contributor
timestamp: August 06, 2018, 04:02:31 am
content: Lack of a bench, lack of a need, lack of funds, etc. An electrician probably doesn't want to lug a bench meter around to jobsites or try to balance one on top of a ladder. An auto mechanic isn't going to want to find a place to set a bench meter while working on a car. Someone with a low budget would probably be better served by an inexpensive handheld meter.

author: G0HZU
author_rank: Super Contributor
timestamp: August 06, 2018, 09:58:45 pm
content: Quote from: D3f1ant on August 06, 2018, 02:35:41 amI'll list my reasons for not having one where I work... They take up a power socket, they waste space on a shelf, it's also difficult to manage the test leads of a bench meter if it is on a shelf. The leads hang down and will wrestle with other leads on the bench especially during a busy session and it can quickly cause a tangle and a mess. You have to look up and down to read it on a shelf like a nodding dog, you have to reach up to operate the controls and refocus away from the stuff you are working on. You also have to keep moving it (or have another one taking up even more space) if you need to work on stuff along the full length of a bench. They are also no good for floating measurements on a high Z circuit as they have a shunt leakage path to ground (unlike a handheld DMM).I think a bench meter is fine if you only plan to use it lightly in a fixed zone but for any intense work on a PCB or across a large piece of equipment, the handheld DMM is king. As I said before, the biggest difference at work is that the bench meters live in the production/ATE area. A bench meter is a rare sight in the design labs because they are such a PITA to manage on a busy work bench. It's been like this at work for about 30 years and if all the engineers were offered a free megadigit bench DMM to have on their bench permanently I think nearly all of them would say no. This is for the reasons given above.

author: Specmaster
author_rank: Super Contributor
timestamp: August 06, 2018, 10:14:16 pm
content: There is no real definitive answer to this question for hobbyists, many times as for me its a matter personal choice. There are times when you don't actually have any space left on the bench due to the size of item that you are working on. That's when a bench meter mounted on a shelf or rack above the bench is your friend because the meter is there to hand, it is above the bench top height so is clearly visible and not hidden behind the item of interest. Other time you might need to use a meter away from the bench and that when and where decent handhelds come into their own.A well equipped lab will more than likely have a few meters of both types to enable for flexibility and changing conditions etc.I know I have plenty of both types and they all get used.