Bench or portable multimeter - Page 1
Forum section: electronics / beginners

author: BBP
author_rank: Newbie
timestamp: July 29, 2010, 04:56:29 am
content: Hi All,Newcomer to this forum, and getting back into electronics after a long hiatus.I don't want to start another multimeter thread, but I did a search and had no luck, so I guess I will have to just ask outright. I apologise if it has been raised before and I was not thorough enough in searching.I have noticed that most seem to regard Fluke or Agilent as their preferred brand of multimeter, and fair enough too. Also a lot of the discussion is about handheld/portable units. I have a basic handheld DMM I have had for many years and it gets kicked around the place and does the general stuff. I now wish to get a new one of much higher capability and accuracy. Yes, I know those two requirements generally mean $$$.I have a preference towards a bench meter as I don't see myself having that need to go into the "field" where I would need high accuracy etc, so my old one would do there. In considering a bench meter, would one apply the same criteria used with handhelds or is there something else one should look at. I can assume there are obvious things with handhelds such as battery life, being able to be taken canyoning, etc, would not really apply to a bench unit. The main reason I am thinking bench is that I hate gear which slides around, tips over when you go to adjust it etc.Now as a hobbyist I cannot quite justify the cost of a Fluke/Agilent bench meter. That is not to say I don't have the capacity to get one of them, more that I tend to be very pragmatic in that if I don't use something regularly enough it is hard to justify the purchase. I was looking a some Thurlby Thandar (TTI). Such as the T1604 or 1705. Their specs seem adequate for my requirements and the price is justifiable. I used to know them as a reputable company and it appears their stuff is still made in the EU. Are they still OK, or am I better off staying with US gear. I like to buy once, but keep things within reason. Means I can buy more toys without crawling to the minister of finance for permission each time.Cheers,Robin

author: EEVblog
author_rank: Unknown
timestamp: July 29, 2010, 05:32:31 am
content: Forget bench meters unless you have a specific requirement for one.Hand held meters are infinitely more versatile.Even if you have a small bench, it's handy to be able to place your meter anywhere you want and not worry about a power cord.Dave.

author: david77
author_rank: Frequent Contributor
timestamp: July 29, 2010, 06:51:52 am
content: A good hand held meter is worth it's weight in gold, true.But I wouldn't want to miss my bench meter for two main reasons: It is always where I do 99% ofelectronics work: on my bench in my workshop. And second as long as I've got power it works. No deadbatteries, no crawling around the house looking for something I can relieve of it's 9V block to get mymeter going. This inevitably means something else in the house would have no battery (e.g. TV remote, fire alarm) and it would stay that way until I remember to get some new ones in (we're talking weeks here...)

author: ThunderSqueak
author_rank: Unknown
timestamp: July 29, 2010, 07:13:56 am
content: I always preferred to just use a hand-held meter, but then I am usually all over the place fixing stuff, from southern Arizona to the northern slope of Alaska. Also, when you consider all the cables I have running all over the place on my bench, having yet 1 more would just be too muchAccuracy? Resolution? meh, my Fluke 87 and my Fluke 87V are more than sufficient :>Worried about batteries? Don't be, and if you are, keep a few around. Batteries are something you should always have on hand anyway ^^ If you don't.... shame on you o.oGet a good hand-held meter with a good tilting bail, use it at home, use it other places, put it to work and make it pay for itselfThat little BK 2709b that dave reviewed looked like a great place to start if you don't want to spring for a fluke/agilent/dranetz.

author: EEVblog
author_rank: Unknown
timestamp: July 29, 2010, 08:08:00 am
content: Quote from: david77 on July 29, 2010, 06:51:52 amI knew someone would mention that.If you get a good meter it should have many hundreds of hours battery life, and for a lot of uses that years worth of use.And you get a low battery warning where the meter is usually still usable for a while.So unless you ignored the low battery warning then you should never be stuck with a meter that doesn't work because of a flat battery!Dave.

author: squeezee
author_rank: Contributor
timestamp: July 29, 2010, 08:19:57 am
content: Quote from: BBP on July 29, 2010, 04:56:29 amHere's a link to the meters in question (TTI). Comparing specs and looking at the prices (without CAL) on RS which are 205GBP for the 1604 and 310GBP for the 1705, i'd say you're not really saving much (or getting more for your money) compared to a major brand meter.In particular you could get a handheld like the Fluke 87/V or Agilent 1252B for 300-330 pounds.If you're set on a benchtop meter there are the 'budget'3400 seriesAgilents, the U3401A for 290GBP or U3402 for 379.

author: BBP
author_rank: Newbie
timestamp: July 29, 2010, 10:52:14 am
content: Thanks for the replies guys.Seems there is little to recommend the bench meter over a handheld for the majority of requirements.I can see that those who work requires moving from one job to the next that a handheld is best. My thinking was similar to David77 in that 99.9% of what I will do is going to be at the bench. I was also thinking that maybe a bench meter had some other benefits, over a handheld, apart from being mains powered that is.@Thundersqueak, it is not that I am unable or unwilling to spring for a Fluke/Aligent etc. It was more what was the better fit for my needs. Which at the moment I will admit, are not clearly defined. I mean, I am an IT nerd by profession, not hardware anymore, more Internet gateways and computer forensics. So am getting back into microcontrollers etc. I am also getting back into ham radio, so I have a need for gear for that. I'd like and RF test set, but they are way out of my price. Keep checking fleabay though.Actually I have been perusing the Agilent site and it would seem that the U1252B might suit. I am looking at CNC'ing my home lathe and mill it has some features I would find more useful than the 87V. I also read that other thread re Agilent or Fluke.cheersRobin

author: saturation
author_rank: Super Contributor
timestamp: July 29, 2010, 12:14:52 pm
content: A used lab grade bench meter usually can be had so cheaply that it might offset its inconvenience. However, to choose one properly, one has to know a bit about electronics to avoid getting damaged ones.

author: saturation
author_rank: Super Contributor
timestamp: July 29, 2010, 02:37:59 pm
content: A bench meter is better at making an automated test station that is fed to multiple devices and a logging PC, so you can churn out measurements like a factory, keep track of the values, and generating paperwork. It also is capable of the highest accuracy, say as a voltmeter. But often, high accuracy measurements require careful or more involved set ups, because little things start to matter like the length of the leads or in ohms the need for 4 wire leads, so one tends to do such things in a controlled setting like a lab.Quote from: shafri on July 29, 2010, 01:34:47 pm

author: david77
author_rank: Frequent Contributor
timestamp: July 29, 2010, 03:45:36 pm
content: QuoteDave, I knew you'd say that.But my points still stand. And I'll add another one or three:1. It's always there. The handheld job gets thrown around somewhere and is not willing to show up when I need to make THAT ALL IMPORTANT measurement. Yes, I'm kind of a messy guy.2. You'll need more than one meter anyway sooner or later. (You should know...) So why not also get a bench meter?3. It just looks cool to have that thing sitting there. Yup, I'm a nerd I like that sort of thing.David

author: MTron
author_rank: Regular Contributor
timestamp: July 29, 2010, 04:10:03 pm
content: If your starting out...handheld for sure, bench is more specialized techOnce i started getting deeper into electronics i picked up a good handheld instead of the cheap Chinese ones i have been using. Got myself an Amprobe 34XR-A, and i love it!On a side note, Dave, my 34XR-A doesn't seem to have that sickly sounding beep yours does....maybe it just sounds worse through camera...but mine is pretty standard sounding.Other issues are the same..long latch time for the continuity, beeps when changing mode, no Rel function....But i still love the meter! (got it long before Dave's $100 shootout)Go for the nice handheldMatthew

author: Unknown
author_rank: Unknown
timestamp: July 29, 2010, 07:09:47 pm
content: Depends a lot on the type of work and your bench setup. No argument that portability can be a major factor, but I do use a bench meter for most of my 'work' (hobby). Advantages in my mind are power source (a handheld will either power off after a few minutes, or run down the batteries if I forget to turn it off). A bench meter will stay on for hours. Another issue is the display: a large LED or VFD display is much easier to read than reflective LCD in my opinion (again caused by the power source, no way to run a VFD on a battery for any amount of time). Push buttons also work better than rotary switches with one hand. Plus they stack nicely with other instruments like power supplies and function generators, so they don't take up that much space on my bench. You can get good accuracy for a lot less money (plenty of used Fluke/HP/Keithley 4.5 digit ones for <$50 or so, you'd need a Fluke 87 to get that in a handheld).But I'm talking about used bench meters from brands like Fluke and Keithley, I think most new ones for <$500 or so are crap. A disadvantage are that they're usually more bare-bones, you'll rarely find capacitance or even diode ranges on many bench meters, so I wouldn't recommend it as only meter. A used brand-name bench meter for <$100 or so can be very good value in my opinion.

author: Unknown
author_rank: Unknown
timestamp: July 29, 2010, 08:20:47 pm
content: Not if you care about safety, unless you provide CAT III/IV class isolation, since the battery is typically connected to the COM jack. Ever wonder why the manual states to unplug the meter leads before changing the battery?

author: EEVblog
author_rank: Unknown
timestamp: July 29, 2010, 10:51:22 pm
content: Quote from: david77 on July 29, 2010, 03:45:36 pmI'd rather have two handheld meters than a handheld and bench meter. Twice as versatile!If you want a permanent bench meter then it can actually be better to just bolt a long battery life handheld meter to your rack or whatever. Cheaper, no extra power point required, and doesn't take up valuable shelf space.Sorry, but unless you are doing some form of measurement that benefits from a higher precision bench meter, the advantages are not really tenable. But as always, YMMV.Yes, your points still stand, but that doesn't make them strong and convincing points!Check out the Fluke 37, a bench meter with long battery life. No power point required.Dave.

author: Unknown
author_rank: Unknown
timestamp: July 29, 2010, 11:34:01 pm
content: Quote from: EEVblog on July 29, 2010, 10:51:22 pmCheaper? Random example:Fluke 8600A that failed to sell for $10 that looks like it works fine, R/DCV/ACV/DCI/ACI, true RMS, autor-ranging and LED display(no preference for this particular model or seller). And this is a fairly normal price for those. Show me a handheld with similar quality and features for less, used is obviously fine. Even a used Fluke 73, which has less features (not True-RMS and no low current ranges) sells for more. Low-resolution (i.e. 4.5 digits or less) bench meters are not in high demand because you can get similar performance in high-end handhelds like the Fluke 87, so they are often cheaper, while used high-end Flukes are in fairly high demand (I think a used Fluke 87 still fetches $100+). Bench meters are also less likely to be abused since they don't tend to get dropped as often (although there are some trained gorillas working in some electronics labs).

author: NiHaoMike
author_rank: Super Contributor
timestamp: July 30, 2010, 01:26:01 am
content: Quote from: shafri on July 29, 2010, 07:28:00 pmVery easy. Just find a small AC adapter that outputs a measured 9V or whatever, and wire it to a 9V battery connector or whatever connector you need. No permanent modifications needed, except maybe a notch in the casing for the wire. Some "classic" Flukes like the 8021B even have AC adapter connectors.There are also those (very expensive) "wireless" power adapters for cell phones and stuff. Maybe one of those can be modified for install in a multimeter. Not sure if it might cause interference but I would expect a good meter to be extremely resistant to EMI.

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2010, 01:54:35 am
content: Quote from: alm on July 29, 2010, 11:34:01 pmWhen I said cheaper, of course I'm talking about new meters.Yes, you can get very good bargain on 2nd hand bench meters.It's simple really. If you like a bench meter and it works for you, then great, go for it.But personally I find them a real PITA.I have a HP bench meter in my lab, and another Goodwill one sitting up in cupboard. They don't get used, why?, because I simply find them less versatile than a handheld meter. Instead of the battery dying on a handheld I find it much more common for a bench meter power cable to go missing!I hate having to probe my circuit and then look up on the instrument rack to get the reading, it's annoying. Much better to sit your handheld meter next to your circuit and just glance sideways slightly.There are many reasons why bench meters are not common these days, just look ta how few there are on the market compared to handhelds. Handheld meters have been able to match the precision of bench meters for many decades now, and the long battery lives makes that point pretty much moot.Dave.

author: BBP
author_rank: Newbie
timestamp: July 30, 2010, 02:31:54 am
content: well, I never thought this would go more than a page.I did not think the subject was that emotive.I really appreciate the responses, nothing like real world experience.QuoteFor me that is the one major advantage that a handheld has on the bench is that one can position it, so that a glance is all that is needed to see the display. I have more than once fried something because I had to crane my head around something to see the meter.It looks likely that I'll get an Agilent 1252 handheld. Not sure whether the A or B. The only diff I can see is the colour and back-light. I'm leaning towards the A, as I'm not sure about that orange back-light. The A looks more blue/white in the pics. Unfortunately the closet agent in Sydney has only the A in stock and I am a bit too far south to go there without seeing both. Seems most of their stock in in Adelaide. Anyway the 1252 has a lot of features. Plus it is currently, substantially cheaper than a Fluke 87V from the local Aussie Distributor. I like the 87V, but a diff of over AU$300 swings it Agilent's way.I will see how we go with the 1252. Hopefully the 36hr battery life will not be an issue for me, shouldn't be as I won't use it everyday. I can then relegate the old meter to the car toolkit.Btw, here's one for the Fluke fans. A while back a couple of the guys at work were installing some Cisco DWDM optical networking kit. Something was up with one of the power supplies, so they decided to check the voltage on the input connector to the device. These things have redundant power supplies, which put out 48V, 3KW capacity I think. Anyway they managed to short out the power connector with the meter probes. Big flash, and most of the probe was gone along with half the Vcc connector on the cable. The Fluke survived, sans probe, and being thrown halfway across a data center in fright. Very funny since I was not holding the meter or the cable. Just lucky it was only 48V. No electrical or electronic experience mind, these were network dudes.CheersRobin

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2010, 04:04:27 am
content: Australian dealers are very expensive. Have you considered buying from overseas online?Dave.

author: BBP
author_rank: Newbie
timestamp: July 30, 2010, 04:42:22 am
content: Hi Dave,Yes, I have. In this instance I'll use Tequipment for a U1252B.US$410Freight US$69(middle of the 3 available)exchange rate approx 0.89 Aus to 1 US$Approx AU$528 landed. And I will assume I won't pay any GST/Duty.Australian price from Agilent.com.au via Aus distributor Trio SmartCalAU$531 + gst= $584inc plus $25 shipping.Close enough that I probably think getting it local and saving any possible hassle with lost goods/customs, or whatever, is better. Plus possible warranty issues.This is just this for this example. I believe Agilent a doing a special price at the moment.Whereas the 87V is around AU$800 + gst. Therefore a much better option is to buy from OS.I do have concerns regarding warranty on stuff though. What issues have you had with stuff bought online and had to have it fixed under warranty?. Or have you not bothered. I don't really care to have to send it back OS to get fixed. The reason I normally don't buy direct from China. But as they say YMMV.RobinI

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2010, 05:23:41 am
content: I've never had to deal with warranty, my stuff rarely fails (touch wood).There is no duty on stuff under $1000 into Australia.Dave.

author: jahonen
author_rank: Super Contributor
timestamp: July 30, 2010, 10:14:12 am
content: Quote from: david77 on July 29, 2010, 03:45:36 pmI know what you mean. I have been considering getting one for complementing my Fluke 89IV, which has a battery life of 72 hours. The "holy" Fluke 87-V seems to have 200 hours, so it is a bit better in that respect.In addition, with bench DMM that irritating auto-power off won't kick in just at the moment you are measuring something, like if you want to keep an eye to something for a several hours. And if you disable that auto power off, you almost certainly forgot to turn the meter off and then the battery is gone in no time.Secondly, at my work, bulky form factor and complex appearance is a bonus, since people don't "quickly lend" the meter for a random measurement and then forgot to return it... (no meaning of course if it is your personal one)Third point on my list is that if you want to make automated measurements with directly to the computer using something like Excel (you can use VBA to control your DMM!), not many handhelds can do that. 89 IV is a logging DMM, but somewhat limited what you can do with bench DMM connected to a computer via GPIB, ethernet or RS-232 etc. I remember a case when we used Agilent 34401A as an thermometer in a climate chamber test, which measured also the frequency of an oscillator. We quickly put together a software which logged a frequency using frequency counter (Can't remember the model number but Agilent one also) and resistance reading from a NTC with a Agilent 34401A, using a GPIB interface. Then a nice graph was produced where frequency was plotted as a function of temperature.Fourth thing is that if you want to measure low resistances reliably (say, R < 1?), then 4-wire resistance measurement is a must. Zeroing 2-wire measurement seems somewhat unreliable for my taste and tends to drift quite quickly.Regards,Janne

author: saturation
author_rank: Super Contributor
timestamp: July 30, 2010, 10:29:46 am
content: Interesting you folks mention this, its exactly what I use it for too, and prefer a bench meter for, continuous monitoring. I also use a scope on its slowest trace, does the same but not as accurate.Quote from: alm on July 29, 2010, 07:09:47 pmQuote from: jahonen on July 30, 2010, 10:14:12 am

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2010, 10:36:47 am
content: Quote from: jahonen on July 30, 2010, 10:14:12 amIt's speced at 400 hours actually.The 28-II has 800 hours.Curiously I wonder which meter has the best battery life these days?The old Fluke 25/27 used to have 1000+ hours.QuoteWe've got some Uni-T bench meters at work, and they are notorious for their auto power off. Absolutely horrible to use.Once again, not really a problem if you get a decent meter with say 400+ hours. One 24 hour forget to turn-off isn't the end of the world.QuoteYes indeed, no one wants to borrow your bench meter (guess why! :->)I've found that slapping a "broken" sticker on gear helps prevent pilfering!QuoteSure, bench meters are nice for proper long term logging measurements.QuoteYeah, 4 terminal is better for that, if you've got the probes.Dave.

author: jahonen
author_rank: Super Contributor
timestamp: July 30, 2010, 11:31:59 am
content: Quote from: EEVblog on July 30, 2010, 10:36:47 amSo it seems after all, I wonder where I got that 200 hours figureRegards,Janne

author: Unknown
author_rank: Unknown
timestamp: July 30, 2010, 01:17:23 pm
content: Quote from: EEVblog on July 30, 2010, 10:36:47 amI would have expected something really basic like a Fluke 12, but the Fluke 12E is rated for just 200 hours. Something modern with a simple ASIC (but not the ancient ICL7106). Accuracy, features, powerful MCU's and fancy displays tend to suck power. Basically the opposite of the Fluke 80-IV/180/280 series. I checked a few candidates, but couldn't find anything better than 800 hours, 400 hours appears to be standard. The Fluke 17B is 500 hours, which is at least better than the 87-V.

author: StephenOng
author_rank: Newbie
timestamp: July 30, 2010, 01:23:27 pm
content: Quote from: EEVblog on July 30, 2010, 10:36:47 amFluke 77 III has an awesome 2000 hours battery life

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2010, 01:38:02 pm
content: Quote from: alm on July 30, 2010, 01:17:23 pmI know I've seen a current model meter somewhere that does 1000+ hours, but for the life of me can't think of it!One of the more obscure brands maybe...My Gossen MetraHit World does 750hours from 2 AA's.Dave.

author: jpb
author_rank: Super Contributor
timestamp: May 16, 2014, 03:21:23 pm
content: Quote from: EEVblog on July 29, 2010, 05:32:31 amDave,Sorry to raise an old thread, but I'm curious to see if you're view has changed since you acquired your Agilent 34461A?I currently have a nice Advantest 5 1/2 digit I got cheap on e-bay and a surprisingly accurate (at least it agrees well with my Advantest) handheld meter I got from Maplin.I want to get another meter that is of the same order as the Advantest - I'd like a 6 1/2 digit but they are a little pricey - and am looking at high end handhelds vs mid range (5 1/2 digit) bench.The trade off is versatility/robustness of the handheld versus increased accuracy (of the order of a factor of 4 or so)/no batteries to worry about/larger brighter display of a bench top.I want to buy new so I get a calibration point to compare my older uncalibrated meters with.What are people's latest views?

author: electr_peter
author_rank: Unknown
timestamp: May 16, 2014, 08:04:55 pm
content: I am with Dave that handhelds are much more versatile and more useful all around, except maybe for super high accuracy and long term logging applications. Benchtops contains mostly empty space (due to "box" size constraint) and adds additional cable to trip on.Concerning power options. Only cheap meters do not have auto power off feature. Proper meters have settable APO (or just turn off APO is it is not needed).One point I did not find in posts above is power outage. What can you do with benchtop meter if there is no mains power? Nothing, you are left with 0 functionality. Handheld has inherit advantage of versatility in such situation.

author: AG6QR
author_rank: Frequent Contributor
timestamp: May 16, 2014, 09:23:44 pm
content: Quote from: jpb on May 16, 2014, 03:21:23 pmI doubt things have changed much since the original thread. That kind of accuracy is rarely needed for general electronics work, though I'll cheerfully admit there are times when it can be useful. And I can admit to having a twinge of volt nut fever myself sometimes, wanting more accuracy than I really need. Truthfully, it's rare that I genuinely need more than two and a half digits, but I'm glad to have more.For most purposes, the flexibility of a handheld wins hands-down. But a bench meter still has some advantages.In a school lab, bench meters aren't as likely as handhelds to "walk out the door" in someone's pocket. This is less of a concern in a private setting, but sometimes it's nice to know that the meter stays on your bench.Bench meters are available with more digits than handheldsBench meters never suffer a dead battery. True, handheld ones rarely do in most use cases, as was already pointed out earlier. But there are special cases like long term data logging where it's nice to know a long experimental run won't be interrupted by a dead battery or auto power off.Bench meters can have nice lighted displays, since they're not dependent on battery powerI'm just glad it doesn't have to be an either/or proposition. Nothing wrong with owning both!Quote from: electr_peter on May 16, 2014, 08:04:55 pmDuring a power outage, my power supplies, oscilloscope, signal generator, soldering iron, and lots of other devices won't be working. So I'm unlikely to use a meter for much, except perhaps diagnosing whether the problem is mine or the utility company's. For that purpose, a test lamp is sufficiently accurate. But you do have a point, I sometimes use a handheld meter far from utility power, for example for automotive diagnostics in the field.

author: jpb
author_rank: Super Contributor
timestamp: May 16, 2014, 09:27:32 pm
content: Quote from: electr_peter on May 16, 2014, 08:04:55 pmSpace is a negative for bench DMMs, it is a bit like the comparison between desktop and laptop computers - laptops are smaller and portable but they cost more for a given power (or in this case given accuracy level). I have lots of sockets on my bench so tripping over a cable isn't an option in my case. Display wise the modern bench units have much bigger and clearer displays than battery powered portables but then a handheld can be placed close to the work and looked at more easily so this is probably a draw.Quote from: electr_peter on May 16, 2014, 08:04:55 pmAPO I tend to find annoying as you have to keep waking the thing up.As AG6QR said (he posted just as I was typing this) If there is no mains power, then my scope, power supply, lights, soldering iron and so on wouldn't be working anyway so I'd probably give up and do something different anyway - but I can see if I wanted to test voltages on a car or in an external active antenna or whatever then the battery powered meter is the only option.

author: jpb
author_rank: Super Contributor
timestamp: May 16, 2014, 09:36:37 pm
content: Quote from: AG6QR on May 16, 2014, 09:23:44 pmI already have both, though my handhelds are an ancient analogue and a Precision Gold from Maplin. My bench is a 5 1/2 digit from e-bay that I recapped and it seems to work well but I've never had it calibrated.I thought I would invest in a good meter. But given that; I can't decide whether this is an opportunity to go for a new bench that will be calibrated and possibly more accurate than my e-bay Advantest or go for a less accurate but more versatile solid handheld.

author: nanofrog
author_rank: Super Contributor
timestamp: May 16, 2014, 09:58:54 pm
content: Quote from: jpb on May 16, 2014, 09:36:37 pmYou'll probably get more use out of a solid handheld, and the convenience is nice to have as well (less bench space and no power cord to fuss with). Worst case and you want top accuracy without going crazy on price, look for a 50k count model, such as a Brymen BM869 from tme.eu (Gossen makes a 1.2M count model, but it's very expensive).You might also want to consider a DMM Check Plus to check your existing meters against, and doesn't cost a fortune (less than half the calibration fee for one meter based on US cal pricing).

author: jpb
author_rank: Super Contributor
timestamp: May 16, 2014, 11:18:33 pm
content: Quote from: nanofrog on May 16, 2014, 09:58:54 pmThe Gossen 1.2M model is actually reasonably priced in that it is about the same (slightly cheaper) than the Agilent 34461A with very similar accuracy specs (in fact slightly better) but it is rather limited in that it only measures up to 100mA but it does do 4 wire resistance measurements. A more sensibly priced and versatile one is the Gossen Ultra which is 300k count though it is around 2-3 times the error spec of my 5 1/2 digit (so it is not as good as a 300k 5 1/2 digit bench meter) - but it is a proper CAT IV meter with AA batteries and a 10A range, capacitance and other measurements. The price of the Ultra without the interface module is more than a Fluke 87V but not much more (Fluke is around £410 inc VAT and the Ultra is £470 whilst the M30 is £840!!).I'm planning to get the 0.01% Voltage reference from Doug rather than the DMM check plus - I'm not so bothered by AC and I'm working on a GPSDXO which I can use for frequency and I'll probably get a Vishay resistor or two for resistance and current. If I buy an new meter (a Gossen at least) then it comes with a detailed calibration and I can use it to check my existing meters.

author: nanofrog
author_rank: Super Contributor
timestamp: May 17, 2014, 12:42:24 am
content: Quote from: jpb on May 16, 2014, 11:18:33 pmCompared to new benchtop units, the M30 does offer value. But I still see it as pricey for a handheld, and it's possible to get a 6.5 digit bench unit via the used market for a lot less.FWIW, my U1252B is capable of 4 wire measurements.Quote from: jpb on May 16, 2014, 11:18:33 pmI thought Doug stopped making his, leaving either the DMM Check or other units available on eBay.

author: cellularmitosis
author_rank: Unknown
timestamp: May 17, 2014, 01:28:25 am
content: Here's a perspective from someone who has been a hobbyist for a couple of years:Bench or Handheld, get meters which have serial out / GPIB / whatever. You won't need this functionality yet, but a couple of years from now you might wish you had it!I've been slowly working towards being able to characterize parts by sweeping one parameter, etc. I want to be able to hit "enter" on my keyboard and have a script do the rest. Fun! Up until now, I had to take data manually: tweak the knob, take a photo, repeat, then dump it all into excel.Frankie (a forum user in china) sells two handhelds which are decent and both feature serial out. One it a bit higher precision (but not accuracy) than the other, and they are both pretty cheap for what you get ($54 and $37 USD).http://www.ebay.com/itm/UNI-T-UT-61E-UT61E-22-000-count-Digital-Multimeter-/200901686717http://www.ebay.com/itm/Digitek-DT-4000ZC-TekPower-TP4000ZC-Data-Logging-Multimeter-with-Temperature-/200912705694Eventually you will want four multimeters (you need four to characterize the efficiency of a power supply). If I had to start over with acquiring gear, knowing what I know now, those four would probably be:* ($37) One of frankie's Digitek DT-4000ZC* ($54) One of frankie's UT61E* ($150) A vintage 5.5 digit bench meter with GPIB or serial (e.g. the HP 3478A)* the fourth would either be another Digitek DT-4000ZC or another, but different manufacturer 5.5 digit bench meter.Having a variety of meters like that is a good thing. Typically, if you are measuring and logging several variables at once, it is likely you only need uber precision on just one of them, so having one really high-end (5.5 digit) meter is nice. Having different makes of meters will give you a good picture into measuring their drift against each other (this is why it would be nice to have two 5.5 digit meters).

author: jpb
author_rank: Super Contributor
timestamp: May 17, 2014, 09:39:01 am
content: Quote from: nanofrog on May 17, 2014, 12:42:24 amHe still has them on his web shop - I've not looked on eBay:http://shop.voltagestandard.com/product.sc;jsessionid=3D61DFF47B5BCBB2B42273295C4E96DF.m1plqscsfapp03?productId=1&categoryId=1The other advantage of the Voltage reference vs the DMM check from my point of view is I can order one at 3V instead of 5V which fits in with my 5 1/2 digit meter (the calibration points are 300mV, 3V and 30V so combined with a 10:1 divider I can check at 3 points (using the 3 matched resistors in parallel and series trick by the person whose name I forget - as described on Geller labs site - a great shame he's stopped selling his 10V reference):http://www.gellerlabs.com/752AJunior.htmI'd love to get Doug's 5V 0.0025% reference but I'm in the UK so I have to pay VAT/import duty plus shipping and the cost is already $280 plus I wouldn't really be able to send it back for recalibration without risking having the customs people charge me import duty all over again (plus the expensive shipping).

author: jpb
author_rank: Super Contributor
timestamp: May 17, 2014, 10:14:15 am
content: Quote from: cellularmitosis on May 17, 2014, 01:28:25 amA good point. One thing that annoys me about my WaveJet scope (which is otherwise excellent) is that I got an early model without USB control port (it actually has one physically present but it can't be used) and the cost of adding a LAN connection is £400!! ($600 in your money!!). I've been getting repetitive strain injury having to manually save the 1024 history screens to USB stick one at a time!My Advantest 5 1/2 digit meter has serial (USB) connection built-in and also has two ports so can be used to characterise devices (i.e. measure Voltage and current at the same time) and my cheap DMM has USB connectivity but I've not yet used these features.One thing that Dave pointed out about Gossen meters is they charge a fortune for the simple IR - USB serial lead (£180 inc VAT) and for the power adapter (around £100 inc VAT) plus even more if you want their software. Their Ultra meter can be got with Bluetooth and that is a more reasonable £60 to £70 extra.Quote from: cellularmitosis on May 17, 2014, 01:28:25 amMy thoughts were to try and combine getting a good portable meter with one that is on a par with the 5 1/2 digit so I could both have a really good handheld and be able to check the high resolution meters against each other.The closest I can find is the Gossen MetaHIT Ultra which is 300k count i.e. should be a 5 1/2 digit but its noise floor is quite high at 25 microVolts and so though its headline dc error is 0.02% which is just a little bit more than the 0.015% typical of a 5 1/2 digit, when the overall error is taken into account it is about 2 1/2 times worse (0.052% versus 0.021% of my Advantest). Still pretty good though being a factor of 2 up on say a Fluke 87V or Agilent U1273A.Having the accuracy at least of a 5 1/2 digit is important to me as I've been working on a GPSDO and I need to adjust the frequency pulling voltage down in the 10s of microVolts if not microVolts range when doing my manual experiments - absolute accuracy is not so important but being able to make very small adjustments and have stable readings is important. I'd really like to get a 6 1/2 digit but the price is getting a bit high. The difference between 5 1/2 digits and 6 1/2 digits is not that large - it works out at about a factor of 4 rather than 10.

author: nanofrog
author_rank: Super Contributor
timestamp: May 17, 2014, 06:03:48 pm
content: Quote from: jpb on May 17, 2014, 09:39:01 amGot Doug mixed up with Joe Geller (ceased sales).Quote from: jpb on May 17, 2014, 09:39:01 amShame the PentaREF doesn't have the level of accuracy the Voltage Reference does (more convenient if it did).

author: mzacharias
author_rank: Frequent Contributor
timestamp: May 18, 2014, 04:05:47 pm
content: I have lots of really good handhelds, but I wouldn't want to be without my Fluke 8840A. Aside from the really nerd-cool NASA cal sticker, I occasionally do benefit from the extra resolution. For example, when cleaning / checking relay contacts, I can rel out (offset) the OHMS and measure contact resistance down to the milliohm level without even going to 4-wire, which is a pain if the connection pins on the relay are small, which they always are. I'll admit I practically never really need the full 5 1/2 digit resolution on voltage, but who among us really does? Aside from those of us who are really into solar cells and ultra capacitors, I suppose...Still, for day-to-day use, I have to concede handhelds are best in most situations.

author: saturation
author_rank: Super Contributor
timestamp: May 19, 2014, 12:20:53 pm
content: Summarizing features of bench vs handheld the most unique item in benchmeters remains the highest available accuracy and precision. Bench DMM that look like a bench meter but have features, accuracy and precision of a HH are a waste of space, IMHO, unless they are sold at a substantial discount pricewise.In the past 10 years, built in trend capture has been a timesaver I wish I had, each time I truly need one I rig up my laptop for realtime data capture and plotting or setting the scope on roll mode, having that feature saves me setup time and I'd use it nearly all the time.There are a few metrology grade benchmeters that would sell for $100 typically in the USA [ range $50-200 working, $300 with cal certificate FWIW] that would be worth having for the accuracy and precision, for any lab wishing so but can't justify the cost of a 34461a or similar. Those would be the HP3456a and HP3455a, both are DVM. The HP3457a is a full DMM, is about $200-500. The DC accuracy of the 3456a is overall better than the new 34461a. You can find spec sheets online.There are many used non-HP metrology grade DMMs but the problem are spare parts to keep them working. What I did over 2 years was buy 4 3456a working, assuming some would die along the way. 4 years later, one died that I keep for spare parts or repair as needed, while 3 remain working and calibrated, and I paid about $100 for each on average, cal included.