Looking for a bench multimeter - Page 1
Forum section: electronics / testgear

author: unimorpheus
author_rank: Regular Contributor
timestamp: February 02, 2016, 09:47:46 pm
content: I was originally considering the Rigol DM3000 series but the price for the 6.5 digit does not appear to be that competitive. I have been looking at Agilent, Keithley and Fluke and have been leaning toward Fluke only because I have/had 6 or so Fluke handhelds over the years. What I don't understand is the myriad of Agilent models both new and old. Can anyone provide some assistance on working out Agilent and Fluke bench DMM model numbering. I have been looking on eBay for some good used gear but I am not familiar enough with this gear to know good from bad. Not really sure if I really need 6.5 digits when 5.5 may be fine. Also what is the real dig against the Rigol meters? I currently have the DS2072a, DG4062 and DP832 that needs calibration hence the bench DMM. I don't think my Fluke 179 or twenty year old Fluke 87 series 1 is up to the task. Any advice would be welcome.

author: nidlaX
author_rank: Frequent Contributor
timestamp: February 02, 2016, 11:54:49 pm
content: Here are some common Agilent / Fluke / Keithley multimeters to look for off the top of my head:6.5 digit bench form factor:Agilent 34401AAgilent 34411AFluke / Tektronix DMM4040 / 4050Keithley 196 (Vintage)Keithley 2000 / 2015 / 27006.5 digit rack form factor:HP 3455A (Vintage)HP 3456A (Vintage)HP 3457A (Vintage)Keithley 193 (Vintage)Keithley 2700 in a rack enclosure5.5 digit bench form factor:Agilent 34450AFluke / Tektronix DMM4020Fluke 8800A / 8810A (Vintage)Fluke 8860A (Vintage)HP 3468A (Vintage)Keithley 199 (Vintage)If you get a meter that's described as used / untested, I would recommend searching the repair forum for potential issues that may be present.

author: TheSteve
author_rank: Unknown
timestamp: February 03, 2016, 12:30:35 am
content: You can also add the following Keysight (Agilent) 6.5 digit meters:34460A34461A - more or less the sweet spot in the new line of meters that offers the most bang for the buck.34465Abtw, I am not sure about a "dig" against Rigol meters but at the end of the day do you want a meter made by a chinese company that offers less support and has no history of top of the line commercial test equipment or do you want something made by Fluke/Keithley/Agilent/Keysight that have decades of proven performance?

author: billfernandez
author_rank: Regular Contributor
timestamp: February 03, 2016, 01:00:57 am
content: Quote from: TheSteve on February 03, 2016, 12:30:35 amI recently bought this one. I wanted a (to me) high precision, flexible, general-purpose bench meter. I wanted to have confidence (yes confidence is an opinion, not an objective fact) that it would be reliable, long-lived, well-characterized (for when I really needed to get particular about measurement). I wanted it to be a "modern" design with the implication that it would have modern features. This one has Ethernet connectivity, built-in web server, BenchVue software for remote programming, compatibility with SCPI programming, and the ability to do things my old meters could never dream of, such as data-logging and graphical display of histograms, etc.It's not the only meter on the market with these kinds of characteristics, but as TheSteve said, it's kind of a sweet spot in the contemporary bench meter market.

author: nctnico
author_rank: Super Contributor
timestamp: February 03, 2016, 01:06:15 pm
content: I looked at Tektronix (Keithley) DMMs but I'm leaning towards the Keysight 34461A as well. The Tektronix DMM4040 looks just as accurate but it's input impedance is 1M Ohm where the 34461A has an input impedance of 10M Ohm with an optional >10G Ohm setting. I have run into several situations where a 10M Ohm input resistance is already too low. And let's not forget the color TFT display versus low resolutuion VFD.But looking at the OP's requirement I doubt a 6.5 digit meter is required. Calibrating a scope, frequency generator and PSU should be perfectly doable with a 4.5 (5.5 at most) digit multimeter.

author: KJDS
author_rank: Super Contributor
timestamp: February 03, 2016, 01:31:29 pm
content: I've got a pile of Solartron 7159plus 6.5 digit meters available. To be honest, they are more of a good 5.5 digit meter that displays and extra random number when asked than a true 6.5 digit meter, but they do make excellent bench meters when you do't need that last bit of resolution.

author: HKJ
author_rank: Super Contributor
timestamp: February 03, 2016, 01:52:37 pm
content: Quote from: nctnico on February 03, 2016, 01:06:15 pmWhere have you got that idea from? It has 10Mohm and >10Gohm settings.I have two 8846A (The Fluke version) and they are very stable and precise, they basically matched my new Keithley DMM7510.

author: nctnico
author_rank: Super Contributor
timestamp: February 03, 2016, 02:53:13 pm
content: Quote from: HKJ on February 03, 2016, 01:52:37 pmYou are right. I now see that was the AC specification table.

author: Muxr
author_rank: Super Contributor
timestamp: February 03, 2016, 03:08:41 pm
content: It's a personal preference, but I actually like the VFD better. It just looks better than TFT with its backlight leak. Although TFT is superior in the amount of information it can display and longevity.

author: generic_username
author_rank: Regular Contributor
timestamp: February 03, 2016, 03:24:56 pm
content: I have a somewhat silly question as I looked for a 6.5 Digit Meter myself in the past days.If I buy a 6.5 Digit thing used it is certainly out of calibration and there's no way I'd have the equipment to cal such a meter myself(service manual of a Agilent 34411A states a Fluke 5720A )So why should someone for hobbiest purpose getting a 6.5 digit meter ( although the used ones are fairly cheap)

author: nctnico
author_rank: Super Contributor
timestamp: February 03, 2016, 03:32:53 pm
content: You can always choose to send a DMM in for calibration. No idea about the costs though but it must be less than a new DMM to make sense. Calibration costs will also depend on how difficult it is to calibrate the instrument.

author: Muxr
author_rank: Super Contributor
timestamp: February 03, 2016, 03:54:20 pm
content: Quote from: generic_username on February 03, 2016, 03:24:56 pmIt's a risk you take when you buy second hand. I have a few voltage standards I use to check all my meters, like the DMM check plus, they aren't anything fancy, but it's good enough just to see if you're close enough, also ok for calibrating old 4.5 meters or oscilloscopes.You also use your other meters to compare. Some folks may use a calibrated 6.5 (or higher res) meter they own and trust to be in spec to calibrate their other meters. There are also profesional voltage transfer standards you can calibrate and use to calibrate your other gear.DMM check is useful as It basically just gives me a warm and fuzzy that the instrument is not horribly out of spec. I don't have a need for a 6.5 digit meter really, 5.5 is overkill for most stuff I do. The one I own I got it for the THD measurements (keithley 2015) the 6.5 resolution came as a bonus. My Fluke 87 Vs is what I measure voltages with most of the time, and it's good enough.A meter may not be calibrated, but it can still provide good enough drift measurements if you're trying to measure drift in a circuit over a period of time with a higher degree of accuracy because 6.5 digit meters will have an oven controlled reference with little drift.

author: HighVoltage
author_rank: Super Contributor
timestamp: February 03, 2016, 04:20:53 pm
content: I would vote for the 34401A if you want to save some money on a used meter.There are plenty around and many times cheap.Usually the 34401A stays very stable even years after the last calibration.And if you don't need the last digit, most likely a used one will fulfill your need for accuracy.In normal setting, when you turn on the 34401A it is in the 5 1/2 digit mode anyways, not even showing the last digit. I have bought many 34401 meters used on ebay and when they are not broken, they are usually within the Agilent 1 year specifications. Even more interesting, when I bought broken units and repaired them, many of them were afterwards within specifications as well.

author: Fungus
author_rank: Super Contributor
timestamp: February 03, 2016, 04:28:52 pm
content: Quote from: generic_username on February 03, 2016, 03:24:56 pmBragging rights?

author: TiN
author_rank: Super Contributor
timestamp: February 03, 2016, 04:31:16 pm
content: Bench DMMs are fun. Even if it's not calibrated but working properly, you still can benefit from 6.5 digits, using ratio measurements and comparing signals. Calibration is required only if you need to know absolute reading accuracy.

author: Fungus
author_rank: Super Contributor
timestamp: February 03, 2016, 05:25:21 pm
content: Those things are designednotto drift.Even if it hasn't been calibrated for ten years it's probably still OK for hobby use.Calibration certificates are mostly for people who need to cover their asses in legal-liability situations.Realistically, how often will you need make an absolute measurement to six digits? Not very often (maybe only for calibrating other instruments...)If you want to watchchangesin measurements then it doesn't have to be perfectly calibrated. I'd say this usage is more common for 6.5 digit meters than absolute measurements (eg. measuring ppm temperature coefficients, watching a battery draining...)

author: saelig
author_rank: Contributor
timestamp: February 03, 2016, 08:09:47 pm
content: We have the Siglent 5 1/2 digit DMM SDM3055 on sale if that helps .... We have two in stock now.http://www.saelig.com/product/M00110009.htmAlan LowneCEO Saeli Co. Inc.

author: trevwhite
author_rank: Frequent Contributor
timestamp: February 03, 2016, 08:27:15 pm
content: I did get it cheap from Toploser but my Keithley 2110 performs really well. People noted the display was a bit flaky but it is actually only when first powered up that it's contrast appears a bit faded. After a few minutes the screen 'warms up' and is nice and clear. But even when first powered on the screen is fine. I used it just today with dual readings to monitor a battery being charged. I was able to monitor the voltage and current and log the readings together via the USB with the Keithley software. The software is not great but it has worked. I have a CSV file with all the data.I think Keithley rebadged this meter from another company. Array? What I noticed was that Array sell it as a 6.5 digit meter whereas Keithley have chosen to sell it as a 5.5 digit. This makes me think Keithley did their homework on this meter and tested it properly before selling it on as if they just rebadged it they would have sold it as a 6.5 digit version? But I cant be sure of any of that.Anyway, it has been a really good meter. One thing that I do struggle with and this might be because I am a bit deaf is I find the continuity beep quiet. I literally have to turn my ear towards the meter to know if its beeping or not. But I do struggle with high frequency so I can not tell if its the meter or me. Probably a bit of both.I do not know what other data logging software is like but I would imagine Keysight would be hard to beat. My next bench meter will be a Keysight one but I am more than happy with the Keithley for now.

author: ECEdesign
author_rank: Regular Contributor
timestamp: February 03, 2016, 08:51:08 pm
content: I am also looking for an HP 34401A. Local calibration lab will calibrate for 90 US dollar. Hopefully there will be a nice meter for a good price in May when I can purchase. If not I guess ill go with the U1282A handheld by Keysight but for bench work I think I would prefer a benchtop meter. The handheld is much more likely to get 'borrowed'

author: ez24
author_rank: Super Contributor
timestamp: February 03, 2016, 09:03:58 pm
content: QuoteLooking at these on ebay, most if not all show a low DC voltage with no leads. Such as 0.0xx mvUsing these, is there a way to zero this out, or do you need to subtract out this number?This one shows .052 mvhttp://www.ebay.com/itm/Agilent-34401A-6-1-2-Digit-Multimeter-/172082055969?hash=item2810e3cb21:g:OpUAAOSwZG9WjH~H

author: TheSteve
author_rank: Unknown
timestamp: February 03, 2016, 09:15:48 pm
content: The voltage displayed with no input is completely normal, it occurs because the meters have such a high input impedance. If you short the input they will likely read zero or very close to it.

author: deadlylover
author_rank: Frequent Contributor
timestamp: February 03, 2016, 09:41:50 pm
content: Yep even with the 34401A in its default 10M input impedance mode, the display can show a few hundred counts with open inputs. They do have a math null function.The 34401A is fantastic value used, I know that one of my units has not been adjusted from factory since 1996 or so and it is still mostly within 1 year spec, it seems that the 10VDC range drifts 15-22ppm then slows drastically over the years.

author: TheSteve
author_rank: Unknown
timestamp: February 03, 2016, 10:28:13 pm
content: If buying used the 34401A does seem like an excellent option, if buying new I'd aim for the 34461A. I know I quite like mine.

author: ez24
author_rank: Super Contributor
timestamp: February 03, 2016, 11:15:25 pm
content: Quote from: TheSteve on February 03, 2016, 09:15:48 pmthanks

author: HighVoltage
author_rank: Super Contributor
timestamp: February 04, 2016, 09:42:58 am
content: Quote from: ez24 on February 03, 2016, 09:03:58 pmThis meter looks in excellent condition.Clean contacts in the front and rear terminalsClean and no corrosion on the rear BNCThe display seems to be nice and brightIt is a newer model, Agilent branded and red / black terminals as to all red terminals in older HP modelsIt comes with handbooksIf you can get this for $ 350 or little above, it seems to be a real good dealI would ask the seller if it passes the self-test procedureAlso, it does not come with the bumpers or handle, but those you can easily buy used or new on ebay.

author: bitseeker
author_rank: Super Contributor
timestamp: February 05, 2016, 01:45:30 am
content: I have an HP 34401A and a Keithley 2700. Both great instruments.When shopping for a used 34401A, note that the first generation of front panel uses a VFD driver chip that is no longer produced. Later units have a newer display assembly with a different driver. Also, the newer display assembly is not compatible with the older motherboard.Older display assembly: 34401-66502Newer display assembly: 34401-66512The change occurred sometime during serial number 3146Axxxxx. These units have all red terminals (not black and red). However, not all models with all-red terminals have the old display assembly. So, it can be hard to spot them without looking inside.

author: nctnico
author_rank: Super Contributor
timestamp: February 05, 2016, 06:19:24 pm
content: Quote from: TheSteve on February 03, 2016, 10:28:13 pmThe possibilities to make graphs on the 34461A (and similar Keysight models) is very appealing. Dave has shown this in some of his videos. Ofcourse you can do the same on a PC and control the DMM remotely but I like/prefer equipment which is self-contained.

author: unimorpheus
author_rank: Regular Contributor
timestamp: February 07, 2016, 01:09:18 pm
content: Wow, thanks to everyone for your valuable insight and information. I have been looking at some of the used equipment recommendations but having just resolved a bad eBay oscilloscope buy I am pretty skeptical about some of these sellers "fully functional" claims. I know the answer here, you really need to know the equipment you are considering at a very low level. Unfortunately that is not always possible with equipment you can't get your hands on the gear until after the purchase, which is why I was reaching out to the forum and you guys came through. I have learned a considerable bit about old Tektronix scopes so there is value in that which can justify the money spent.

author: unimorpheus
author_rank: Regular Contributor
timestamp: February 07, 2016, 01:14:40 pm
content: Quote from: KJDS on February 03, 2016, 01:31:29 pmI don't know why but that is just too funny.

author: nctnico
author_rank: Super Contributor
timestamp: February 07, 2016, 01:20:38 pm
content: Quote from: unimorpheus on February 07, 2016, 01:09:18 pmIf you need something second hand which works then you should buy from a seller offering at least a one month warranty and don't give feedback until the warranty period is over. It also helps to check serial numbers and see how old it is. I rather not buy equipment which is over 15 years old.

author: KJDS
author_rank: Super Contributor
timestamp: February 07, 2016, 02:08:14 pm
content: Quote from: unimorpheus on February 07, 2016, 01:14:40 pmWhen you look at the accuracy specs of most high end multimeters then the last digit doesn't mean much. That resolution can be useful for analyzing drift, but in 6.5 digit mode the 7150plus only updates every 6 seconds. With something like a 34461 or a K2000 then you could get an extra order of resolution by remote sampling over the same timeframe.For most hobbyists it provides more than enough accuracy, the schematics are available and at a third of price of a 34401 or a K2000 then it's an attractive option.

author: tooki
author_rank: Super Contributor
timestamp: February 19, 2017, 12:20:07 pm
content: Quote from: bitseeker on February 05, 2016, 01:45:30 amThe local auction site has a Keithley 2700 going for about $300 at the moment. Is this model a good choice as a general bench meter? (I've got a Keithley 197, and it works great, but the non-backlit LCD drives me nuts, I want something with a bright, clear display.)

author: bitseeker
author_rank: Super Contributor
timestamp: February 20, 2017, 04:41:29 am
content: The K2700 is a K2000 with two slots for scanner cards. So, it's an excellent bench meter and can support measuring up to 80 devices depending on which cards you get (there are also cards for matrixing devices together).Since it uses a VFD, the display contrast can be excellent, depending on how much it has faded from use. The digits, however, aren't as large as on the HP 34401A/34410A/34411A.$300 is a good price, especially if it includes at least one scanner card.

author: Wytnucls
author_rank: Super Contributor
timestamp: February 20, 2017, 07:09:07 am
content: No diode measurement and no dB from the panel, but a huge data buffer (55,000).300$ is a good price, if the unit is in good nick.

author: tooki
author_rank: Super Contributor
timestamp: February 20, 2017, 01:27:58 pm
content: Quote from: bitseeker on February 20, 2017, 04:41:29 amQuote from: Wytnucls on February 20, 2017, 07:09:07 amDoesn't seem to include any cards. (Not that I need that in any way; I just want an easy-to-read meter that doesn't use up bench space the way a handheld meter does...)Here's the listing:https://www.ricardo.ch/kaufen/handwerk-und-garten/elektrowerkzeuge/messen/tisch-multimeter-von-keithley/v/an886253932/I can't quite tell how good condition the display there is in. The unit as a whole looks decent, as far as I can tell by the shitty photos.

author: Wytnucls
author_rank: Super Contributor
timestamp: February 20, 2017, 01:52:24 pm
content: Cosmetically, it looks fine. I would ask him to run the self test to make sure internals are ok too. Those cards are expensive and seldom included.As a bonus, you get the 4-wire thermal EMF compensation and the buffer Max-Min, which the 2000 doesn't have.The display looks bright enough with image auto correction:

author: bobaru
author_rank: Contributor
timestamp: February 20, 2017, 04:46:12 pm
content: Here is a nice meter worth considering. It is a used Keithley 2015 6.5 digit bench meter with a VFD. The VFD is easy to read, but as a principle I don't like them because they dim as they age.http://www.ebay.com/itm/KEITHLEY-2015-6-1-2-Digit-THD-Audio-MultiMeter-fully-tested-w-warranty-/371582307445?hash=item5684080c75:g:2IsAAOSwSdZWfBdPThe seller is offering it as fully tested with warranty. I purchased one of these a couple of months ago and love it. One of the nice features is the built-in audio generator and the ability to measure THD making it a nice meter for audio work. Disclaimer: I have no affiliation with the seller, just a satisfied customer.-bob

author: tooki
author_rank: Super Contributor
timestamp: February 20, 2017, 07:15:34 pm
content: Yeah, the problem is that shipping and customs on that will drive up the price a lot.

author: bobaru
author_rank: Contributor
timestamp: February 20, 2017, 07:19:38 pm
content: I just checked my purchase history. There was no customs charge and $19.95 shipping to Maryland.-bob

author: GreyWoolfe
author_rank: Unknown
timestamp: February 20, 2017, 08:28:47 pm
content: Why not grab one of the GW Insteks from the ITT closure? I got one for $90 USD and it looks like it was hardly used.

author: TheSteve
author_rank: Unknown
timestamp: February 20, 2017, 08:45:48 pm
content: Grab the Keithley 2700. It is a nice meter that boots super quick and has no fan. The continuity tester is also excellent in it, you get to specify the exact resistance you want it to alert below and it is very responsive.

author: tooki
author_rank: Super Contributor
timestamp: February 20, 2017, 09:35:57 pm
content: Quote from: bobaru on February 20, 2017, 07:19:38 pmYes, but shipping to Switzerland would be a lot more, and Swiss customs will charge 8% tax on the value (item+shipping), plus a processing fee. It adds up fast.(Where in MD, by the way? I lived in the Baltimore area for about a decade!)Quote from: TheSteve on February 20, 2017, 08:45:48 pmI let the auction end (with no bids!) since the seller didn't respond to my question about whether it's in full working order yet. It's been extended by another 2 weeks now.

author: bobaru
author_rank: Contributor
timestamp: February 20, 2017, 09:58:10 pm
content: Quote from: tooki on February 20, 2017, 09:35:57 pmHi,DC area, just inside the beltway. Been in the area since '73. As for the customs amount I was thinking in terms of the OP. Yes, you would probably pay a large penalty to ship and import to you. On the other hand I believe the MSRP on this unit was around $4800 so it really is a bargain!-bob

author: tooki
author_rank: Super Contributor
timestamp: February 21, 2017, 09:48:55 am
content: Quote from: bobaru on February 20, 2017, 09:58:10 pmOh cool! My aunt used to live in Silver Spring, and her letting me move in with her when I returned from Switzerland is how I ended up in MD to begin with! <3As for the 2015, another forum member here has a 2015 he'd be willing to part with for less than what it'd cost for shipping and customs for the eBay one, so if thePrema 5017I'm looking at doesn't work out for me, I'll grab it or the 2700. (I had even considered getting a 2015 and shipping it to my friend's in Crofton for me to take back the next time I visit, as I did with the Keysight 1252Bs I got.)

author: bobaru
author_rank: Contributor
timestamp: February 21, 2017, 08:14:37 pm
content: It looks like the seller sold out of all 99 of the previously linked meters. I just checked and they still have in stock the same meter but with rack ears for 25 dollars more. Once again, I have no affiliation with the seller except for being a satisfied customer.http://www.ebay.com/itm/KEITHLEY-2015-6-1-2-Digit-THD-Audio-MultiMeter-fully-tested-w-warranty-/371553124387?hash=item56824ac023:g:a4oAAOSwWTRWvjsh-bob

author: tooki
author_rank: Super Contributor
timestamp: February 21, 2017, 09:46:41 pm
content: I decided to go with the 2015 from another forum member. Ends up cheaper than shipping + import fees from USA.

author: bobaru
author_rank: Contributor
timestamp: February 21, 2017, 10:09:29 pm
content: Quote from: tooki on February 21, 2017, 09:46:41 pmGood deal! I think you will like it.-bob

author: tooki
author_rank: Super Contributor
timestamp: February 22, 2017, 01:29:37 am
content: Quote from: bobaru on February 21, 2017, 10:09:29 pmI think I will!As for good deals... look in the Prema discussion above, MadTux scored the Datron 1271 for $50!! (Now with pix!)