Someone ask me to buy which dmm, Keysight 34465A or Keithley DMM6500 - Page 1
Forum section: electronics / testgear

author: hwj-d
author_rank: Frequent Contributor
timestamp: February 05, 2019, 08:01:42 am
content: Interesting question for the "hobbyist", i think.For this reason i wanted to put this question to the 6.5 digit lm399 based dmm's and my very subjective answer to it here also to the discussion:QuoteWhat do you think about that?

author: MrFox
author_rank: Contributor
timestamp: February 05, 2019, 06:43:39 pm
content: A few important features made me choose the 6500 as my workhorse dmm, each hobbyist have different needs but those are things to consider when making a checklist...Working with precision shunts, the 1 ohm range is very nice.For my high power leds projects, the 12V diode max is much more usable.The digitizer specs are far superior on the keithley, but admitedly only useful for special cases where scopes don't have the resolution/accuracy. For me it's a very narrow use case.Larger buffer is great for long runnning acquisition, testing something for 24h at 1 NPLC is possible.The switcher card expansion is compatible with the old model, easy to find on ebay.Naming things and entering values is so much better with a touchscreen.In canada at least, the keithley is a lot less expensive than the keysight.On the negative:For simple functions as a plain multimeter, direct buttons are probably more usable.10A is only in the back.Firmware is very young and needs improvements.Graphing crashed on me twice. Never happened again though.Buffer management is a little confusing because of the fragmentation, I suppose it will be solved in a later firmware.

author: hwj-d
author_rank: Frequent Contributor
timestamp: February 05, 2019, 08:03:34 pm
content: Thanks MrFox, for this additional points.

author: tautech
author_rank: Super Contributor
timestamp: February 05, 2019, 09:39:35 pm
content: Irrespective of brand/model, doesn't budget play a major factor in a decision ?And if it's high enough, newandwarranty vs 2nd hand ?Say if you spend 500 Euro on a 2nd hand unit and a new 6.5 digit bench DMM is 689 Euro........

author: hwj-d
author_rank: Frequent Contributor
timestamp: February 05, 2019, 11:37:50 pm
content: @tautechInteresting.On Topic: Keysight 34465AorKeithley DMM6500.Which one of them, new, do you have for 689€ ?

author: nctnico
author_rank: Super Contributor
timestamp: February 06, 2019, 12:04:47 am
content: According to some Youtube videos the DMM6500 seems to have a touch screen. I have a 34461A which is related to the 34465A. When I bought the 34461A Tektronix only had older models but the DMM6500 looks mighty nice to operate so I'm not sure I would buy the 34461A again if I'd had to choose today.

author: DaJMasta
author_rank: Super Contributor
timestamp: February 06, 2019, 01:21:01 am
content: Quote from: nctnico on February 06, 2019, 12:04:47 amWould be interested to see it on video, but similar thoughts. Lots of extra memory and I think I do prefer the GUI/looks of the Keithley, and the programmability I've seen demonstrated looks very nice. While the firmware is younger, my guess is that it borrows a lot from their earlier 7.5 digit meters in the same GUI, if not almost everything, so my initial assumption would be that it feels pretty mature to use.

author: kj7e
author_rank: Frequent Contributor
timestamp: February 06, 2019, 01:42:11 am
content: I have both a 34465A and a DMM7510. The DMM6500 UI is very similar to the 7510, between the two I would pick the DMM6500 as its much more entertaining for the hobbyist. I believe the difference in performance between the two is minimal. That said, I love the 34465A, glad I have both.

author: TheSteve
author_rank: Unknown
timestamp: February 06, 2019, 01:47:34 am
content: If you want a super stable meter with excellent build quality that just works get the Keysight. If you don't mind the occasional crash then the DMM6500 sure seems to offer the most bang for the buck. It doesn't appear to have the highest build quality but the feature set and price sure make it appealing. I would think the firmware will become more stable overtime as well.edit - I think kj7e is right, for the hobbiest a DMM6500 would be more fun.

author: ebclr
author_rank: Super Contributor
timestamp: February 06, 2019, 02:51:19 am
content: "have the highest build qualityThe Keithley quality is state of art

author: Faith
author_rank: Unknown
timestamp: February 06, 2019, 04:11:23 am
content: Used to own the 34465A, played with the DMM6500 a little bit... the 34465A seems to reach stability a lot faster (even compared to the 34470A)... but I would buy the DMM6500 if I needed another bench DMM without doubt.Really like the scripting of the DMM6500/7510!~For hobby definitely 100% would recommend the DMM6500... much more fun to use haha. Even if the 34465A gives better readings (which isn't really by a lot), for hobby use it doesn't matter.Only annoying thing is 10A input at the back... but really that is what handheld DMM / clamp meter / etc is for so whatever.Anyway best is you just demo and try both and see which one you like to use best!Edit:Just a small note, 34465A now comes with DIG option standard (50,000rdgs/sec) on latest firmware and MEM (2m memory points) is frequently given out for free too.So it is now cheaper to own fully unlocked than it used to be, but still a very expensive DMM.Also another consideration is support in your country.Where I live Keysight support is super... but almost all companies under Danaher (Fluke, Tektronix, etc) have really super crap reputation for their support.So think about that too.

author: Inverted18650
author_rank: Frequent Contributor
timestamp: February 06, 2019, 04:38:44 am
content: I just bought a DMM7510 and its so much fun! Moreover, its such a versatile machine with deep bandwitdh and am amazing array of features. Someone recently told me, "its like a 7.5 digit digital oscilloscope and more" and they were BANG ON. Keithley DMM6500 is they way to go mate, that's even before we talk about KickStart and the added functionality it brings. You will go from "just a hobby guy" to being able to send accurate data with graphs of every characteristic you need to make it truly professional. Tempco, deviation, histograms, etc etc...it measures everything you need right out of the box (after an 1.5 hr warm up) expect inductance... its the only meter you will need on your benchliterally got here today*

author: nctnico
author_rank: Super Contributor
timestamp: February 06, 2019, 11:30:58 am
content: Quote from: ebclr on February 06, 2019, 02:51:19 amEuuhhh... Keithley is Tektronix and Tektronix is owned by Danaher. Nowadays Tektronix rebadges a lot of low end stuff.

author: MrFox
author_rank: Contributor
timestamp: February 06, 2019, 03:44:34 pm
content: Quote from: nctnico on February 06, 2019, 11:30:58 amBut the 6500 is not a rebadged low end stuff. It's clearly a derivative of their 7510 and SMUs.Whatever tek does OEM is usually obvious.

author: hwj-d
author_rank: Frequent Contributor
timestamp: February 06, 2019, 04:23:52 pm
content: The instrument does not deserve a bad reputation, nor does it actually deserve to badly measuring because of remedyable shortcomings.Edit: But frankly sayd, the 7510 is a completely different house in terms of measuring and technical construction.

author: kj7e
author_rank: Frequent Contributor
timestamp: February 06, 2019, 04:36:52 pm
content: Quote from: MrFox on February 06, 2019, 03:44:34 pmWhile the 6500 and 7510 share almost the same UI, the hardware is not in the same class. It's clear the DMM6500 hardware was built to a price point with the Keysight 3446a target in mind. The 6500 is very fine meter and I'm sure will endure for many years, but I also believe the Keysight equivalent has the edge in both hardware and firmware quality/stability. If I was in the market now, I would still pick the DMM6500 over the 34465a due to the more advanced UI while still having very comparable specifications.

author: dmm2018
author_rank: Contributor
timestamp: February 12, 2019, 06:23:08 pm
content: Keysight 34465A/34470A has higher uncertainty in low resistance measurement.For example:[1Ω measurement uncertainty]Keysight 34465A/34470A: ~0.4%DMM6500 uncertainty: ~0.03%[0.1Ω measurement uncertainty]Keysight 34465A/34470A: ~4%DMM6500 uncertainty: ~0.2%[0.01Ω measurement uncertainty]Keysight 34465A/34470A: ~40%DMM6500 uncertainty: ~2%[0.001Ω measurement uncertainty]Keysight 34465A/34470A: ~400%DMM6500 uncertainty: ~20%Quote from: Faith on February 06, 2019, 04:11:23 amAgree... Keysight support at where I live is very good... but the support (after sales) of those claim to be Tektronix distributor is not that good.

author: HighVoltage
author_rank: Super Contributor
timestamp: February 12, 2019, 06:41:35 pm
content: I have the 34465A, the 34470A the DMM7510 and since Christmas the DMM6500They are all really good meters.But, right now I prefer the Keithley DMM6500, since it is the only meter I have bought with spot on calibration for voltage and resistance.It even confirmed one of my Burster 200 mOhm calibration resistors to 0.20000x Ohm (Wow, what a surprise).This would not work on either Keysight or the DMM7510.But I still would keep all four of them!

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2019, 10:43:15 pm
content: IMHO you should use special meters to measure in milli-Ohm territory. A good LCR meter or low resistance meter would be more suitable.

author: dmm2018
author_rank: Contributor
timestamp: February 13, 2019, 05:29:23 am
content: At TESTEQUITY:Keysight 34465A >> USD1454Keithley DMM6500 >> USD1140Is the 1Ω range (test current = 10mA) circuit difficult to be implemented?

author: MikeP
author_rank: Regular Contributor
timestamp: February 15, 2019, 08:12:47 pm
content: Quote from: dmm2018 on February 12, 2019, 06:23:08 pmWhere did you get this information?

author: Mr. Scram
author_rank: Super Contributor
timestamp: February 15, 2019, 09:08:53 pm
content: Quote from: dmm2018 on February 13, 2019, 05:29:23 amThe prices make it a no brainer, unless you have requirements only the Keysight can fulfil.

author: MrFox
author_rank: Contributor
timestamp: February 15, 2019, 10:24:51 pm
content: Quote from: nctnico on February 12, 2019, 10:43:15 pmI really wanted one until I saw the prices.The bench LCR meters that are anywhere near the resolution and accuracy of the dmm6500 low resistance ranges seem to be very expensive.

author: Joel_l
author_rank: Frequent Contributor
timestamp: March 31, 2019, 05:17:56 pm
content: I was about to pull the trigger on a Keysight 34465A when I ran across this thread. It steered me to the DMM6500 instead. My initial investigation was driving me towards the Siglent SDM3065X and the 34465a. Specmanship wise, the DMM6500 just seemed to be a clear winner at a price point between the two. I've had it a few days now and am still getting familiar with its operation, but I'm pleased with the purchase. Lot more bang for the buck. I was looking at the 34465A with the memory and digitizer upgrade which would add $$$$$$.The only downside to me is what has been mentioned, 10A current only on the back.

author: HighVoltage
author_rank: Super Contributor
timestamp: March 31, 2019, 10:04:48 pm
content: In voltage mode, the DMM6500 is a reliable 6 1/2 digit meter and it stays stable without noticable drift.Here I was testing a very stable 10.000,040 V source.The calibration of my DMM6500 is about 20 uV off, which is about the same offset at my DMM7510.Otherwise it has proven to be very reliable so far.The pk/pk span is about 27 uV

author: HighVoltage
author_rank: Super Contributor
timestamp: March 31, 2019, 10:10:43 pm
content: At the same source, the DMM7510 shows a pk to pk of only 7 uVBut about the same offset of around 27 uVMy observation so far with the DMM7510 and DMM6500 is very good, except this calibration offset.

author: hwj-d
author_rank: Frequent Contributor
timestamp: April 01, 2019, 11:28:00 pm
content: Thank youHighVoltage. I'll take care of it. This comparison gives me hope without having the 7510. My DMM6500 shows an surprising similar result, without having my refs calibrated so far, which I still have to do.Far behind meanwhile my Keysight 34461A. Without ACAL it shows an amazingly high temperature drift compared to the DMM6500.

author: alex-sh
author_rank: Regular Contributor
timestamp: April 23, 2019, 10:35:04 am
content: Quote from: hwj-d on February 05, 2019, 08:01:42 amAbsolutely DMM6500 - this is what I bought several months ago.Do not get me wrong, 34465A is an excellent meter. However, purely from GUI perspective DMM6500 is much more refined.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 06, 2019, 06:15:30 pm
content: There has been some discussion about the feasibility of making simultaneous primary and secondary measurements with respect to relay switching and relay wear - but maybe there is a way around the relay issue....At about 14:30-15:40 this indicates by being flexible on the selection of a compatible range for the secondary measurement (and I guess by definition the range for the primary measurement too) the relay switching might not be needed for dual measurements.Have users found that it is generally practical to find a suitable same-range so you can record both measurements simultaneously without invoking relay switching?When you record two measurements at the same time can you then see/review both measurements (with trendlines or table views) at the same time using just the front panel display?On a related question, what's the longest I or V recording duration anyone has seen on the 6500? minutes, hours, days?Thanks, EF

author: JxR
author_rank: Unknown
timestamp: June 06, 2019, 06:20:13 pm
content: Quote from: Electro Fan on June 06, 2019, 06:15:30 pmYes, you need to set the current from Auto to 1A or 3A ranges. This will stop relay switching and was confirmed by Brad at Keithley, and tested personally by myself. The voltage can be left on Auto range also.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 06, 2019, 06:26:35 pm
content: Quote from: JxR on June 06, 2019, 06:20:13 pmThanks for the super fast reply! How about the 10A range? - can that also potentially also be aligned with the other measurement?For example, if you have a power supply that runs at 24V and anywhere from 400mA to 4A, if we aren't too picky about the axis label spans on the graph, would it be feasible to measure both without the relays to see the trends of both over time, or is the notion of compatible ranges more theoretical than practical? Thx again

author: JxR
author_rank: Unknown
timestamp: June 06, 2019, 06:37:07 pm
content: Quote from: Electro Fan on June 06, 2019, 06:26:35 pmThere is no relay switching using the rear panel 10A input, and with the current range set to 10A. I just tested @20V with a load from 100mA to 3A. No relay clicking occurred. That is the best test I can do on short notice given the ranges you gave. Basically my power supply is 2x channel 20V, but only can sink up to 3A. While I could source 6A @ 20V, I don't have anything I can sink the current to get 4A. Although given that I was on the 10A range on the DMM, I see no reason to assume that this behavior would change at 4A.

author: JxR
author_rank: Unknown
timestamp: June 06, 2019, 06:59:15 pm
content: Quote from: Electro Fan on June 06, 2019, 06:26:35 pmYou can only do graphs and trends on the primary measurement. What ever is set to the secondary measurement has no statistics available as far as I'm aware. You can of course swap between the primary and secondary measurements at any time, but whatever is set to secondary only gives you the numerical value at that moment in time.This behavior may be completely different if you had one of those scanner cards to use, but then you are certainly going to be using relays. You may need to dig into the manual, or see if Brad on the big DMM6500 forum post can answer your question.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 06, 2019, 07:07:27 pm
content: Quote from: JxR on June 06, 2019, 06:37:07 pmSo in general it seems not only feasible but practical to pick a range that should allow simultaneous V and I recordings with no relay switching. Cool(I think Keithley should make a video showing this for some plausible measurement values.)Only 3 questions left1. Can you see the V and I trendlines on the front panel display simultaneously?(Keithley should put this in the video too.)2. How long (minutes, hours, days) can you record V and I?(Keithley should explain this in more clear detail in the spec sheet.)3. How noisy really is the fan (how many dB at 1 meter distance?)(Keithley should publish this spec if they haven't already.)Thanks

author: JxR
author_rank: Unknown
timestamp: June 06, 2019, 07:21:59 pm
content: Quote from: Electro Fan on June 06, 2019, 07:07:27 pmNo, only the primary measurement has graphs and trends.Quote from: Electro Fan on June 06, 2019, 07:07:27 pmYou can't record both simultaneously. At least not without a scan card, and then you would be using relays.You could record indefinitely as far as I'm aware, but you might need to use KickStart, and set a sample rate that doesn't exceed the transfer rate over ethernet. For the internal buffers, it would just depend on your settings and buffer sizes. I expect you could make settings to record for days on the internal buffer only, but I have never tried it. You can set measurement delays, count, and sample rate. Just so you don't want a ridiculous sample rate you can probably stretch it out for a good long while.Quote from: Electro Fan on June 06, 2019, 07:07:27 pmI have no equipment to tell you this. I can hear it. It is a pretty faint background hum. It is low enough in volume that I could honestly forget its on, but loud enough to notice the difference when I turn it off. It certainly doesn't bother me, or is it at a frequency that is irritating to me. Anyways, I don't personally feel like the noise is a problem. Although, I should clarify that a good portion of my adult life was spent working out of massive server rooms. I'm pretty tolerant when it comes to background noises.

author: Brad O
author_rank: Regular Contributor
timestamp: June 06, 2019, 07:23:42 pm
content: Quote from: JxR on June 06, 2019, 06:59:15 pmYou can graph the secondary measurement. Secondary measurements are written to defbuffer2 (you must be on defbuffer1 to use secondary measurements) so you go to MENU > Graph > Data > Add defbuffer2 as a trace. The Statistics swipe screen will only show stats on the active buffer (so the primary measurement), but you can see some buffer stats for the secondary measurement on the graph screen by switching traces.Quote from: JxR on June 06, 2019, 06:37:07 pmCorrect, relay switching is dependent on the range selected, it doesn't care what the actual measurement is.Quote from: Electro Fan on June 06, 2019, 06:15:30 pmI've digitized at 1MS/s into a Continuous buffer for ~2 weeks. That's the longest I've done but I believe others have data-logged for longer, at least with integrated measurements, not sure about digitizing.Quote from: Electro Fan on June 06, 2019, 07:07:27 pmYes, the front panel swipe screen will show the graph you've configured on the graph screen, you don't have any ability to edit the graph from the swipe screen though.Quote from: Electro Fan on June 06, 2019, 06:15:30 pmYou're only limited by the size of your buffer and the speed of your measurements. With a continuous buffer, you can theoretically record forever but you can't keep all the data as it's overwritten. The KickStart software is a solution for very long term data-logging, writing a script to handle creating csv files automatically is another potential solution.Quote from: Electro Fan on June 06, 2019, 06:15:30 pmThis one I don't know, I don't have a dB-meter unfortunately. It's one of the quieter instruments onmybench, but other people seem to think it's louder than other products in its class. That's not really a spec we would publish because then we'd have to dB-meter all the instruments in an anechoic chamber.Quote from: Electro Fan on June 06, 2019, 06:15:30 pmThank you for the ideas on the videos! I will add them to my to-do list...

author: JxR
author_rank: Unknown
timestamp: June 06, 2019, 07:30:03 pm
content: Quote from: Brad O on June 06, 2019, 07:23:42 pmWow, that is awesome. I learn something new about the device every time you post it seems. Thanks Brad!

author: Electro Fan
author_rank: Super Contributor
timestamp: June 06, 2019, 11:49:34 pm
content: Quote from: Brad O on June 06, 2019, 07:23:42 pmBrad, thanks for all the info but I'm still not clear.... the answer to the first question sounds like the 6500 CANNOT simultaneously display V and I in one graph on the front panel display. The answer to the second question sounds like maybe you CAN display the V and I trend lines simultaneously.For the use case I have in mind I don't need to edit the graph, just see a graph showing both V and I over some time period of time. Is this possible or not? If it's not possible (which I'm guessing is the answer), I think it might be a good feature to add. It would probably require the ability of the firmware to label time units on the X axis while labeling V units on one side of the graph and I units on the other side of the graph. Thx

author: JxR
author_rank: Unknown
timestamp: June 07, 2019, 01:39:56 am
content: Quote from: Electro Fan on June 06, 2019, 11:49:34 pmOk, I did try this out. Both traces can be seen simultaneously. Although, I do not see a scale for both traces simultaneously. After you add both buffers to the data for the graph, you see both trend lines, but then you have to click which buffer scale shows up on the y-axis (along with its statistical data). It is literally a single button press to change the y-axis between the two while watching the trend lines display, but there does not appear to be a way to show both scales on separate sides of the y-axis.Of course since the data is there in both buffers, it would be simple enough to put a graph up in excel or some other program after retrieving the data. I agree that it would be ideal to have both scales on separate sides of the y-axis. Regardless it is pretty cool you can get the data from both measurements in the first place.I personally would like to see this change, and I would like to be able to perform a secondary measurement in KickStart for the DMM app. This functionality already exists in KickStart for the SMUs, so hopefully they will consider adding it.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 07, 2019, 02:24:06 am
content: You can see the two lines traveling along next to each other so you can see trends - that’s a pretty good start.If you could post an image from your test that would be cool.Below is a quote from hwj-d that describes my impression - the 7500/6500 is a new architecture and it might take a while to mature to meet all the likely use cases but it seems to be built on a very capable foundation. Plus, Keithley seems pretty open to hear input and participate in discussion with users. All good.Quote from: hwj-d on February 20, 2019, 01:23:15 pm

author: JxR
author_rank: Unknown
timestamp: June 07, 2019, 02:59:59 am
content: Ok, here you go.The test is as follows:Sweep voltage from 1-10V in 1V increments and 1s steps, then stopSweep current from 100mA-1A in 100mA increments every 0.1s (repeated)In the bottom left corner where you see the name of the buffer is where I click to change between the two scales on the y-axis. For the actual range of the scale on the y-axis this particular mode is called auto-independent. There are other range scales you can pick, however whatever scaling system you use is shared between both measurements. For instance I could turn auto-scaling off and set: minimum at 0V, and 1V increment. That would then make the current scale the same (0A, 1A increment). That would have obviously made the blue trace much smaller in scale.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 07, 2019, 04:42:37 am
content: Thanks for doing that and showing the results.Seems like the core idea - dual measurement trend lines over the same timeframe on one graph with no relay switching - is very doable. Might be nice if Keithley can provide some added user friendly control over axis increments/spans and (two sided) y axis labels but it looks like the 6500 is close as-is.

author: hwj-d
author_rank: Frequent Contributor
timestamp: June 07, 2019, 08:05:51 am
content: Quote from: JxR on June 07, 2019, 01:39:56 amYes, or use the dmm's script/API to develop an app inside, to use it like a watt-meter or whatever.

author: Electro Fan
author_rank: Super Contributor
timestamp: June 07, 2019, 03:50:12 pm
content: Seems like in addition to being a great DMM, with TSP and Lua, the 6500 is a gateway drug that puts hardware enthusiasts on the path to becoming software enthusiasts

author: tszaboo
author_rank: Super Contributor
timestamp: June 11, 2019, 07:42:13 am
content: We have a few 34465A and a DMM6500 in the office. Whenever I can measure something with the 34465A, I always choose that. UI is better, the package is smaller, I've been using it for years, trust it.The DMM6500... Well it can measure really fast. UI is clunky, illogical, it does BSOD sometimes. Readings are not always visible. It is HUGE. But it is also a lot cheaper, and the high sample rate is useful, when it works.TBH if I would spend my own money I would buy the Keithley.

author: Wintel
author_rank: Regular Contributor
timestamp: August 11, 2019, 10:12:08 pm
content: Does the DMM6500 can show one more digits, the 7.5th Digits in the STATISTICS screen like Keysight 34465A?In Keysight 34465A, when enable the MATH -> Statistics function, the screen can display one more digits (the 7.5th Digits) in Average, like Average: +10.000,123 V, does DMM6500 can get the 7.5th Digits in the STATISTICS screen ?

author: hwj-d
author_rank: Frequent Contributor
timestamp: August 11, 2019, 10:57:58 pm
content: Quote from: Wintel on August 11, 2019, 10:12:08 pmYes:(your example, on both instruments only if DCV >=10V and <11V)

author: Wintel
author_rank: Regular Contributor
timestamp: August 12, 2019, 12:18:09 am
content: Quote from: hwj-d on August 11, 2019, 10:57:58 pmThanks for your reply.Would you mind to do one more test? If DCV > 10V, does DMM6500 also can show the 7.5 digits like 34461A?Because I find some DMM6500 screen, if DCV >10, the Statistics -> Avg: is 6.5 digits only.

author: AG7CK
author_rank: Regular Contributor
timestamp: August 12, 2019, 03:43:40 am
content: Picture copied from post above:On my meter (latest firmware), the average changes from 9.999999 to 10.00000 volt when I let a voltage source drift upwards, and reverts from 10.xxxxx to 9.xxxxxx when the voltage passes 10.0 volt downwards. This is because the print format is 7 digits with variable floating point. This must result from the programmer not knowing the instrument's specifications and it's intended use. No instrument designer would present a 6.5 digit DMM without a 7.5 digit average for 10 volt DC.A clear sign of the programmer's total lack of knowledge or thinking, is the apparent resolution of Peak to Peak. Since one can assume that this number is a subtraction of Minimum from Maximum with a maximum resolution of 1 microvolt in this meter class' typical 20 bit or so ADC), it's apparent resolution in picovolts (4.884417 microvolt is 4,884,417 picovolt) is meaningless and looks embarrassing. Similar cases can be argued for all values presented.This screen needs reprogramming.

author: AG7CK
author_rank: Regular Contributor
timestamp: August 12, 2019, 04:10:25 am
content: Somone just sent me a message saying that a 6.5 digit DMM must have a 24 bit ADC. OK for me. I withdraw from any discussion. I guess I should have written "20 bit or more ADC".Anyway: For Maximum = Minimum in the picture above (both presented with 10 microvolt resolution), it seems that Peak to Peak should prima facie be 0. As in: 7.12409 - 7.12409 = 0. Hence, for Peak to Peak to be 4 or 5 microvolt, there must be a microvolt hidden somewhereThat's all I wanted to say.A nice read for bits, ENOBs, counts and resolution is:http://zone.ni.com/reference/en-XX/help/370384V-01/dmm/resolution_bits_digits/

author: Wintel
author_rank: Regular Contributor
timestamp: August 12, 2019, 08:29:01 am
content: Quote from: AG7CK on August 12, 2019, 03:43:40 amDoes DMM6500 have the same print format problem in the 1V and 100V range?

author: hwj-d
author_rank: Frequent Contributor
timestamp: August 12, 2019, 11:02:45 am
content: Quote from: AG7CK on August 12, 2019, 03:43:40 amThe DMM has some issues not only with his GUI yes. We are all waiting for the overdue Firmwareupdate. For this, I specally posted the first screenshot. Have you seen it?For my part, I can handle this innovative DMM in such a way that I get the information I need. My Keysight 34461A has other similar drawbacks in its GUI also, its capabilities, and its very own high temperature drift, which makes me prefer the much more flexible DMM6500 all the time.

author: Electro Fan
author_rank: Super Contributor
timestamp: August 20, 2019, 09:28:52 pm
content: There was some discussion awhile back about doing V and I measurements at the same time; seems like this is the basic idea....https://buzz.tek.com/c/tektronix-smu-bundle?x=m5R2qC&mkt_tok=eyJpIjoiTUdVNE16WXdPVGhsTVdRMyIsInQiOiJmaWptVU9hcmdnM2llTnU1UjVRcityWWxkWXhobXNlYmhuaVlmaGlGZUZpMlQ4K3ZocjdBak5TNkJCN2FcLzhzVDladnFIbkE0dm1qelVaTTNEUjZPY0pJZFljMHkremdNQTBuZWhoR1hSdjJkalwveTN5cmxwXC9jN1FSUDNNR1ZBMSJ9

author: Electro Fan
author_rank: Super Contributor
timestamp: October 05, 2019, 10:50:06 pm
content: Still kicking around the idea of a bench DMM. Siglent 3055 looks pretty attractive in terms of price but when you start looking at all the specs (measurement ranges, etc) and all the features/functions the Keithley 6500 is also very attractive.Question on 4 wire measurements:.... what are the chances that in order to fully utilize the low Ohms measurement of the 6500 you really need something like this?https://www.newark.com/keithley/5806/lead-set-2-clip-test-leads-banana/dp/59T8473?MER=bn_level5_5NP_EngagementRecSingleItem_3$355 (vs. eBay version?) kind of ups overall price for the $1140 for the 6500What are the chances that these would somehow support the accuracy of the 6500?https://www.ebay.com/itm/2-4-Wire-Kelvin-Test-Clips-with-4mm-connectors-for-the-AE20218-Milliohm-Meter/264294515613?hash=item3d892e439d:g:HDAAAOSwvXZcvj1PMaybe the 5806 earns $355 for industrial strength and the eBay Kelvin clips would provide good measurements if handled gently....?

author: Electro Fan
author_rank: Super Contributor
timestamp: October 06, 2019, 12:00:08 am
content: Or maybe these?http://www.testequipmentdepot.com/bk-precision/accessories/test-leads-probes-adapters-clips/kelvin-clip-probes-with-four-banana-plugs-tldk1.htmhttp://www.farnell.com/datasheets/2721855.pdf?_ga=2.58480426.1872119853.1570314999-121656159.1570314999

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 06, 2019, 12:35:19 am
content: The beauty of four wire measurements is that you take the resistance of the cabling out of the equation. What remains are more subtle effects like tempco.

author: Electro Fan
author_rank: Super Contributor
timestamp: October 06, 2019, 02:32:57 am
content: Quote from: Mr. Scram on October 06, 2019, 12:35:19 amRoger that but does that mean the ability to deal with tempco accounts for the difference between $350 Kelvin clip leads and $50 Kelvin clip leads? What measurement differences would you expect to see when using the 6500 with the $350 leads vs the $50 or $25 leads? Thx

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 06, 2019, 03:18:55 am
content: Quote from: Electro Fan on October 06, 2019, 02:32:57 amI would honestly not expect to see much if any difference. The DMM6500 is an awesome DMM but 6.5 digits is not quite metrology grade yet. What you're looking at is likely some difference in build quality but mostly a brand premium. I'd go with the Extech or BK one as those are companies with something to lose if they screw up too badly.

author: tautech
author_rank: Super Contributor
timestamp: October 06, 2019, 05:10:33 am
content: Quote from: Mr. Scram on October 06, 2019, 12:35:19 amSo does Rel that any good DMM has, that's the whole purpose of it.Quote from: Electro Fan on October 06, 2019, 02:32:57 amWhat matters more is measurement repeatability, Tempco can be accounted for by refreshing the Rel setting periodically.

author: sergioag
author_rank: Unknown
timestamp: October 23, 2019, 05:40:46 am
content: I just pulled the trigger on a DMM6500. Had a 34461A, loved it. But it died within warranty. Seller was no longer selling Keysight equipment and referred to their supplier, who also was no longer selling and referred to another supplier, who never answered. Contacted a local representative and they absolutely refused to service it under warranty. They estimated that a board change would cost me about $1200, so I passed. No more Keysight for me, hence I'm trying Keithley this time. I don't expect any support, but as long as the multimeter works I'm happy.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 11, 2019, 11:45:27 pm
content: Quote from: sergioag on October 23, 2019, 05:40:46 amAny thoughts on the DMM6500 after having used it for awhile?

author: sergioag
author_rank: Unknown
timestamp: November 12, 2019, 03:38:52 am
content: Quote from: Electro Fan on November 11, 2019, 11:45:27 pmYes, a few. But it's been too little time to fully use it. But in summary:- No blue screens, reboots, or other problems.- Measure rate is really fast.- The UI is ok, but I still prefer hardware buttons. On the other hand, I can't think of a way of designing hardware buttons for such a broad range of functionality without making it really complex or making the instrument bigger. Guess this was a factor when designing the instrument.- Accuracy in DCV is about what I expected, as crosschecked with my various references (AD584L, LT1021BCN8-5, LTZ1000ACH).- Haven't been able to explore too much the graphing capabilities, but the touchscreen really excels on this.- Haven't tried programming yet.- Haven't tried Ethernet or USB connectivity.- Yes, it does feel like a huge upgrade compared to my dead 34461A.Hope this helps a bit.

author: MathWizard
author_rank: Super Contributor
timestamp: July 11, 2020, 10:29:10 pm
content: Quote from: Joel_l on March 31, 2019, 05:17:56 pmHmm so for me the 34465A and DMM6500 are pretty similar, and I was afraid of the touchscreen getting dirty all the time. But the Keysights don't even have dual display, thats not good.But yeah the DMM6500 is priced more like the 34461A, and with better Amps/Ohms.So what's all the extra feautures tho over the Keysight's ? Aren't they loaded with features ? So what all else does the Keithley do ?It sound like the DMM6500 can better act as multiple DMMs (so since I won't have many, I better consider that too)Keeping under 2000CAD means I could get 1 a lot faster.How do people find the screens hold up ? Both for dirt, and for if stuff like this breaks, if you don't have a warrenty, how expensive is it too actually fix these , if parts are even retail ?

author: ercapoccia
author_rank: Regular Contributor
timestamp: July 29, 2020, 04:43:36 pm
content: I was about to order a second Brymen BM869S for €175 just to have a second meter on the bench and i love my 869 and i saw that the DMM6500 is on sale for €855+vat from Welectron, it may be even cheaper if i ask for a discount and if i pay with bank transfer.I need just a stable meter for some non critical precision measurement, i won't send it for calibration, i just want a meter i can trust for 10 years or so.Any 6 1/2 counts meter would be an overkill, 5 and 1/2 is more than enough for my needs but if the better class meter is more trustworthy i'll be happy to pay the extra price.The 34465A is a very nice meter but is 30/40% more expensive than the DMM6500 here in EU, the 34461a is just a little more expensive.Would you guys get the Keithley over the Agilent 34461a? I have read that the DMM6500 has some software problem.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 30, 2020, 06:54:29 am
content: All three of them (DMM6500, 34461A, 34465A) are really good bench meters. I have all three and like them all a lot. The 34461A is now my standard bench DMM and it works extremely well and is stable. And the many buttons get you to the desired measurement right away.But the larger screen and the "touch" is something special with the DMM6500, once you are used to the interface.The software has been improved slowly but steadily. My DMM6500 has not crashed anymore.Maybe you get a loaner unit of each and test them out for your needs.It more or less comes down to a personal flavor.

author: ercapoccia
author_rank: Regular Contributor
timestamp: August 04, 2020, 04:10:31 pm
content: I've been reading about those meters. The KS 34465A (€1300) seems the one with the best overall review but it is way out of my budget and my needs, it is almost 50% more expensive than the DMM6500(€860). The most popular seems the KS 34461A (€980).There are not many post about the Keithley DMM seems that most people prefer the Agilent/Keysight alternative.Is there a particular reason? Compatibility with the 34401?

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 04, 2020, 05:02:07 pm
content: Quote from: ercapoccia on August 04, 2020, 04:10:31 pmThere's an extensive thread about the DMM6500 with hundreds of posts. It's a ridiculously capable and useful machine. The touch screen and processing power and what it allows for really does make everything else feel outdated. What I don't like are things unrelated to the functionality of the machine, specifically fan noise and transformer hum. The DMM6500 has 34401A compatibility so that shouldn't be an issue.https://www.eevblog.com/forum/testgear/new-keithley-dmm6500/

author: analogRF
author_rank: Super Contributor
timestamp: August 04, 2020, 05:47:51 pm
content: Quote from: ercapoccia on August 04, 2020, 04:10:31 pmKeysight eBay store very often sells used but excellent 34465A for LESS than $1080 and free shipping anywhere.I have never bought one and I am still comfortable with my trusty 34401A but 34465A can be had a lot cheaper than 1300 Euro

author: ercapoccia
author_rank: Regular Contributor
timestamp: August 04, 2020, 06:07:04 pm
content: Quote from: analogRF on August 04, 2020, 05:47:51 pmThank you for your feedback, i'll check it out. I was comparing price for brand new unit.Quote from: Mr. Scram on August 04, 2020, 05:02:07 pmThank you, i've read the whole thread. I meant there are fewer threads compared with the KS alternative. I watch many youtube videos about electronics and it's hard to see a Keithley, almost all the creators have KS/Agilent 3446x DMMI really like the DMM6500 and for the price is very tempting.

author: mawyatt
author_rank: Super Contributor
timestamp: August 04, 2020, 06:31:12 pm
content: We have a couple old 34401As, the oldest is an HP and over 30 years old, the other an Agilent is over 20 years old. Both acquired from eBay, and both still perform quite well (amazingly accurate considering their age and last cal decades ago!)! I can see why these instruments became the benchmark for 6 1/2 digit DVMs.Because of these 34401A instruments we just purchased the Keysight 34465A figuring this has some of the DNA of the older 34401As. The 34465A is indeed the younger more capable brother of the 34401A, everything about this instrument is so well done and thought out.Can't comment on the other instruments, but the 34465A is so nice and easy to use, no need for a user manual either!!Best,

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 04, 2020, 08:47:21 pm
content: Quote from: ercapoccia on August 04, 2020, 06:07:04 pmThe DMM6500 is a much newer device so time has been on the side of the Keysights in regards to visibility. The Keysights also used to be pretty much the only choice if you were after a graphical DMM, especially if a decent brand was required. If you pay attention you can see the DMM6500 and its many cousins in a surprising amount of videos though. The coherent ecosystem Keithley is building is something I much appreciate. I feel the DMM6500 is probably a bit more modern but I don't think there really is a bad choice to be made either way.

author: phs
author_rank: Contributor
timestamp: August 04, 2020, 11:27:20 pm
content: You might want to also compare the cost of calibration and repair, and where you would need to have that done, for each brand/model you're considering -- just in case...

author: JimKnopf
author_rank: Frequent Contributor
timestamp: September 08, 2020, 09:52:04 am
content: Hello,i'm an unhappy owner of an UT-8803e DMM which is a very inaccurate device. I bought it early this year and it feels like a pain every time i use it. I can't trust any measurement. So i'm looking for a proper Bench DMM with higher accuracy. I have also mobile DMM like Brymen BM239+. But i want one on the Bench permanently.I often use diode mode and continuity tester. The UT-8803e has a slow beeper and diode mode works only down to 16 ohm. All values below 16 Ohm it show me as an Err which means it's a short. My mobile DMM's work down to 4 ohm's in diode mode. What about the Keithley DMM6500? What is the lowest ohm value it shows before it indicates a short circuit? What about the continuity speed?

author: Howardlong
author_rank: Super Contributor
timestamp: September 18, 2020, 01:25:45 pm
content: Two recent additions to the lab, after some years with a 34401A, have been both a 34465A and a DMM6500.I have to say, of the two, I do prefer the DMM6500, predominantly because of the digitiser function... a function I never knew I needed. The touch screen UI of the digitiser on the DMM6500 lends itself far better to exploring the graphs compared to the 34465A, although overall the UI on the DMM6500 takes a bit more patience to get used to. For a start, the graphs are significantly larger on the DMM6500 display, and the screen resolution is much better (5" 800x480 vs 4.3" 480x272). I'd prefer it if the DMM6500 graph axes labelled themselves a bit better, using appropriately rounded values. I think the DMM6500 UI could still be improved upon: the UI thing does seem to be common theme on modern UIs at Tek/Keithley, they sometimes seem to have been designed and cobbled together by a committee, with little in the way of end user input (pun not intended).In simple continuous measurement mode, I do prefer the display on the Keysight, it's a lovely clear display. The touch screen on the DMM6500 inevitably does attract finger marks of course.The DMM6500 boots about twice as fast as the 34465A, but neither are anywhere near as fast as the 34401A, so the 34401A remains on the bench as a result!So yes, if I were to select one of the two it'd be the DMM6500. Better still, order both.

author: Howardlong
author_rank: Super Contributor
timestamp: September 18, 2020, 01:56:18 pm
content: Quote from: JimKnopf on September 08, 2020, 09:52:04 amNot sure what is meant by specifying resistance in diode mode, diodes are very non-linear. On the DMM6500 you can set the diode test current to 10uA, 100uA, 1mA or 10mA. Default is 1mA. You can also set the minimum and maximum voltage window: between 300mV and 800mV is default. 10V is the maximum.Continuity speed is OK but I don't think it's quite as good as the 34401A or the 34465A. On the DMM6500 you can set the trigger continuity to anywhere between 100m ohm to 1K ohm.The beeper tone (for continuity or diode mode) of the DMM6500 sounds like a buzzer rather than a beep: I much prefer the simple beep of the HP/Keysights.

author: JimKnopf
author_rank: Frequent Contributor
timestamp: September 18, 2020, 07:07:58 pm
content: Quote from: Howardlong on September 18, 2020, 01:56:18 pmThanks for the reply even it's not my thread. In the meantime I bought a DMM6500. An amazing device. I love it. Diode mode works perfectly down to the milliohm range. The beeper takes some getting used to but it is fast enough. A great device.

author: Electro Fan
author_rank: Super Contributor
timestamp: September 19, 2020, 01:37:50 am
content: Quote from: Howardlong on September 18, 2020, 01:25:45 pmThis is notable for at least two reasons:1) "I have to say, of the two, I do prefer the DMM6500": this is a significant endorsement for the 6500 coming from Howard.2) "I have to say, of the two, I do prefer the DMM6500, predominantly because of the digitiser function...a function I never knew I needed.": This indicates that even someone as experienced and analytically disciplined as Howard could potentially catch a case of TEA syndrome.Congrats on the 6500 - Enjoy!!

author: Howardlong
author_rank: Super Contributor
timestamp: September 19, 2020, 07:23:28 am
content: Quote from: Electro Fan on September 19, 2020, 01:37:50 amThere’s this really sweet bit of functionality on the DMM6500 where, despite the limited resolution and noise on the digitiser, you can super quickly and conveniently use touch screen cursors to average out thousands of samples to obtain better resolution. This is so incredibly useful for microcontroller applications that jump in and out of low power states.

author: Electro Fan
author_rank: Super Contributor
timestamp: September 19, 2020, 04:32:32 pm
content: Quote from: Howardlong on September 19, 2020, 07:23:28 amHow is that different than the trend chart with math showing the average? Maybe it’s because with the 6500 touch screen you can specify a subset of the samples to average rather just seeing the average of the entire set?Or maybe touch and drag cursors are more user friendly than using the hard button cursor controls on the Agilent?ThxEdit: I think I can answer my own question... I’m not in front of the 34465A but I think the cursors are only available on on the histogram and not the trend chart, so with the 34465A you can only use the cursors to designate bins, not selected samples. Might be a feature for Keysight to add but it seems like it’s headed toward a Blackberry buttons vs full touch Apple interface and we know how that worked out. I still wish I had the tactile feel of the Blackberry for high speed keyboarding but that’s generally not relevant on test equipment. I think the 6500 interface and approach to software is likely to influence Keysight’s architectural direction. I am very happy with the 34465A but I fully get why users might prefer the 6500. You are in the enviable position to have both (kind of like with Rigol and Siglent too), and between your AB test beds and your deluxe testing and insightful impressions it’s always great reading your posts.

author: Howardlong
author_rank: Super Contributor
timestamp: September 19, 2020, 05:06:04 pm
content: Quote from: Electro Fan on September 19, 2020, 04:32:32 pmBoth, but mostly that you can so easily choose subsets of samples post capture. If all I wanted was to measure a static value, I probably wouldn't be using an averaged digitiser result. The downside is that for very current values, averaging isn't accurate, there's significant offset.

author: felixsys
author_rank: Contributor
timestamp: December 24, 2021, 09:45:06 pm
content: If you are in Europe, go for Keysight. Better service, better guarantee.They are incredibly slow to respond and will always find excuses to avoid repairsYou will just be wasting your time with them.After some bad experiences with Tektronix .. I bought the DMM6500.1- The user interface is bad.2- The buzzing sound of the transformer will make you sick.3- Even in standby mode, the device consumes a lot of energy.

author: Hydron
author_rank: Super Contributor
timestamp: December 25, 2021, 11:44:47 am
content: Have you not followed the latest Keysight drama? If you're not buying for a business they're basically off limits in Europe.RE the DMM6500, the transformer thing is hit and miss, new ones are apparently much better as they made a change to the design.I got an ex demo unit which was older and made a lot of noise, they didn't hesitate to swap it (and then run the unit through cal) for free, though it was pretty slow (mainly due to shipping and customs, thanks Brexit!). New transformer completely solved the noise issue, though I wish they'd avoided it in the first place with a more conservative design.The standby use is annoying - I gotta admit that I'm tempted to try and do something to fix it.For doing a quick measurement the UI is a bit slower than using a pure button driven unit like the old VFD meters, but it's not too bad, and the flexible graphing etc is fantastic when you need it. Fair compromise in my opinion, and the meter was a lot cheaper than a new LCD Keysight (with slower boot time) would have been too.

author: HighVoltage
author_rank: Super Contributor
timestamp: December 28, 2021, 09:21:40 am
content: I still like both instruments a lot !The Keysight 34465A is a very good instrument, the ACAL function works well and the usability with all the buttons is just perfect.However, with the changes at Keysight for private people, it might not be a good idea to buy one.My Keithley DMM6500 has absolutely no hum at all.So, maybe when you get one with hum, just exchange it under warranty until you get one that is OK.