looking for decent multimeters - Page 1
Forum section: electronics / general

author: M. András
author_rank: Super Contributor
timestamp: November 23, 2011, 05:01:35 pm
content: hi, I'm looking for a multimeter for myself, home and for future possible work usage by myself at homethe benchtop what i was looking at are these:fluke 8808a, 8845/46aagilent 34405a, 34401aany recommendation on keithley ones and others whit decent quality and can be expected to serve a lifetime? pricetag up to the fluke 8846ahandheld:fluke 289, or the agilent's top oneif you own any of these what i listed i would be happy to read your opinion and experience about these performance, issues etc. and I'm also intrested in that if any of these holds the accuracy more than 1 year without calibration

author: Unknown
author_rank: Unknown
timestamp: November 23, 2011, 07:33:56 pm
content: Keithley 2000 is quite good and has specs very similar to the Agilent 34401A.Any high quality meter is likely to be accurate for a long time, especially after some time (drift tends to decrease with time). A Fluke 8846A has a much higher 1 year accuracy (24ppm at 10V range) than a Fluke 8808A (150ppm), so you can also expect the accuracy after two years to be much better. It's fairly rare to see 2 year accuracy specified, the Agilent 3458A is one of the few current ones that comes to mind. If you want guaranteed specs, observe the recommended calibration intervals. If it's not that important, it's fairly safe that a good quality meter won't be far of its 1 year specs as long as it doesn't get damaged or modified. It's not uncommon to find old meters by the likes of HP that have not been calibrated for many years that are still in spec. Of course these have the advantage that drift usually stabilizes with age.

author: grenert
author_rank: Frequent Contributor
timestamp: November 23, 2011, 10:52:27 pm
content: I've had the older Fluke 8840A, which was the precursor to the 45, which was the precursor to the 8808A. It was a real beast, mechanically. Beautifully made. I noticed the 8808A is made in China now, so I'm not sure the build quality would be the same. The 8846A is made in USA still.I have the 289 "handheld" meter. It is a great meter, but it will probably not leave your benchtop because it is HUGE and HEAVY. If that is OK, then I think you would like it. Mine has stayed in spec (as far as I can tell) for a couple of years without calibration. I think the best feature is event (changes in the reading, rather than recording at timed intervals) logging and being able to look at the result on the meter. No need to mess with a PC. However, note that you can't view a live graph of the data as its being logged. One other drawback besides the size is the high resolution display. I find a standard segmented LCD easier to read (and VFD even easier). That said, with all of the features available on the 289, the hi-res screen allows for menu selection which is very intuitive. Fluke leads (made by Pomona) are top quality. Fluke charges an arm and a leg for their PC Flukeview Forms software and USB cable, so if you're interested in getting that, I would buy the package with the meter and the cable/software included.If you are referring to the U1253A/B OLED meter as Agilent's top one, I don't have that meter but I do have the non-OLED version (U1252A) which is otherwise essentially the same. The user interface with the small, strangely placed buttons is weird to me, compared to Fluke's layout. I think the fast update speed of the display is supposed to be a feature, but I find the rapidly-changing numbers more of a distraction. It seems to be very accurate, but I haven't had mine long enough to say anything about long-term stability. The test leads/clips that it comes with are decent quality, but are not in the same league as Pomona. Agilent gives their PC software for the meter away free. I assume you've seen Dave's video review of this meter.Regarding the Agilent bench meters, I have no firsthand experience with any of them, but I have been looking at them, too. If you are going to spend the money for a 34401A, the 34410A is not much more money for a much more modern meter. It has USB and a dual display, as well as advanced logging features. It also has capacitance and temperature, which the 01A doesn't have. I don't see a good reason to get the 34401A unless you need to be consistent with other equipment you already have.

author: EEVblog
author_rank: Unknown
timestamp: November 24, 2011, 12:15:31 am
content: The (rebadged I think) Keithley bench meter has some very bad reports on various forums, beware.Dave.

author: robrenz
author_rank: Super Contributor
timestamp: November 24, 2011, 03:51:51 am
content: I looked at all the meters you listed before I bought a new 8846A. Formypurposes ofbench workonly (not automated system measurement) the 8846A has the most bang for the buck. It has wider ranges on many items and more unique features and has USB connectivity. There is no comparison between the Fluke and agilent displays. The Fluke display is much more readable and informative and the trend plot feature is really useful. I really like the meter it is even better than what I expected from reading the manual. The operation of the meter is much more intuitive than I expected.Just my opinion for what its worth, I am sure you will get others.

author: Unknown
author_rank: Unknown
timestamp: November 24, 2011, 09:25:24 pm
content: Quote from: EEVblog on November 24, 2011, 12:15:31 amYou're confusing the Keithley 2000 series with the Keithley 2100. The latter was a rebadged (Array?) design with a fair number of firmware issues, the 2000 series was introduced before the 2100 and I haven't seen any negative reports, please post a link if you have. This is why I specifically mentioned the model 2000. The 2001, 2002 and 2010 are also nice, but much more expensive.I think the main point in favor of the Agilent 34401A is that it has been the industry standard 6.5 digit bench meter for ages, while the Agilent 34410A and the Fluke 8846A are recent designs. This is why the Fluke 8846A can emulate the Agilent 34401A remote protocol. In the case of Fluke, they re-entered the market after they were out of this market segment for ten years or so. Nope, the Fluke 45 or rebadging Agilent equipment with a single resistor changed doesn't count. Another point in favor of the 34401A is that the service manual contains a complete schematic, something which is not the case for newer designs as far as I know. Agilent is pushing quite hard to replace the 34401A by the 34410/11A, so my guess is that the only reason why they still produce is because it's part of tons of procedures, and companies may be hesitant to rewrite/recertify those procedures and retrain staff.The only substantial negative I've heard about the Fluke 8845/8846A is a complaint about the split banana jacks not being very durable. One spec that Fluke doesn't do very good on is the reading rate. Max. 1000/second at 4.5 digits. This matches the old Agilent 34401A, is less than the 2000/second by the Keithley 2000 and is much less than the 10,000/s at 5.5 digit by the Agilent 34410A. This spec is mainly relevant for sampling or system use. Or characterizing parts, where you may have to cycle through all 2ncodes of a DAC. The Fluke 8846A is also more expensive than the Agilent 34401A, 34410A or Keithley 2000.I'm not trying to argue in favor or against any of these meters, just trying to give some more details.

author: M. András
author_rank: Super Contributor
timestamp: November 25, 2011, 04:13:17 pm
content: split banana jacks are used mainly for their special 2 lead 4wire resistance probe? but it will last for years if you dont plug/unplug them 30 times a day i guess (if not my choice would be that i make a very short extension cord with high quality banana plug/wire socket and wire, not so nice but it would be still better then that 750usd repair cost what i read here somewhere)i was checking farnell's prices when i made this list, unfortunately the only distributor in the country for keithley, is strictly sells only to companies.anyway so from keithley the 2000 series would be good choice too.that 8 hours battery life on the 1253 series is a joke, if it would be the only meter what i have and i only use it on the bench thats damn sure i would wire it to some lithium cells or a power supply, i will have time to think and talk about them to know more from each of these instruments before i will have the money for it.(i hope any of the handheld ones will be bought in 2-3 months)anyone have any information what are the changes between the 289 and the 289 eur model? the 289 eur is cheaper but internally whats changed? if anyone have an info from this

author: grenert
author_rank: Frequent Contributor
timestamp: November 25, 2011, 05:41:59 pm
content: One thing I've noticed looking at current bench meters is the usage of the secondary display. The Fluke 8808A and 8846A, and the Agilent 34405A appear to be able to show current and voltage simultaneously, while the higher-end Agilent 34410A cannot. That is really a shame, and I'm surprised that the lower end model has a feature lacking on a more expensive one. I was pretty well set on the 34410A, but now I am more seriously considering the Flukes.

author: robrenz
author_rank: Super Contributor
timestamp: November 25, 2011, 06:57:36 pm
content: 2nd display readings on the 8846AMAIN - SECONDARYDC volts - AC riding on the DCAC volts - DC offset of AC or Frequency of ACFrequency - PeriodPeriod - frequencyDC current - AC currentDC current - DC voltsAC current - DC current AC current is riding onTemperature - OhmsThe 2x4 wire kelvin probes are pretty nice. You can probe smd resistors right thru the carrier tape front or back. I asked fluke about them and they said the source and sense lines were kept separate as close to the probe tip as physicaly possible. The measurements agree very closely with my regular Kelvin clip leads.

author: grenert
author_rank: Frequent Contributor
timestamp: November 25, 2011, 07:37:57 pm
content: Thanks, Rob. Here is all that the 34410A can do:Primary Function - Second Display FunctionDC V, DC I, AC V, AC I - Peak–to–Peak valueFreq - AC VoltageTemp - Raw ResistanceIt's so limited that I would not really even consider the secondary display a feature.

author: robrenz
author_rank: Super Contributor
timestamp: November 25, 2011, 09:41:08 pm
content: I know I am sounding like a Fanboy but here are some of the things that made me choose the 8846A over the 34410 or 118846A 3341110 AMPS 3 AMPS1MHz 300KHz100 MILI FARAD 10 MICRO FARAD1000 AC VOLTS 750 AC VOLTS10 OHM 100 OHM8846A ONLYDiode test selectable 5V or 10V 1 mA or 100 microAContinuity selectable threshold 1 Ohm to 1000 Ohm 300 samples/sec with audibleMIN MAX AVG. SDEV # OF SAMPLES all displayed simultaneouslyManual offset inputMX+B of inputTrend Plot (Realy nice)Histogram displayDCV RATIO of 2 voltages with single common uses three leads.USB PORT extended memory stick stores up to 50000 readings + 10000 readings in internal memory.The 33411 measures up to 50000 readings per second, but at .001 power line cycle. the Fluke measures maximum 995 readings per second at .02 NPLC You have to decide if readings at .001 NPLC are accurate enough.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 25, 2011, 09:57:15 pm
content: Those Picometer (brand) looks well priced for what they do , give them a look.

author: ErikTheNorwegian
author_rank: Frequent Contributor
timestamp: November 25, 2011, 10:16:18 pm
content: I have a 8846A, and i must say, worth every penny/krone..I love this meter, and its just everything i can want i a bench meter.Only thing i don't like is that it starts in DC volt and flashes overload on and off, due to sensitivity of the DC mV when the measuring cables are connected...

author: Unknown
author_rank: Unknown
timestamp: November 25, 2011, 10:47:39 pm
content: Quote from: robrenz on November 25, 2011, 09:41:08 pmNot sure why you would compare the 8846 to the 34411, the 34411 completely blows the Fluke away in reading rate, and is equal to the 34410 in all other regards if I remember correctly.Quote from: robrenz on November 25, 2011, 09:41:08 pmYou can also set the null value on the Agilent 34401/10A. The DCV ratio and continuity are interesting omissions from the 34410A, since the 34401A does support them. The Fluke continuity spec was probably directly copied from the Agilent 34401A, which has exactly the same spec. The Keithley 2000 also has variable continuity threshold, multiple diode test ranges up to 10V, mX+b and null math functions. No fancy display modes or USB connectivity, however.Quote from: robrenz on November 25, 2011, 09:41:08 pmIt's hard to measure 50,000 reading per second at 0.02 NPLC, unless your mains frequency is 1 kHz or so. I believe the noise performance is quite good, but NMRR will off course be reduced. The Agilent 34410/11A will do 3000 readings per second at 0.02 NPLC, and various other speeds so you can trade off noise performance for speed. If this is an important spec for you, the Agilent 3441xA series is the only option (apart from the expensive Agilent 3458A) as far as I know.Note: the only reason why I only mention negatives of the 8846A is that you only mention positives, not because I think the Agilent 34410A is a better meter. Based on specs (I haven't used the Fluke 8846A) the Fluke 8846A appears superior in almost all aspects, but at a higher price.Quote from: ErikTheNorwegian on November 25, 2011, 10:16:18 pmThat's a common issue with bench meters. It doesn't take a lot of current to induce a few volts at > 10 Gohm input impedance.

author: robrenz
author_rank: Super Contributor
timestamp: November 25, 2011, 10:58:47 pm
content: To show Imighthave asmallbit of objectivity,The 33411 is slightly more accurate on frequency and capacitance, slightly less accurate on DC volts33411 has offset compensated ohms, very nice. You can accomplish the same thing with current reversal on the 8846A but a lot more work.8846A DC current burden voltage100 micro A <0.015 V1 mA 1<0.15 V10 mA <0.025 V100 mA <0.25 V400 mA <0.50 V1 A <0.05 V3 A <0.15 V10 A <0.5 V33411 DC current burden voltage100.0000 micro A <0.03 V1.000000 mA <0.3 V10.00000 mA <0.03 V100.0000 mA <0.3 V1.000000 A <0.80 V3.00000 A <2.0 V

author: robrenz
author_rank: Super Contributor
timestamp: November 25, 2011, 11:44:06 pm
content: Quote from: alm on November 25, 2011, 10:47:39 pmI think the reading rate is irrelevant for an actual Bench meter (not system use). If you need more than 995 readings per second the 33411 is the meter for you. but I cant decipher (I don't have the technical chops to figure it out) from the manual what the accuracy would be at that speed but I can see there is no normal mode rejection until you get to 1 NLPC and it looks like the accuracy really goes to pot at 50000.The reading rate and offset ohms are the only pluses I see for the 34411

author: Unknown
author_rank: Unknown
timestamp: November 26, 2011, 12:15:57 am
content: My point was: either reading rates are important to you and you get the Agilent 34411A, or they're not and you get the Agilent 34410A or one of the other options. I don't see an application where either the Fluke 8846A or the Agiletn 34411A would work, but not the Agilent 34410A.Of course the NMRR is zero at <1 NPLC, how do you reject periodic signals at less than a single period? Does any of the competitors do better? The solution is simple: don't have AC superimposed on your DC signals.Accuracy is quite good for 4.5 digits, about 0.01% of range extra uncertainty on most ranges. Better than the competition at similar reading rates, I think.

author: robrenz
author_rank: Super Contributor
timestamp: November 26, 2011, 04:18:33 am
content: Quote from: ErikTheNorwegian on November 25, 2011, 10:16:18 pmYou can store your favorite meter configuration as the power up configuration.Storing the Power-up ConfigurationTo store the Meter’s present configuration as a power-up configuration:1. Press (memory) button2. Press the STORE CONFIG softkey.3. Press the STORE POWER-UP softkey.The Meter configuration stored as a power-up configuration will be set whenever theMeter is powered on.You can also store 5 different configurations in internal memory and 99 configurations in external if you have a memory stick in the usb port

author: M. András
author_rank: Super Contributor
timestamp: November 26, 2011, 08:22:18 am
content: dual display sounds good and i listed it in my paper in front of methe 8846a looks like have the most of the function for the 2nd display, i didnt check it can store 10k readings in its memory or i missed it in the manual/spec sheet, and it makes a graph from those or it would display them as invidual readings?

author: robrenz
author_rank: Super Contributor
timestamp: November 26, 2011, 02:13:16 pm
content: Quote from: M. András on November 26, 2011, 08:22:18 amdetails of trend plothttp://www.myflukestore.com/crm_uploads/fluke_trendplot_-_data_logging_on_the_fluke_884x_with_trendplot_application_note.pdf

author: M. András
author_rank: Super Contributor
timestamp: November 26, 2011, 02:34:55 pm
content: Quote from: robrenz on November 26, 2011, 02:13:16 pmthank you

author: robrenz
author_rank: Super Contributor
timestamp: November 26, 2011, 03:18:03 pm
content: This also may be helpfullhttp://support.fluke.com/calibration-sales/Download/Asset/2547797_6203_ENG_B_W.PDF

author: M. András
author_rank: Super Contributor
timestamp: November 26, 2011, 06:38:47 pm
content: Quote from: robrenz on November 26, 2011, 03:18:03 pmi read this before but thanks

author: M. András
author_rank: Super Contributor
timestamp: November 26, 2011, 06:39:58 pm
content: anyone have any info from the fluke differences between the fluke 289 and the 289 eur model, what they changed etc.

author: IanB
author_rank: Super Contributor
timestamp: November 26, 2011, 06:58:22 pm
content: Quote from: M. András on November 26, 2011, 06:39:58 pmI think they changed the probes for new ones with more shielding over the metal parts to satisfy newer safety standards.Eventually the safety standards will require the probes to be entirely enclosed in plastic so that no metal parts are exposed at all. Then they will be completely safe

author: robrenz
author_rank: Super Contributor
timestamp: November 26, 2011, 10:45:03 pm
content: M. AndrásOne thing to be carefull about if you are buying a new meter especially since you are concerned about length of calibration.You want to be sure you will be getting a meter that has just been built and calibrated or at least freshly calibrated before it ships to you. When I was shopping for my 8846A in the US several places had them in stock but when I inquired about how long they had been on the shelf some had been there over a year. When I asked what about calibration the answer was it is as is, meaning the year specs were technically expired. I finally found tequipment.net where the meter is ordered from fluke and built to order obviously with fresh calibration (took 2 weeks). Also ask for quotes of their best prices. tequipment.net shows the retail price of US$1425.00 but they quoted me US$1296.00 If you buy one in the next 60 days they will include the 2x4wire Ohms test leadshttp://www.tequipment.net/Fluke8846ASpin.htmlI realize you are in Europe but the 8846A is built in the US so it would have to be shipped from the US to you anyway.

author: M. András
author_rank: Super Contributor
timestamp: November 27, 2011, 09:35:33 pm
content: there is an official distributor here in Hungary for the fluke where i asked for the 289 price and you can get that from stock, not many Hungarian company/distributor stocks damn expensive stuffs, they do calibration services too, but i dont know if they calibrate it when you buy the instrument or just gives the sealed box which was hell knows when was packed and shipped here from the US, i will ask them when i have time to go to their store, anyway the 289 is 1.5x more expensive here compared to digikey and tequipment prices, and of course 25% vat included in that 1.5x price (i love the direct 1:1 usd/eur conversionrather than the eur/usd to huf conversion) i dont know how much would be import these from the us cos i cant find any information at the local customs website, i didnt find a category for test equipment but i find 1 for nuclear reactors

author: M. András
author_rank: Super Contributor
timestamp: November 27, 2011, 10:07:06 pm
content: fluke 289 was 583 usd+ 25%vat about month ago at the distributor calculated at the current exchange rates, from farnell 662usd+25% vat and the eur model is 612usd+25%vat8846: 1554usd+25% vat, 8845: 1175usd+25% vat, 8808: 776usd+25% vat.agilent: 34401: 1016usd+25% vat, 34405: 720usd+25% vatjust for a quick price chart here in this countryinside the EUat the distributor they quote 58usd baseprice and 2usd for every measurment points(dunno what do they mean under this) for calibration for a multimeter

author: robrenz
author_rank: Super Contributor
timestamp: November 29, 2011, 01:40:14 am
content: Quote from: M. András on November 27, 2011, 10:07:06 pmmin, mid, and max for a range would be three measurment points x 5 ranges would be 15 points just for DCV then do that for again for ACV, DCI, ACI, Capacitance, frequency, resistance. You could ask for just max of each range to minimize cost.

author: M. András
author_rank: Super Contributor
timestamp: November 29, 2011, 09:47:54 am
content: Quote from: robrenz on November 29, 2011, 01:40:14 amthats a lotdo the fluke instruments comes with any sticker or cal certificate from the manufacturer when you buy them like the agilent ones? anyway i guess they do a full calibration anyway before they pack each of the instruments into their boxed

author: robrenz
author_rank: Super Contributor
timestamp: November 29, 2011, 01:13:09 pm
content: Quote from: M. András on November 29, 2011, 09:47:54 amPictures of:Cal stickerTamper proof stickerCalibration docsMisc. screen shots (on next post)Look at the Cal. data and see how much more accurate the meter is than the one year spec. You have read the Fluke calibration pdf and this Calibration shows how conservative that 2.6 standard deviations is. The screen looks better than the pictures, its hard to take pics of that display. The frequency pic. is blurred because of long shutter speed and digits bobbling. Notice the 10 nanoOhm internal resolution on the trend plot picture. Second display is showing in pics that use it.

author: robrenz
author_rank: Super Contributor
timestamp: November 29, 2011, 01:20:46 pm
content: Remaning pictures. Ok, I guess I am a 8846A Fanboy

author: grenert
author_rank: Frequent Contributor
timestamp: November 29, 2011, 02:36:40 pm
content: Quote from: robrenz on November 29, 2011, 01:13:09 pmWell, I'm sure it's a fine meter, but they really should have included the 24-hour spec with the data, which would have been a more appropriate comparison, since this was probably done right after calibration. Showing this "one hour" data point with the one year spec inappropriately exaggerates the accuracy. It's probably well within the 24 spec anyway, so they might as well make it easier to see (they publish 24-hr specs in the manual).Thanks for sharing the images

author: robrenz
author_rank: Super Contributor
timestamp: November 29, 2011, 02:49:44 pm
content: Quote from: M. András on November 27, 2011, 10:07:06 pmSo the Cal I showed has 125 measurement points so that would cost you 308usd. So if a dealer wants to sell one off the shelf you should either get a fresh Cal for free or a 308usd discount.

author: robrenz
author_rank: Super Contributor
timestamp: November 29, 2011, 03:25:37 pm
content: Quote from: grenert on November 29, 2011, 02:36:40 pmMy point here was more about how meter specs are a statisticaly based such that such that in flukes case they use 2.6 standard deviations such that 99% of meters will meet the specs as produced and after a year of additional aging/component drift (http://support.fluke.com/calibration-sales/Download/Asset/2547797_6203_ENG_B_W.PDF). That also means there is a very good chance your meter is way more accurate than the worst case Specs . Which is shown in this particular Cal (. I would Think the same thing would apply to Agilent or Keithley procucts.

author: Unknown
author_rank: Unknown
timestamp: November 29, 2011, 03:56:01 pm
content: I'm sure the other reputable manufacturers also apply guard banding to make sure their products meet their specs, but Fluke is the only one I've found to explicitly state that the specs are 99% confidence intervals. This is where the 2.6 * SD figure comes from, a two sided 99% confidence interval of a normal distribution is equal to the mean +/- 2.6 times the standard deviation.

author: M. András
author_rank: Super Contributor
timestamp: November 29, 2011, 09:22:44 pm
content: Quote from: robrenz on November 29, 2011, 02:49:44 pmi will ask the distributor when i will buy it, it would be good if they would calibrate it for free or even check the cal and if necessary they will calibrate the necessary ranges, i calculated the price for the 289 which is more likely to be bought first almost the half of the meter original price. i found another calibration labs whit fix prices for a full calibration for approx 200usd for multimeters

author: grenert
author_rank: Frequent Contributor
timestamp: December 03, 2011, 12:06:42 am
content: Quote from: robrenz on November 25, 2011, 11:44:06 pmI sent an email to Fluke asking if they had something like offset ohms. This was their reply:QuoteThat doesn't seem quite right to me, because you still have potential thermal EMF at the lead/resistor junction that won't be compensated for. Could someone tell me if my interpretation is correct?

author: Unknown
author_rank: Unknown
timestamp: December 03, 2011, 12:10:42 am
content: Maybe you should ask for offset compensated ohms? Or just how to compensate for offset voltages, like thermal EMF, in resistance measurements.

author: robrenz
author_rank: Super Contributor
timestamp: December 03, 2011, 02:06:55 am
content: Quote from: grenert on December 03, 2011, 12:06:42 amAs far as I know zeroing the meter does nothing for thermal EMF. You need to use current reversal on 4 wire kelvin connected setup. Take one reading, reverse the current take another reading and average them, that eliminates all thermal emf votages in the measurement. I made a setup for my 8846A to make the current reversal easy see reply 15 on this posthttps://www.eevblog.com/forum/index.php?topic=5460.msg71401#msg71401Offset Ohms takes a voltage measurement with no drive current, then takes a measurement with drive curent and take the difference between them.This keithley book is excellent and covers all this and moreThe whole book is excellent.http://www.keithley.com/knowledgecenter/knowledgecenter_pdf/LowLevMsHandbk_1.pdf

author: M. András
author_rank: Super Contributor
timestamp: December 03, 2011, 12:52:42 pm
content: i read somewhere here there are some autocalibrating bench meters, what are the entry level cost of these?

author: Unknown
author_rank: Unknown
timestamp: December 03, 2011, 01:13:10 pm
content: I believe autocal was a Datron brand name that stood for closed case calibration, ie. no need to adjust trimmers, only software constants. Many recent DMMs support this.You may also be referring to artifact calibration, calibration with just a voltage reference and a reference resistor. As far as I know the HP/Agilent 3458a is the only DMM that supports this, expect to pay a least a couple of thousand dollars on the used market, and more new.