Keysight 34460A/34461A/34465A/34470A Maximum Allowable Voltage change notice. - Page 1
Forum section: electronics / testgear

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 09:29:40 am
content: This issue wasreported by TheSteve in another threadbut it is not limited to the 34461A only and due to it's importance deserves a separate thread in my opinion.Here is the link to the notice.Here is the essence of it:QuoteCheersAlexP.S. It would be good to discuss possible implications. For example, the calibration procedure has to change too. If a failure occurs would it be a catastrophic one, taking half of your lab down?P.P.S. If you've bought a car specified for 120 mph maximum speed only to discover later that the car can actually break down if you exceed 80mphwhat would you do?P.P.P.S - Why I, as a Keysight customer with a registered 34465A meter, did not receive this update immediately on it's release on 17th of March, but learned about this critical issue here on the forum almost by chance?!

author: alm
author_rank: Super Contributor
timestamp: March 28, 2017, 10:04:34 am
content: Based on the very brief notice we can only speculate, but since they only mention the highest measurable voltage, and not the safety ratings, I would expect the worst case damage to be to destroy the meter. Not explode and take down half your lab.Since they talk about 'could, over the lifetime of the product, result in damage [...]', it could be something like a spark gap arcing over below 1000 V, gradually degrading it. If the meter is specified to measure DC voltages only up to 600 V, then I would argue the calibration procedure should not exceed that either.It would not surprise me if they supply a firmware update that shows overload for voltages over the new limits. Some Prema meters do the same when their maximum voltage is limited by an optional scanner card.The fact that they issue the change notice, and not a recall, suggests the issue is not limited to particular batches, and that they are not likely to offer modifications to existing units. Probably they think this change will not be critical for the majority of their customers. I would expect them to be working on a 34460B etc to fix this issue.

author: 0xfede
author_rank: Regular Contributor
timestamp: March 28, 2017, 10:26:26 am
content: I just finished the call with keysight and they confirmed it is an hardware issue.I'm waiting for an answer from keysight to my request of changing the multimeter.For now they leaked that on December 2017 there will be a new improved version of the 344XXX multimer line that should respect the advertised values.Let's see what happen.0xfede

author: Dr. Frank
author_rank: Super Contributor
timestamp: March 28, 2017, 10:34:38 am
content: That max. rating change is a severe problem, and KS should have informed all the customers about that, directly.The background is not clear at the moment, so 'damage' could mean everything, from slight component damages, until complete wreckage of the instrument.Also this term '.. over the lifetime of the instrument' is totally fuzzy.What happens if I use the instrument anyhow at 1000Vp, and a damage occurs, will KS repair / replace on their own cost?Will they fix this problem on already sold units?I started a request on the Keysight DMM forum, already.During the calibration process, 500VDC and 500VAC were proposed as standard values for the 1kV ranges.For DCV, 450V...1000V, and for ACV, 400V ... 750V would be accepted by the firmware.Frank

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 10:44:56 am
content: Quote from: Dr. Frank on March 28, 2017, 10:34:38 amThank you. It is 1000V DC and 750V AC (1kHz) on the performance verification routine (and on the calibration certificate) though.CheersAlex

author: HighVoltage
author_rank: Super Contributor
timestamp: March 28, 2017, 10:49:49 am
content: This is really impacting my lab work !I have three 34461A and one 34470A meter and I am using them all a lot in the range just under 1000 VDC, as I have done with the older 34401A meters as well in the past. The 34461A is suppose to be a full replacement for the 34401A.Limiting the meter now to 600 VDC will change a lot for me and for my customers who also have the 34461A meter in use now, integrated in to some test stands I have built for these customers. Now I need to notify my customers!And the 34401A, 34410A, 34411A meters have been taken out of production since 1/2017Which precision Keysight meter can I use now for 1000 VDC.This is really horrible news for me and I would like to know from Keysight:1. What is really the hardware problem?2. Why was I not notified of this?3. The solution to just amend the datasheet is not acceptable!

author: HighVoltage
author_rank: Super Contributor
timestamp: March 28, 2017, 11:02:26 am
content: Datatec, Germany has already updated their website with the new specificationsMeilhaus, Germany has not updated the specificationsSee screen shots below

author: Dr. Frank
author_rank: Super Contributor
timestamp: March 28, 2017, 11:03:34 am
content: If one looks into the 34411A schematics, which might be very close to the newer instruments, concerning the voltage input topology, the DCV and ACV path is identical up to one certain relay (K201 in the '411A).As both paths are affected in the same way, the culprit will be located between the input jacks and this relay.. and there are not so many components in between.As the components been used, seem to be the very same as in the 34411A, a layout error is most probable..On the pictures of the PCBs from the initial 3446xA thread, there are some internal PCB traces visible, which might be too narrow to other signal lines..So I suspect sparking inside the PCB layers, which can't be fixed other than a PCB redesign.Frank

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 11:03:58 am
content: Quote from: HighVoltage on March 28, 2017, 10:49:49 amExactly. I think that the only acceptable course of action from Keysight would be a full disclosure of the hardware failure issue in detail and a free hardware update. I understand that it would involve a lot of hassle (including, most likely, a re-certification of the meters) but anything less would be an attempt to get away with what is essentially a mis-sale .CheersAlex

author: Dr. Frank
author_rank: Super Contributor
timestamp: March 28, 2017, 11:11:33 am
content: Quote from: Alex Nikitin on March 28, 2017, 11:03:58 amIn addition, especially the occurring failure mode has to be explained in detail.Maybe the failure creates a mis-reading afterwards (instead of a real smoking damage), so it would not be possible for a high-voltage application to get aware of the problem.In other words, users as HighVoltage may have measured erroneously in the 1kV range for a long time, already.Frank

author: HighVoltage
author_rank: Super Contributor
timestamp: March 28, 2017, 11:13:07 am
content: Quote from: Dr. Frank on March 28, 2017, 11:03:34 amI totally agree.But if this is the case, then a PCB revision should be a the next step and not a change in specifications.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 11:49:17 am
content: Quote from: HighVoltage on March 28, 2017, 10:49:49 amIf the meters are used only on 1kV DCV range a possible solution would be to use an external calibrated divider 100:1 and 10V DCV range on the meters.Caddock divider arraysare not that expensive, very stable and usually available from stock.CheersAlex

author: HighVoltage
author_rank: Super Contributor
timestamp: March 28, 2017, 11:55:56 am
content: Quote from: Alex Nikitin on March 28, 2017, 11:49:17 amYes, there are solutions, of course.But my test stands are certified and have specific uncertainties. Adding a divider would change uncertainties and all documentations. What a nightmare ! And I don't think I will get paid for that by my customers.On the other hand, I just checked the calibration of one of my 34461A that has been used a lot just under 1000 V DC and it is right on spot. So may be Keysight is just too cautious about this issue. That is why it is so important that Keysight will tell us what is really going on in the hardware signal input path.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 28, 2017, 12:17:17 pm
content: My guess would be possible deterioration of HV resistors or protection devices over time.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 12:28:17 pm
content: Quote from: HighVoltage on March 28, 2017, 11:55:56 amYes, we need to know more, as it could be either (or both) a slow change in parameters (say, due to an increased leakage between tracks) or a complete failure with potentially serious implications for the meter and possibly the circuit connected.CheersAlex

author: EEVblog
author_rank: Unknown
timestamp: March 28, 2017, 12:28:55 pm
content: I suspect they have found (or had reported to them and investigated) that a high voltage component like a MOV or some such component used on the front end can deteriorate.I'm not buying it's a PCB layout issue, it's got to be component deterioration with repeated/sustained HV.And a company like Keysight can't just fix the problem in new units and that's that, as these are often used in critically specified systems. You can't just change things willy-nilly. So they have no choice but change the spec sheet for this model to reflect the worst case in all units sold and still in stock and production.Once they fix it they will come out with a B model or whatever like how they normally upgrade products like this.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 12:32:25 pm
content: Quote from: mikeselectricstuff on March 28, 2017, 12:17:17 pmThat kind of a failure can be fixed relatively easily by changing the components affected. So far I am inclined to go with Dr. Frank's guess on the board layout problem (and the board material can also deteriorate over time with a continuous application of a strong electric field).CheersAlex

author: wraper
author_rank: Unknown
timestamp: March 28, 2017, 01:07:54 pm
content: Quote from: Alex Nikitin on March 28, 2017, 12:32:25 pmI'd like to see how you "Relatively easy" recall every single meter ever sold, do a component level repair, recalibrate, and send back.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 01:21:54 pm
content: Quote from: wraper on March 28, 2017, 01:07:54 pmIt is still a lot easier and cheaper than to recall every single meter ever sold, replace the main pcb and then recalibrate and send back. There is no way around it, the meters were mis-sold. When a car manufacturer recalls 100000 cars to fix a problem for free, it does not surprise anybody. Here is essentially the same situation, s*it happens.CheersAlex

author: wraper
author_rank: Unknown
timestamp: March 28, 2017, 01:27:48 pm
content: Quote from: Alex Nikitin on March 28, 2017, 01:21:54 pmNot sure about it. With U127xA they choose to just send replacement meters instead, leaving you with 2 meters.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 01:41:01 pm
content: Quote from: wraper on March 28, 2017, 01:27:48 pmThe U127xA is most likely costs not that much to make, so a replacement could be the cheapest option, I am sure it is not an option with the top level bench meters.CheersAlex

author: Fgrir
author_rank: Regular Contributor
timestamp: March 28, 2017, 03:14:11 pm
content: I'd been thinking about buying a 34465A for my bench, but this spec change would be a deal-breaker for me so I'm glad I haven't pulled the trigger. I'll be curious to watch Keysight's response to the issue - anything less than a free replacement for affected users would seriously damage their credibility in my eyes.And you have to love targeted advertising...

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 03:41:22 pm
content: Quote from: Fgrir on March 28, 2017, 03:14:11 pmThe problem right now is that Keysight has nothing available even to replace these meters with(except, perhaps, 3458A but that would be a bit much to expect), so if you need to measure voltages over 600V DC and 440AC accurately, you have to look elsewhere or resort to some band-aids like an external voltage divider.CheersAlex

author: HighVoltage
author_rank: Super Contributor
timestamp: March 28, 2017, 03:57:22 pm
content: Quote from: Alex Nikitin on March 28, 2017, 03:41:22 pmMay be they will start production of the 34401A, 34410A, 34411A again.I am glad I still have some of the older models.In addition, the older models will now probably jump up in price on ebay around the world

author: Tom45
author_rank: Frequent Contributor
timestamp: March 28, 2017, 04:16:52 pm
content: This isn't much of a problem for me now that I know about it. In the rare cases I need to measure higher voltages I now know to use a different meter than my 34465A. It would have been nice if Keysight had notified me.But for those that need up to 1000 volts, Keysight had better get busy and take care of them.Edit: and thanks for making this a separate thread. I wouldn't have known about this otherwise.

author: nctnico
author_rank: Super Contributor
timestamp: March 28, 2017, 04:20:55 pm
content: Quote from: Alex Nikitin on March 28, 2017, 03:41:22 pmLet's wait and see what Keysight comes up with. It is not like the DMMs will catch fire when you apply 1000V. Maybe Daniel from Keysight can chime in?An alternative could be a DMM from Tektronix and it wouldn't surprise me if they have a compatible command set.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 28, 2017, 04:37:30 pm
content: Quote from: nctnico on March 28, 2017, 04:20:55 pmWe don't know that yet.CheersAlex

author: agdr
author_rank: Unknown
timestamp: March 28, 2017, 07:26:16 pm
content: Geezzz, this was a close call. I almost bought a 34470A two weeks ago, but got sidetracked when the R&S RTB scope deal came up. The other choice was the Fluke 8846A. I just took another look and sure enough the Fluke is (still!) rated at 1000V AC and DC. So along with all the other reasons, Keysight needs to get this fixed to stay up with the competition.

author: Cerebus
author_rank: Super Contributor
timestamp: March 29, 2017, 12:44:39 am
content: This is beginning to smell like the U127xA all over again.Their response to that was to change the published specifications and it was, in retrospect, clear that they had no plan to recall/replace these until they got given some stick on here. You'd think they would have learned something that time around and once they discovered this problem would have put acompleteplan in place and made complete, cogent and clear details available.The absence of those complete, clear and cogent details a second time around does immeasurable harm to the Keysight brand. When you make instruments that people the world around rely on youhaveto act proactively in a situation like this to maintain people's confidence and failure to do so yet again is inexcusable. If a couple of the right stock analysts catch wind of this repeated incompetence after the U127xA debacle then Keysight's stock is in for a pounding.A half-arsed de-specification of the product is not enough. You need to:1) Proactively tell all affected customers about the problem.2) Explain the problem honestly, fully and clearly. People with this kit in production use have to be able to evaluate what action they have to take. People can't just turn production lines off if they are affected by this. At the same time, they also need to know of there is a genuine safety issue or measurement confidence/reliability problems if they do keep equipment in production. And they shouldn't have to waste time and money reactively chasing you to get an explanation.3) Tell people what you are going to do to fix the problem that you created for them. Are they getting replacements? When?And, given that we're doing this again after the U127xA affair:4) Explain what you're going to do to make sure that:(a) Other recent products in the field aren't going to turn out to have similar problems because you've spent too much time and money changing the company name, and not enough time and money on designing and manufacturing reliable multimeters.(b) Future products aren't going to be similarly laden with defects that show up in the field.(c) When or if this happens again you'll move expeditiously to inform customers, promptly explain the problem fully and honestly, and replace any affected products as quickly as humanly possible.As it stands at the moment I have zero confidence with anything with a Keysight badge on the front of it unless it once bore a pukka HP badge and I know the product hasn't changed in the interim.Keysight management ought to have figured all of this this out for themselves, but if they can't then I and "Mr. Cluebat" are available at our usual extortionate consultancy rates to explain it to them. Oh, and if you decide to change the company name yet again (after this you may need to) may I suggest "HalveTheSpec".Yes, I know that amongst the serious stuff I've been a bit sarcastic, but having to say this stuff again can make you feel a bit edgy.

author: d-smes
author_rank: Regular Contributor
timestamp: March 29, 2017, 01:06:11 am
content: What's USA warranty for "defect"? I know this is a "design defect" and most warranties only state "manufacturing defects", but thought I'd ask. I'm outside the one year mark, so suspect I have no warranty claim. Can anyone confirm?

author: TheSteve
author_rank: Unknown
timestamp: March 29, 2017, 01:23:54 am
content: Warranty on the 3446x/70A series is 3 years.This is quite disappointing. I bought a U1273A and it turned out to have the conducted interference issue. I bought a new 34461A and now I've lost 40% of the potential range it can measure voltage(albeit at the high end where I rarely use it).

author: wraper
author_rank: Unknown
timestamp: March 29, 2017, 01:36:10 am
content: Quote from: d-smes on March 29, 2017, 01:06:11 am3 year warranty. Also on previous instances if there were any widespread issues, Keysight fixed them for free even out of warranty period.

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: March 29, 2017, 01:58:39 am
content: Keysight has always provided me excellent support in the past, I have no doubt they'll take care of this issue.Besides, this is such a cut and dry manufacturing defect, they must know that in the case of a class action lawsuit, they'll not only end up paying up, but they'll take a permanent hit to their reputation.My guess is we'll see a proposed resolution this week.

author: EEVblog
author_rank: Unknown
timestamp: March 29, 2017, 03:11:33 am
content: Quote from: Alex Nikitin on March 28, 2017, 03:41:22 pmWhat's the big deal?How many people need to measure between 600V and 1000V regularly in practice?

author: EEVblog
author_rank: Unknown
timestamp: March 29, 2017, 03:14:50 am
content: Quote from: Cerebus on March 29, 2017, 12:44:39 amHow do you know they don't have such a plan?They would have hadno choicebut to change the specification, as they have sold countless units already. The specificationsshouldbe changed to reflect the actual units that have shipped and are currently in stock around the world.For example, a user who just bought a unit would download the spec sheet to find out what the maximum specs are before they go use it for such a purpose. You can't leave those people hanging, so changing the specs right away was the right thing to do.Don't read any more into that.Coming out with a revised design, fix, recall, refund offer, or whatever is another issue entirely.I have no doubt theyknowit's a big deal and are working on a solution.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 29, 2017, 07:15:57 am
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amI suspect many more than just me and HighVoltage, who described the problem very well.CheersAlex

author: Messtechniker
author_rank: Frequent Contributor
timestamp: March 29, 2017, 07:56:37 am
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amMe, for one, not ever. Because I will never ever shoot more than 100V up its sockets.In my case to start with it would suffice if KS would send me stickers for my 3465A adapting/correcting the fontand rear panel labelling as well one to stick on the manual.Thereafter followed in due time by a firmware version which deals with the restrictions as far as measurements and calibration for the high voltage ranges are concerned.

author: 0xfede
author_rank: Regular Contributor
timestamp: March 29, 2017, 08:13:40 am
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amThe deal is that they cannot downgrade specification and ratings by 40% when they want.I have measured voltage in excess of 600VDC just occasionally with it and now I don't know how much reliable the instrument is.And the fact that I discovered the addendum because TheSteve pointed it and I was not warned directly by Keysight nor Microlease.Best,0xfede

author: FivePoint03
author_rank: Regular Contributor
timestamp: March 29, 2017, 09:52:08 am
content: I DO need to measure very stable voltages up to 1000V (power supplies and amplifiers). It is of course preferable not to use dividers unless you have to. I'm really not happy about this.... I'd return my 34465A but I've spent money on the MEM and DIG options and have BenchVue as well. What a mess!Keysight should be given a chance to do the right thing. For me that would be a complete refund of meter and license options or provide a swap for a meter that meets the spec. I bought it for.As for whether it's the PCB itself or some component causing the issue I think it could be either.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 29, 2017, 11:22:50 am
content: I've just received an email with the latest Keysight Infoline Support Web update. Nothing in it on this issue.CheersAlex

author: HighVoltage
author_rank: Super Contributor
timestamp: March 29, 2017, 11:40:03 am
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amWell, for me that is a huge deal.I have many 34461A in the field with customers, integrated in to test stands and they are all certified and being used for the DC range up to 1000 Volts. The certification is within the automotive TS16949 certification and several ISO specifications. These instruments are listed with serial numbers and cal certificates in those specifications and can not just be removed and replaced. This would cause a chain reaction of complete new certification of the full test stand.It really is a nightmare that I see coming here and right now there is no solution. I might have to replace them all by a 34401A.Hmm, but where will I get those, since they are out of production?I am looking forward to an answer by Keysight.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 29, 2017, 11:45:16 am
content: I think an interesting question is what the nature of the "damage" is.If it something which is an obvious failure, as opposed to a possible loss of accuracy with no indication, that's probably not actually a huge deal, assuming they deal with any failures under warranty.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 29, 2017, 11:57:11 am
content: Quote from: HighVoltage on March 29, 2017, 11:40:03 amBoth 34401 and 34410 are still available (until stock is exhausted) here in the UK from RS and Farnell.CheersAlex

author: alm
author_rank: Super Contributor
timestamp: March 29, 2017, 12:02:43 pm
content: Keep in mind that it took Keysight a couple of years to identify this, even though many of the instruments will be on yearly calibration cycles using a quality management system that keeps track of the number of out of spec results for each range. If 50% of the units were out of spec in the 1 kVDC range after the first year, they would have responded sooner. So it is either a problem that will only occur in a small fraction of instruments (but not limited to a particular serial number range), takes a couple of years to develop, or something that only happens in rare cases (like instruments connected to > 600 VDC for prolonged periods of time).

author: HighVoltage
author_rank: Super Contributor
timestamp: March 29, 2017, 12:15:28 pm
content: I had my four meters hooked up to 1000 V DC over night and I see no problem at all.May be not all meters are effected?

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 29, 2017, 12:28:26 pm
content: Quote from: HighVoltage on March 29, 2017, 12:15:28 pmIt is not an instant failure, otherwise it would have been noticed a long time ago. It appears that the probability of a "damage" (what kind of a "damage"/failure is still unknown) if you go over 600V DC 440V AC is sufficiently high to change the meters rating. First and foremost Keysight should explain the nature of this problem in detail, otherwise it is not even clear what kind of a risk we are looking at and how high that risk is. And there are more questions to ask. For example, if one of your meters would fail that test at 1000V DC - would they repair/replace it if you now knowingly went over the maximum allowable voltage?CheersAlex

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 29, 2017, 12:43:57 pm
content: We definitely need some clarification on the exact nature and extent of the "damage".It is quite possible they don't know the exact cause or circumstances that maks it happen, but they must know the result and affected component(s).

author: TiN
author_rank: Super Contributor
timestamp: March 29, 2017, 12:45:48 pm
content: Thanks for the thread.Also BTW 3458A is NOT rated to 1000VAC, only special version 3458-H01 option is, which has own DCV A1 and A11 (switch/protection) PCBAs.

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: March 29, 2017, 02:49:04 pm
content: Quote from: HighVoltage on March 29, 2017, 12:15:28 pmWhat do you expect to see for a problem described as causing damage "over the life" of a unit used at these voltages?On another note, as to whether warranty claims for damage done by applying high-voltage post Keysight spec change....well, they'd have to prove you knew and did it anyway. Which would be a difficult thing to prove, unless you did it, took pictures, and posted in the forum discussing the notice from Keysight.

author: HighVoltage
author_rank: Super Contributor
timestamp: March 29, 2017, 03:26:27 pm
content: Quote from: GlowingGhoul on March 29, 2017, 02:49:04 pmI have been using these meters a lot over the years at just below 1000V, so they have aged over their life so far.This was the first time I hooked them all in parallel to see if they show any sign of differences and they don't.On the other hand I can not stop my customers from using them right now at just below 1000V, no matter if Keysight releases an updated note or not, this would mean production STOP !

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: March 29, 2017, 03:55:44 pm
content: Quote from: HighVoltage on March 29, 2017, 03:26:27 pmI doubt they could deny you service even if you did use it according to the old spec. A consumer doesn't have an obligation to accommodate a change to specifications after the sale.

author: Zucca
author_rank: Unknown
timestamp: March 29, 2017, 04:09:21 pm
content: Com'on KS, just release the schematics and we will make them 1500V, and everybody will be happy again.

author: Dwaine
author_rank: Frequent Contributor
timestamp: March 29, 2017, 05:36:05 pm
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amI do with old tube amps and tube power supplies. There are still some us around.. I'm rebuilding a Heathkit SB101 now. Back to the Rigol DM3068 again.

author: TheSteve
author_rank: Unknown
timestamp: March 29, 2017, 05:46:29 pm
content: Maybe there will be a flood of cheap 3446xA's, I'll sell my 34411A and pickup another one.I am sure we will hear more from Keysight shortly.

author: Cerebus
author_rank: Super Contributor
timestamp: March 29, 2017, 07:06:43 pm
content: Quote from: EEVblog on March 29, 2017, 03:14:50 amThe silence.If it was my business I'd make damn sure that the bad news, the specification change notice, was accompanied by good news, even if it was as little as something like "Detailed plans for how Keysight will address this problem for units in the field will be published on or before the nth of m-month 2017. In the meantime fuller details of the issue can be seen athttp://somewhereand that page will be updated as more information becomes available."Quote from: EEVblog on March 29, 2017, 03:14:50 amWhat's a big deal is handling it as ham-fisted a way as they handled the previous handheld meter issues. it doesn't take any longer to offer some useful information to your customer than it does to issue the specification update. You might not have a full plan, a full solution, but you can offer what you do currently have. If you know enough to know that the meter's borked then you know enough to tell customers how it's borked and whether you're going to see them right.

author: 0xfede
author_rank: Regular Contributor
timestamp: March 29, 2017, 09:11:53 pm
content: Today I was contacted by Microlease and I've been told that there should not be safety problem with the instrument. The employee also stated that he don't know exactly what the problems are and which policy Keysight will adopt.De facto no answers were given but he promise that in the next days I'll be called again as soon new informations arrive.Best,0xfede

author: Dwaine
author_rank: Frequent Contributor
timestamp: March 30, 2017, 12:57:00 am
content: I think that the failure will happen within warranty period. If not and it was later in life for the meter. Keysight would just wait for the slew of repairs to show up.I hope it just a few components that can be replaced with another manufacturer.These instruments are not cheap eBay specials. Already noted that these are sitting on production lines. So the cost of this incident is larger than say the u127x situation.I

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: March 30, 2017, 02:44:32 pm
content: So Keysight seems to have decided to allow this issue to fester for another day. Very disappointing.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 30, 2017, 04:30:43 pm
content: TDNBW.CheersAlex

author: TheSteve
author_rank: Unknown
timestamp: March 30, 2017, 08:10:55 pm
content: No service notes released on the issue, no reply to Dr Frank on the Keysight forum. They were very fast to update all references on the Keysight website though. It now advertises them as a 34401A replacement but with 600 VDC maximum - so only sort of a replacement.I just realized I have AC voltages over 440 at the shop that I guess I can't measure anymore.

author: carl_lab
author_rank: Frequent Contributor
timestamp: March 30, 2017, 08:32:11 pm
content: QuoteWow, that's a very bad joke...If that's true, our company probably won't buy these Keysight DMMs any more.34461A/465A were announced to be successor of 34401A/410A...We bought many as a replacement for no more available 34401A/410A.I will continue calibrating them at 1000 VDC as originally specified, because we received no call-back nor other official info about reduced spec. Maybe I should increase test voltage to 1100V or 1200V to ensure failure of weak units within warranty period?Of course, if some units die, I'll send them for warranty-replacement...

author: HighVoltage
author_rank: Super Contributor
timestamp: March 30, 2017, 08:42:51 pm
content: Today I contacted the German distributor where I bought my instruments but they could also not tell me anything specific.In the meantime I will be continuing using them for up to 1000 V DC, because I do not have a real other choice here.

author: Tom45
author_rank: Frequent Contributor
timestamp: March 30, 2017, 08:54:58 pm
content: Quote from: TheSteve on March 30, 2017, 08:10:55 pmThe datasheethttp://literature.cdn.keysight.com/litweb/pdf/5991-1983EN.pdfhasn't been updated:

author: carl_lab
author_rank: Frequent Contributor
timestamp: March 30, 2017, 08:55:55 pm
content: I want HP back...

author: wraper
author_rank: Unknown
timestamp: March 30, 2017, 09:20:58 pm
content: This tread is becoming a cry fest.

author: corn11
author_rank: Regular Contributor
timestamp: March 30, 2017, 10:19:12 pm
content: Hmm, I've just thought about selling my 34401A and getting a 34461A.Although this problem seems to be more severe than others, I think they'll fix it. In the past there were also some issues with the 34401A and other meters (as highlighted here before) and they ever came up with a decent solution.For example look at the service notes for the 34401A, often there were only a limited number of units affected sometimes only one or two and they've took care of it and wrote a SN. As pointed out before by various others this might also be the case here. Other companies might have completely hidden such problems, just sitting there and waiting for a customer to come up with a known issue.

author: kaz911
author_rank: Super Contributor
timestamp: March 30, 2017, 10:32:16 pm
content: It is all a numbers game. How many will in reality request a replacement - even on 100% public newspaper headline recalls for consumer products - very few requests a replacement or act on the recalls. I think the biggest recall "success" was Samsung as they ? disabled peoples phones if they did not respond? (Not certain about it but I seem to remember something like that...) - but I am certain they did not get all of them back.But Keysight does have some recent stats on the Multimeters to base their numbers onso I have faith in the Keysight guys & girls. I do not often measure above 400V A/C but it does happen but I won't force it into "oblivion". And if it is only a component issue - then it would be solved very quick - so I think they might have to re-spin the boards to make it work - which is why it will take a while before new ones are out.But I do love my 34465a... I just wish they would make a real dual or triple channel versionMine runs for weeks logging data.

author: Faith
author_rank: Unknown
timestamp: March 31, 2017, 12:20:59 pm
content: Quote from: wraper on March 30, 2017, 09:20:58 pmWell, I own a 34465A (w/ DIG+MEM) and while I pretty much never go beyond the 600VDC/440VAC realm I do realise that I myself am not representative of everyone else's usage scenarios which are expected out of this DMM and can thus sympathise with anyone who is more than a little bit cross at this "slight" change in specification.Okay, maybe not so "slight." We're "only" talking about a drop from 1000VDC/750VAC all the way down to 600VDC/440VAC on one of the instrument's key measurements.Sarcasm aside though, my issues pretty much boil down to the following two facts:(A) That I am finding out about this issue on this forum first instead of my email inbox which my Keysight account containing my 34465A has the address for, which speaks volumes about Keysight's ineptitude where customer communication is concerned, and;(B) That this is the second time in half a year or so a Keysight DMM I own is affected by a post-purchase change in specification (the other being a U1273A).So I think it's fair to say that I am a somewhat less-than-thrilled Keysight owner right now, especially given that Keysight's original solution to "tackling" the issues surrounding the U1273A DMM was far from optimal. Doesn't really instil a lot of customer confidence, even if you're predominantly unaffected. Still though, love using my 34465A.Edit: So, uhm, Keysight; are we going to get any stickers to update the front panels of our DMM's? >.<"...

author: Messtechniker
author_rank: Frequent Contributor
timestamp: March 31, 2017, 04:36:52 pm
content: Quote from: Faith on March 31, 2017, 12:20:59 pmAnd for the rear panels and the manuals for that matter.How about throwing in a free calibration too when not needing to go above 600VDC/440VAC.

author: wraper
author_rank: Unknown
timestamp: March 31, 2017, 05:09:51 pm
content: Quote from: Faith on March 31, 2017, 12:20:59 pmSo, I guess, they should not had published this info ASAP before they had a complete plan how to deal with this situation. A lot of tears of crybabies would be saved. Was it, say, Rigol, you'd never ever knew that this issue existed at all.What is your "optimal" solution? Instantly replacing all affected meters with unaffected stock you don't have?

author: Alex Nikitin
author_rank: Super Contributor
timestamp: March 31, 2017, 05:34:31 pm
content: Quote from: wraper on March 31, 2017, 05:09:51 pmI find your attitude very ... childish, sorry. Anyone who works in a controlled environment and has to comply with standards and regulations, would understand perfectly well what me and other affected members complain about. Sh*t happens, however there are certain expectations of how a decent company like Keysight, should behave in a situation like this. Right now they let down many people not because their meters are faulty and can not meet the advertised specification, but because they are not forthcoming with the information which could be critical for businesses using their products, leaving their customers essentially up sh*t creek without a paddle.CheersAlex

author: Jono427
author_rank: Contributor
timestamp: March 31, 2017, 05:42:06 pm
content: Quote from: wraper on March 31, 2017, 05:09:51 pmDisclaimer: I do not own one of these DMMs, but was considering getting a 1000x for my first scope - I will be watching how they handle this to decide before I but one.Well the addendum was dated March 17th, and they still apparently have still not notified registered owners. As one person put it not having a plan yet for a fix/replacement is fine, but they should probably have given more info about the issue (now bad is taking a 1000v DC measurement) and at a minimum should have sent that to the owners to give them notice that the product is no longer rated as originally advertised.

author: wraper
author_rank: Unknown
timestamp: March 31, 2017, 06:28:49 pm
content: Quote from: Alex Nikitin on March 31, 2017, 05:34:31 pmI find childish all sorts of speculations and assumptions in the recent posts.

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: March 31, 2017, 07:33:51 pm
content: Quote from: wraper on March 31, 2017, 06:28:49 pmThe fault lies squarely with Keysight. They have not given even the slightest indication that intend to do something about this very serious matter. A simple indication that a resolution is being worked on would be professional. As it stands, they are behaving no differently than a company intent on foisting this problem onto innocent customers.

author: Keysight Technologies Rep
author_rank: Contributor
timestamp: April 01, 2017, 04:55:30 pm
content: Thanks to those on this EEV blog thread for the dialog about a standards compliance issue with Keysight Technologies’ 3446XA and 34470A digital multimeters. Your conversation reinforces Keysight’s commitment to address this issue to the satisfaction of our customers. We apologize if this has inconvenienced any of our customers, and acknowledge that this response is coming later than some would have hoped.What we have determinedWhile the product was initially rated at a maximum input value of 1000VDC/750VAC, this has been reduced to 600 VDC/440VAC to allow a component to operate within its rated values. There is no change in the Measurement Category II rating of 300V. The change in the maximum rated input voltage is to ensure the product meets requirements of the IEC61010 standards. Most importantly, there are no safety concerns related to this change.Failure risk very low, no safety riskThe products maintain their performance accuracy, and no failures have been observed up to 1000VDC. While there is the possibility of component failure in using the products above 600 VDC/440VAC, there are no safety risks. Further, there have been no known component-related reliability failures since shipment of these products started in 2013.Confidence in product reliabilityThese products continue to be covered by Keysight’s three-year standard warranty, and effective immediately, we will provide an additional one-year warranty extension to ensure customers can depend on our products.Next stepsKeysight has begun redesigning the 3446XA and 34470A digital multimeters to reinstate the original maximum input ratings of 1000VDC/750VAC. We have set a goal to ship the redesigned products by December of 2017, and will make every effort to begin shipment sooner than that.For more information about the steps Keysight is taking to address this issue, we have posted a service note on the company’s website. To view the service note, navigate to Keysight’s website,https://servicenotes.literature.keysight.com/litapp/SearchSN.do?method=openExternalSNSearch&prodNum=and type in product number 34461A-04. Any customers who require 1000VDC/750VAC testing capabilities can contact a Keysight Customer Contact Center and reference the service note number.

author: wraper
author_rank: Unknown
timestamp: April 01, 2017, 05:37:26 pm
content: Quote from: Flinstone on April 01, 2017, 05:13:26 pmI would be surprised if would not slip. Do they check every datasheet of every component and calculate/measure their voltage/current through them in every possible operating scenario? As said, this does not affect operation at all, and there is no safety risk.

author: carl_lab
author_rank: Frequent Contributor
timestamp: April 01, 2017, 05:52:41 pm
content: Why not simply replace the faulty/weak component?Only answer I could imagine is this component is the PCB...

author: HighVoltage
author_rank: Super Contributor
timestamp: April 01, 2017, 06:37:03 pm
content: Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmThank you Keysight for explaining some more details to us.My own observation is also that I have NO problems at all and my 4 lab units meet specifications perfectly at 1000 V DCI am inclined to continue to use my instruments at up to 1000 V DCIf I contact the service center, what can they offer for me?

author: diyaudio
author_rank: Frequent Contributor
timestamp: April 02, 2017, 11:17:02 am
content: Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmhttps://www.eevblog.com/forum/testgear/keysight-34401a/So, last year I took my last earned cent to buy this instrument see above, How does this news bother me? It doesn't. What can you offer me as compensation? just throw me a FREE licence for benchvue, I would be grateful.

author: plesa
author_rank: Frequent Contributor
timestamp: April 02, 2017, 11:31:18 am
content: Quote from: diyaudio on April 02, 2017, 11:17:02 amYou will receive free warranty:Code:Product that is currently out of warranty will have its warranty extended to 31st March 2018Lot of companies will not publish this kind of note, unless there is reliability of safety risk.QuoteIn various vendors products you can see usage of components outside their operation conditions.1450V test give me confidence that product is OK and we are talking more or less about formal note.BTW: for logging there are much better alternatives than BenchVue

author: SeanB
author_rank: Super Contributor
timestamp: April 02, 2017, 01:08:02 pm
content: I guess they are referring to the input posistor and fusible resistor, which probably is being run out of it's breaking range with over 600V applied, and the redesign is to simply use either a different part with higher ratings, or use 2 in series instead. Pretty much like almost every multimeter manufacturer, but here they want to prevent the input stage going foof if you apply 1kV to it in the high input impedance and it does not autorange fast enough and the resistors have to act as current limiting during the time autorange takes to operate.

author: Cerebus
author_rank: Super Contributor
timestamp: April 02, 2017, 02:54:32 pm
content: Quote from: SeanB on April 02, 2017, 01:08:02 pmIf the design of the 3446x and 34470 are anything like their similar predecessors (34410 and the earlier 34401, for which there are schematics available) there are neither PTCs nor fusible resistors on the inputs. We're talking spark gaps, varistors and relays at the front followed by high impedances and diode clamps.

author: SeanB
author_rank: Super Contributor
timestamp: April 02, 2017, 04:09:43 pm
content: Well then there is a resistor network or relay with relaxed spec, either they had a change of supplier for a nominally identical part, or the spec was quietly changed on them for those parts to derate it.

author: LabSpokane
author_rank: Super Contributor
timestamp: April 02, 2017, 08:42:50 pm
content: Quote from: EEVblog on March 29, 2017, 03:11:33 amYou're correct that most don't measure *nominal* values in those ranges. What most of us need is for the meter to not be damaged by *transients* in that range. If I knew what voltage I was going to read before I connected the meter, I wouldn't need a meter to begin with. I will say that my standard practice is to use a handheld meter before connecting up my bench meter in order to blow up the least expensive device possible if I have a question.The major problems for me with all of this mess are:- This really feels like bait and switch. We all bought meters based on their data sheet capabilities for not just what we wanted to do today, but for work we might do in the future. We bought GENERAL PURPOSE tools, not CDMA site analyzers that we knew would become obsolete in a few years.- Everyone with the affected meters just lost who-knows-how-much on the resale value based on the *perception* that these meters aren't that good - which isn't true of course - but perception becomes reality.- There's no shortage of us with multiple meters. I have two and was thinking about getting another.As for the "solution," the extra year of warranty feels pretty underwhelming, and the MBA that thought that one up can stick it. Affected customers deserve more. Like 50% off on replacement DMMs for customers with registered units up to the number we already own. The MBA won't like it, but that's the cost of a broken promise.

author: The Soulman
author_rank: Super Contributor
timestamp: April 02, 2017, 10:07:30 pm
content: I'm in no way affected by this as I don't have this meter but I'm stumped that there isn't any information released on the actual failure mode??Is the accuracy (slightly??) affected??Or is the input impedance going to rise or does it get lower??Just two examples of realistic failure modes that might have keysight going "meh", but could have BIG impact on some costumers in the real world.For keysight to save the day they have to be much more transparent.

author: Someone
author_rank: Super Contributor
timestamp: April 03, 2017, 03:41:36 am
content: Quote from: LabSpokane on April 02, 2017, 08:42:50 pmWell we already received part of that answer:Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmSo there is no safety problem and the transient protection rating remains the same. From all the information so far its a component being stressed beyond its manufacturers rating but hasn't caused mass failure in the field, or under synthetic testing within the limits described above (1450V withstand etc). Rather than just uprating the parts based on their field experience the spec has been lowered to meet the standards compliance requirements, its a paper pushing exercise and nothing to get worked up over.

author: BravoV
author_rank: Super Contributor
timestamp: April 03, 2017, 05:06:17 am
content: Simple noob question, what is the chance that this will ended up in law suit in the position favoring the plaintiff ?I'm aware that Keysight has army of lawyers to defend them, but still ...

author: Alex Nikitin
author_rank: Super Contributor
timestamp: April 03, 2017, 07:54:16 am
content: Quote from: Someone on April 03, 2017, 03:41:36 amUnfortunately, that paper pushing won't stop here. If a company is using these meters to measure voltages in 600-1000V DC and 440-750V AC ranges, and has to comply with the standards, it is now essentially prohibited from using these meters - for the same very reason Keysight has issued this change notice. Keysight asks customers in that situation to contact them:QuoteHowever, as I understood it, they don't offer a solution, they only offerQuote.CheersAlex

author: Dr. Frank
author_rank: Super Contributor
timestamp: April 03, 2017, 10:48:58 am
content: I checked the latest IEC 61010-1 and IEC 6101-2-030, both are new versions (2017-01-01), replacing the old versions (2010-06-01).Within theseEuropeanstandards, Safety Classes (e.g. II) and voltage ranges are defined:The relevant ranges are (>300 <=600V) a.c. rms or dc and (>600 and <= 1000V) a.c. rms or dc.These ranges require for example different clearances (isolation, jacks, PCB routes,..) and different constant or impulse voltages..For example, the maximum transient overvoltage in CAT II, for 300..600V is 4kV, for 600..1000V it's 6kV.The latter value has been increased (from 4kV) in the new revision of IEC 61010-2-030.Also, the requirements for overvoltage limiting circuits (formerly these were explicitly named: varistors, spark gaps, ceramic capacitors, surge arresters) in the IEC 61010-1 has been increased from only 'suppressing such transients w/o overheating', to additionally 'continue to function properly after the test'.So, here are my two conclusions:The standard sets a.c. rms and dc values are defined as being equal in the same voltage ranges, which is not correct.There is no explicit 440V a.c. range defined anywhere in these standards.Instead, a.c. peak and d.c should be equivalent regarding transients and overvoltage protection.Keysight corrected that fault by specifying 600V d.c. and 440V a.c. rms.Although these standards in the past already defined the same classes and voltage limits, these two above mentioned changes (6kV and further functionality) may not have been given by the momentary design any more.Most probably by reading the AN 34461A-04, there's a single component affected, maybe the spark tube, or maybe also the PCB design (clearances) does also not withstand these higher requirements.These transients do not occur during normal use of these instruments in a laboratory / work bench, so that explains the statement, that there is no (or only small) risk in applying 1000Vdc / 750Vac.I also bet, that older HP DMMs also will not fulfill this standard any more, also other DMM manufacturers will very probably not meet these requirements, if they would read these standards carefully and re-check their instruments.Frank

author: Someone
author_rank: Super Contributor
timestamp: April 03, 2017, 10:52:57 am
content: Quote from: Alex Nikitin on April 03, 2017, 07:54:16 amWhich would be a vanishingly small number of users, the device is in cal for now so you're only stuck if you NEED the equipment to meet 61010 which would be a very unusual regulatory environment but feel free to provide examples which require continual compliance. If you're in that situation you can just use a divider probe and you're back off and running.

author: HighVoltage
author_rank: Super Contributor
timestamp: April 03, 2017, 11:42:47 am
content: Thank you Dr.Frank for your great explanation that makes perfect sense.

author: Alex Nikitin
author_rank: Super Contributor
timestamp: April 03, 2017, 11:59:10 am
content: Quote from: Someone on April 03, 2017, 10:52:57 amWhich would be anyone working in a quality controlled environment. I am not permitted to use in production a measuring equipment outside manufacturer's specifications. Obviously there are workarounds, but sometimes these are not easily applicable or desirable (i.e. a divider will introduce an additional uncertainty and needs calibration etc.).CheersAlex

author: Hensingler
author_rank: Regular Contributor
timestamp: April 03, 2017, 12:25:43 pm
content: Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmMy 3.5 year old (with probably less than 400 power on hours) 34461A died 2 days ago - won't boot. I've been told there is no repair service just replace with new at full price although I am not sure I believe the keysight guy that told me that.Reading this post maybe I am not quite as unlucky as I thought.

author: wraper
author_rank: Unknown
timestamp: April 03, 2017, 12:40:15 pm
content: Quote from: Hensingler on April 03, 2017, 12:25:43 pmThen contact them again and mention service note 34461A-04, as your meter has (or will have) warranty extended to 31st March 2018

author: nfmax
author_rank: Super Contributor
timestamp: April 03, 2017, 01:07:00 pm
content: Quote from: Dr. Frank on April 03, 2017, 10:48:58 amSo maybe the data sheet is changed to reflect the new version of the standard, and the instruments met & continue to meet the requirements of the previous version? Anything contractual should always reference the version of the standard.

author: HighVoltage
author_rank: Super Contributor
timestamp: April 03, 2017, 01:08:17 pm
content: Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmI contacted Keysight Germany today and had a very nice conversation but they could not offer anything new, except for:1. There is no problem using my meters for up to 1000 V DC and my meters will all be covered by full warranty, even if something should go wrong.2. The problem is related to two components on the PCB that are too close in proximity and because of this it requires a design change of the PCB.

author: Tom45
author_rank: Frequent Contributor
timestamp: April 03, 2017, 02:15:25 pm
content: Quote from: Dr. Frank on April 03, 2017, 10:48:58 amI wouldn't expect that meters would have to meet the new 2017-01-01 IEC standard that didn't exist when the meters were designed. Now that the standard has been made more strict a new design is necessary. As was said, mostly a paper pushing issue.Was the updated IEC standard the result of any real problems in the field? Or was it just some desk jockey looking for something to change?

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: April 03, 2017, 02:38:08 pm
content: Quote from: Tom45 on April 03, 2017, 02:15:25 pmIf this change were simply the result of applying a new standard, they would simply say that the equipment meets specs under the standard in force at the time of sale.

author: Tom45
author_rank: Frequent Contributor
timestamp: April 03, 2017, 03:42:16 pm
content: Quote from: GlowingGhoul on April 03, 2017, 02:38:08 pmBut that would mean that they can't sell the meters after the first of this year. So they would need to update the design to keep selling them. Which is what they are apparently doing.It looks like somebody at Keysight wasn't paying attention and didn't notice the change in the standards. Keysight should have come out with an updated design before the new standard went into effect. Not months later as is apparently the case.

author: GlowingGhoul
author_rank: Regular Contributor
timestamp: April 03, 2017, 03:58:52 pm
content: Quote from: Tom45 on April 03, 2017, 03:42:16 pmIt's really straightforward in my opinion:Due to an error on Keysight's part, this series of DMM'a are not capable of providing the capabilities it was represented to have at the time of sale.They may suggest (wink wink) it's ok to use the unit out of (the updated) spec, and not to worry because you have an additional 12 months of warranty. This is hardly reassuring and I don't think too many users will be comfortable exceeding specs.Whether you use the high range of voltages or not, you now own a DMM that is not what it purported to be. It will be worth less at resale. Compensation is in order. I mean, not even an updated sticker for the front panel?

author: Cerebus
author_rank: Super Contributor
timestamp: April 03, 2017, 04:59:31 pm
content: Quote from: HighVoltage on April 03, 2017, 01:08:17 pmThere, that's the thing we needed to be told all along. It's a clearance/creepage issue between two components.Given that information at the start, most of us would have gone, "Ah, OK not a major problem for most practical purposes, I can work around that". It's an engineering explanation of the problem that we can understand and almost instantly answers the questions that most of us would have about the practical implications of this. The only way that could be better would be if they named the components and told us the actual measurements versus the required measurements.Dear Keysight marketing/lawyers - next time you have an issue like this, instead of messing your customers about with cryptic specification changes that hide the real issue, go and ask your engineers "If you personally were a customer, ignoring anything you might think as one of our employees, what would you want to be told?" and then tell your customers exactly the answers that the engineers asked for.

author: LabSpokane
author_rank: Super Contributor
timestamp: April 03, 2017, 08:24:26 pm
content: Quote from: Cerebus on April 03, 2017, 04:59:31 pmExactly this. ^Just tell us the real story and we'll figure it out. I have a very different view of bureaucrats moving the regulatory goalposts (which the EU needs to put the kibosh on immediately) versus an actual design defect.

author: Cerebus
author_rank: Super Contributor
timestamp: April 04, 2017, 12:01:45 am
content: Quote from: LabSpokane on April 03, 2017, 08:24:26 pmSomeone earlier in the thread was mis-attributing the IEC standards as EU ones. IEC stands forInternationalElectrotechnical Commission which is not a EU body. The IEC has existed since 1906, the EEC/EU merely since 1957.

author: LabSpokane
author_rank: Super Contributor
timestamp: April 04, 2017, 12:31:50 am
content: Quote from: Cerebus on April 04, 2017, 12:01:45 amI took it on authority from earlier in the thread that this was an EU driven change. Apologies. That said this feels like an arbitrary ego trip by someone in a rule making body.

author: Cerebus
author_rank: Super Contributor
timestamp: April 04, 2017, 01:03:26 am
content: Quote from: LabSpokane on April 04, 2017, 12:31:50 amIf my experience of how these things are done is anything to go by, it wasn't a 'someone' but six tortuous committee meetings held in six different cities over 10 months. Sometimes these things are arbitrary, sometimes they are intelligently arrived at from experience with earlier versions of a standard that have been in the field for some years. Judging which is which is an open problem.

author: LabSpokane
author_rank: Super Contributor
timestamp: April 04, 2017, 03:21:34 pm
content: Quote from: Cerebus on April 04, 2017, 01:03:26 amOh, I didn't realize you were on my project team. Welcome to the party.

author: Dr. Frank
author_rank: Super Contributor
timestamp: April 04, 2017, 05:24:27 pm
content: Quote from: LabSpokane on April 04, 2017, 12:31:50 amSorry, apologies, that's been me, obviously.I was mislead by the English / French format of these standards, and that the headquarters is in Geneva, Switzerland.The U.S. is of course full member of this organization.Frank

author: FivePoint03
author_rank: Regular Contributor
timestamp: April 11, 2017, 03:08:02 pm
content: As I've already said, I use 1000V input regularly for design verification, and here is my response from Keysight. To say I'm not happy would be a massive understatement.Service note 34465A states:-"For customers that still require 1000VDC/750VAC, please contact Keysight Customer Contact Center and reference to the service note number."Here is the response when I contacted keysight:-"Dear ,Thank you for your enquiry.After consulting with our Repair Centre Manager he has advised that the service notes states “The product maintains its performance accuracy and no failures where observed when units were tested up to 1000VDC. ”So, although we are not recommending usage above 600V if it can be avoided, there have been no identifiable risks associated with using it from 600V to 1000V.I hope that helps.Should you have any further questions please do not hesitate to contact us.Best regardsKeysight Technologies UK Limited"

author: agdr
author_rank: Unknown
timestamp: April 11, 2017, 09:30:56 pm
content: Quote from: FivePoint03 on April 11, 2017, 03:08:02 pmWOW!That is unreal.Well their reply just ruled out buying a Keysight meter for me. I had decided the Fluke 8846A's were getting a bit old in design but I'm back to the Fluke. I won't deal with customer (dis)service like that. Pretty clear they are trying to avoid a costly recall, without realizing the damage they are doing to their brand makes the cost of a proper recall look like a drop in the bucket.Thanks for sharing!

author: bson
author_rank: Unknown
timestamp: April 12, 2017, 01:50:28 am
content: Ask them what they DO recommend you do.

author: kcbrown
author_rank: Frequent Contributor
timestamp: April 12, 2017, 02:29:50 am
content: Quote from: Cerebus on April 03, 2017, 04:59:31 pmWell, sort of.The other question that hasn't been answered is whether the clearance distance between the two components in question met the original spec the meter was designed under (or, perhaps, some version prior to that -- implying that no real error was originally made) but somehow doesn't meet a later/current one, or whether it has always been out of spec from the beginning. These are two very different scenarios, and I don't see any real way of determining which is the case.If it's just a problem with it not meeting the current standard, then using the meter at higher voltages clearly shouldn't pose any issues at all, except perhaps regulatory ones. But if it never met any of the standards, then it raises the question of whether or not the meter will meet its accuracy spec at higher voltages. Saying that it can be used at those higher voltages doesn't automatically imply that it'll meet its accuracy specs at those higher voltages.Given the totality of the circumstances, and the testing that went into the meter prior to its release (it clearly was characterized with its current design), I suspect we're looking at a regulatory issue only, and that accuracy and safety are not actually impacted by it.QuoteYep. This.

author: FivePoint03
author_rank: Regular Contributor
timestamp: April 13, 2017, 06:39:58 pm
content: OK got this reply today:-"Dear *****,Thank you for the clarification.I'm pleased to advise that after a rigorous and thorough investigation, Keysight have determined that the existing product design supports the original product measurement voltage of 1000VDC/750VAC.This is because subsequent re-evaluation and re-assessment of the product design architecture across the relevant components have proven that there is sufficient protection that meets the IEC61010 safety standards requirements. Keysight concluded that while the original safety report incorrectly stated the safety ratings of a component, the safety measures designed into the equipment are not compromised. This assessment was validated by testing and Keysight have confirmed the maximum measurement voltage of 1000VDC/750VAC is appropriate.Keysight will continue to offer the extended one year warranty on the units impacted in the serial number range and shipments from Keysight from 2013 until 30th April 2017.I trust this resolves the matter from your side but please contact me with any further questions or concerns.Best regards,****.Keysight Technologies UK Limited"

author: HighVoltage
author_rank: Super Contributor
timestamp: April 13, 2017, 06:51:24 pm
content: WOW!What now, Keysight is retracting the service note with reduced voltages?Just yesterday I had a big meeting with one of my larger customers and we agreed to use older 34410A meters instead, until the revised 34461A meters would be available by 12/2017.What a mess !And why would Keysight not step up and let us know directly here at the forum, if such a significant change was made again!

author: Cerebus
author_rank: Super Contributor
timestamp: April 13, 2017, 06:59:20 pm
content: Quote from: HighVoltage on April 13, 2017, 06:51:24 pmBecause they seem to be incapable of learning from their previous mis-steps.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 13, 2017, 07:06:50 pm
content: The notice is still on the website - that answer isn't 100% clear that they are actually withdrawing the notice.Seems a bit of a cock-up all round - were they originally mistaken, or have they realised it would be such a screw-up that they've managed to "re-interpret" the requirement.The only way they can preserve credibility is to publish more details of the actual issue for others to examine, or maybe get it certified by an independent test house.

author: Fgrir
author_rank: Regular Contributor
timestamp: April 13, 2017, 09:27:02 pm
content: Quote from: FivePoint03 on April 13, 2017, 06:39:58 pmSo we have two weeks left to pick up one of these meters with a free extra year of warranty?

author: Joel_l
author_rank: Frequent Contributor
timestamp: April 13, 2017, 09:32:27 pm
content: Except the data sheet on the website has the lower voltages, so you might be buying it as is.Quote from: Fgrir on April 13, 2017, 09:27:02 pm

author: Fgrir
author_rank: Regular Contributor
timestamp: April 13, 2017, 09:37:35 pm
content: Quote from: Joel_l on April 13, 2017, 09:32:27 pmYeah, but if they are going back to their original spec...

author: Keysight Technologies Rep
author_rank: Contributor
timestamp: April 14, 2017, 06:25:27 pm
content: Hello EEVbloggers. We are jumping in here to make a few statements. We had planned to wait for confirmation from a third party safety certification agency regarding the 3446xA and 34470A digital multimeters before finalizing our response to the community. However, since what was shared in two of these blog submissions is an incomplete, internal draft of our communication, we want to bring you up to date with where we are in the process. Today, we submitted information to the agency, and expect to hear from them before the end of this month. We will share the outcome with you as soon as we receive it.

author: HighVoltage
author_rank: Super Contributor
timestamp: April 15, 2017, 09:08:12 am
content: Quote from: Keysight Technologies Rep on April 14, 2017, 06:25:27 pmThank you Keysight for a small explanation.Please includedetaileddescription of the problem and how it was solved, when you are ready.Otherwise, some of us might look really stupid towards our customers with this mess.

author: EEVblog
author_rank: Unknown
timestamp: April 15, 2017, 10:35:44 am
content: From the teardown photo of the 34461A I'd suspect it's an internal trace(s) causing the issue.

author: carl_lab
author_rank: Frequent Contributor
timestamp: April 16, 2017, 08:44:45 am
content: Quote from: EEVblog on April 15, 2017, 10:35:44 amWrong 11A fuse at 3A location!

author: Messtechniker
author_rank: Frequent Contributor
timestamp: April 16, 2017, 09:20:33 am
content: Quote from: carl_lab on April 16, 2017, 08:44:45 amApparently not as per Operating and Service Guide.Here the quote from it:"Both internal current path fuses are part number 2110-1402, 11 A, 1000 V, fast acting."

author: HighVoltage
author_rank: Super Contributor
timestamp: April 16, 2017, 09:21:31 am
content: Quote from: carl_lab on April 16, 2017, 08:44:45 amMay be Dave replaced them wrong after the tear down ?

author: Lajon
author_rank: Contributor
timestamp: April 16, 2017, 09:25:18 am
content: No the 3A path has two fuses with the 3A fuse on the rear panel and one internal 11A./Lars

author: PA0PBZ
author_rank: Super Contributor
timestamp: April 16, 2017, 09:31:51 am
content: Yes, it doesn't indicate the fuse rating but the path it is in, the other 11A fuse is marked 10A.A bit confusing I agree.

author: Jwalling
author_rank: Unknown
timestamp: April 16, 2017, 10:54:12 am
content: Quote from: carl_lab on April 16, 2017, 08:44:45 am3A TERM. I think the silkscreen is referring to the current input jack and it's rating.

author: carl_lab
author_rank: Frequent Contributor
timestamp: April 16, 2017, 11:25:06 am
content: OK, I was wrong.But very useful, that you have to read the user manual for replacing the fuse...

author: matemathieu
author_rank: Contributor
timestamp: April 20, 2017, 02:05:33 pm
content: I went in town today to get one of those!Then I heard about the problem, it's quite a bummer, they are rebadging the whole production!Maybe they'll have to make a new series to fix that issue, because the competition makes it up to 1kV.

author: matemathieu
author_rank: Contributor
timestamp: April 20, 2017, 02:25:35 pm
content: Well, actually it was said on the second answer of the thread.Sorry

author: Hensingler
author_rank: Regular Contributor
timestamp: April 21, 2017, 12:43:32 pm
content: After some argument Keysight agreed to repair (by unit exchange) my dead 34461A under the extended warranty associated with this issue. The exchange unit looks like it could be brand new but didn't come in new packaging with leads and documents. It looks like this.

author: HighVoltage
author_rank: Super Contributor
timestamp: April 21, 2017, 12:46:51 pm
content: Quote from: Hensingler on April 21, 2017, 12:43:32 pmThat just looks very sad!

author: The Soulman
author_rank: Super Contributor
timestamp: April 21, 2017, 01:37:10 pm
content: A crappy sticker and it isn't even on straight..@Hensingler: Was the failure of your unit related to high voltage use?

author: wraper
author_rank: Unknown
timestamp: April 21, 2017, 02:00:54 pm
content: Quote from: The Soulman on April 21, 2017, 01:37:10 pmIt basically asks to be "upgraded" to the higher ratings underneath.

author: Hensingler
author_rank: Regular Contributor
timestamp: April 21, 2017, 02:50:07 pm
content: Quote from: The Soulman on April 21, 2017, 01:37:10 pmNo. For the first time in a few weeks I pressed the power on button and it just showed a Keysight logo.That was the day before the 04 service note was issued. I was unlucky that the meter died 6 months out of warranty, unlucky to find the repair cost was 95% the price of a brand new meter, then slightly lucky to find Keysight have extended the warranty over this voltage issue and after some argument it was repaired FOC.

author: R005T3r
author_rank: Frequent Contributor
timestamp: April 23, 2017, 09:40:42 am
content: Quote from: HighVoltage on April 21, 2017, 12:46:51 pmAbsolutely!

author: Dwaine
author_rank: Frequent Contributor
timestamp: April 23, 2017, 11:45:08 pm
content: Maybe Keysight will start selling the stickers online to fix the issue. I'm so glad I'm not wrapped up in this one with real customers. Makes the u1272a situation laughable.I'm real interested in people stories how they will handle the assembly lines test setups with no down time and their customer relationships. Ok. The meters are now rated differently for the voltage specs. But there are a ton of these meters installed in some serious applications with the expectation and certification of a higher spec.Reading the messages and replies. I was thinking the whole time "What do you do?"

author: FivePoint03
author_rank: Regular Contributor
timestamp: April 24, 2017, 06:42:33 am
content: Quote from: FivePoint03 on April 13, 2017, 06:39:58 pmAs the Keysight web site still shows the downgraded spec. I've sent an email today asking for an updated spec. sheet to support this message. It seems hard to imagine that the spec. will suddenly be restored - but I guess time will tell!

author: HighVoltage
author_rank: Super Contributor
timestamp: April 24, 2017, 09:10:03 am
content: Quote from: Dwaine on April 23, 2017, 11:45:08 pmI decided with some of my customers to use the 34410A meter instead in the assembly test line.But then - based on the above email statements - it seems Keysight might retract the downgrading.So, we stopped the 34410A implementation and now we are waiting until the end of the month to have a final word from Keysight.Unfortunately, I think the people at Keysight did not think this issue all the way through to the consequences for their customers.The assembly test lines I am involved in, are officially certified and one can not just change specifications.Essentially this would mean to stop the production line and wait for a solution.Who will pay for that?In my lab I have no problem at all, I just keep using the DMMs as before (up to 1000 VDC) and I got the OK, from Keysight for that.But there might be assembly and testing lines that are much more critical than my customers.What will they do?I am really looking forward to a final statement from Keysight AND a complete disclosure of what was really going on.Otherwise I will look really stupid towards my customers!

author: Dr. Frank
author_rank: Super Contributor
timestamp: April 24, 2017, 10:18:24 am
content: My question in the Keysight Support Forum has been partially answered by tomc like this:"This happened because the regulatory department reclassified a key part to the lower maximum voltage. A redesign to fix this is in progress."This statement is a bit strange, as the IEC61010 gives requirements about complete devices, but not about single components.Anyhow, if this failing component is NOT the PCB itself, there are not so many possible parts (of the input path and input protection) left.Comparing pictures of 34410/411A to those of 34464A/470A reveals, that these components are very probably identical.. I already assumed, that KS re-used great parts of the 410A/411A schematics for the 46xA / 470A.Consequently, this crucial component will probably also affect the 34410/411A HV specification.Would be bad news for using the 411A for 1kV applications..Frank

author: FivePoint03
author_rank: Regular Contributor
timestamp: April 25, 2017, 10:55:38 am
content: Ok it really seems they are going to do a u-turn:-"Dear *****,Thank you for your email.We have checked with our division, who advise the Keysight website is due to be updated with this information next Monday 01st May.Best regardsKeysight Technologies UK Limited""Hi ****,I’ve been monitoring the Keysight web site with regards to this issue. I’m not happy with your response that the unit still supports 1000 VDC – whilst the website and data sheet still say otherwise. Can you confirm there are plans to fully retract the downgrading of the specification? In that case please could you email me a specification for the DMM that reinstates the 1000V measurement capability as soon as possible?Thanks*****"

author: Keysight Technologies Rep
author_rank: Contributor
timestamp: May 01, 2017, 02:15:19 pm
content: Hello EEVblog contributors and followers.As we mentioned in mid-April, Keysight submitted detailed information about the 3446xA and 34470A digital multimeters to an independent safety certification agency. The agency has confirmed to us that there are no safety or compliance concerns in restating the instruments’ original input rating of1000VDC/750VAC using the unchanged product design. As a result, we are updating the published specifications and resuming shipments of both product families. The updated product datasheets and services notes will be available on our website shortly.We realize this situation impacted many valued customers, and apologize for any inconvenience. We appreciate the input from everyone in the EEVblog dialog – your perspectives and suggestions have been helpful in understanding and addressing the matter. We hope that our actions demonstrateKeysight’s ongoing commitment to safety and compliance with industry standards.

author: nctnico
author_rank: Super Contributor
timestamp: May 01, 2017, 02:21:09 pm
content: So I can safely wipe the '600V DC' velt pen markings from my 34461A then

author: HighVoltage
author_rank: Super Contributor
timestamp: May 01, 2017, 02:26:41 pm
content: Hello KeysightThank you for this U-Turn.These results make me very happy but I don't think you realize how much confusion and hours of meetings this has caused me.At least, I would have expected a full explanation of which parts have been involved. Like a full disclosure !Well, at least those people who have bought a DMM with "sticker" can easily upgrade to the new specs by removing the sticker.

author: Robaroni
author_rank: Frequent Contributor
timestamp: May 01, 2017, 03:46:01 pm
content: OK, so what's the final bottom line on this? We usually don't use the 65A at 1000 volts but should we be cautious? Sounds like some backtracking here from KS. Were they getting failed instruments back? How did this mess start. Geeze!

author: Fgrir
author_rank: Regular Contributor
timestamp: May 01, 2017, 04:19:42 pm
content: Quote from: Robaroni on May 01, 2017, 03:46:01 pmThe thread is only 6 pages, you really could read it you know...

author: Robaroni
author_rank: Frequent Contributor
timestamp: May 01, 2017, 04:32:39 pm
content: Quote from: Fgrir on May 01, 2017, 04:19:42 pmI did!Something doesn't fit, that's why I asked!

author: LabSpokane
author_rank: Super Contributor
timestamp: May 01, 2017, 06:04:19 pm
content: You'll become more forgiving of compliance confusion after you've been through this nightmare a few times. Ambiguous and often arbitrary rules coupled with strong opinions and interpretations make it exceedingly painful in instances like this. I'm just happy this issue is dead.

author: PA0PBZ
author_rank: Super Contributor
timestamp: May 01, 2017, 06:05:39 pm
content: Quote from: LabSpokane on May 01, 2017, 06:04:19 pmAre you sure?

author: LabSpokane
author_rank: Super Contributor
timestamp: May 01, 2017, 06:13:32 pm
content: Quote from: PA0PBZ on May 01, 2017, 06:05:39 pmI'm happy to let it drop. Some here might not. I'd be more irritated if I didn't just spend half my morning on the phone hashing on a similar compliance trainwreck that we thought might be a very high value showstopper. I'm in a sympathetic mood right now.

author: LabSpokane
author_rank: Super Contributor
timestamp: May 01, 2017, 06:46:41 pm
content: Quote from: Flinstone on May 01, 2017, 06:19:00 pmThe official conduit will likely be Keysight.com. Regardless, the person posting here is likely a direct, KS employee. If someone really has an issue that is shutting them down, pick up the phone. KS is here as a courtesy.

author: djnz
author_rank: Regular Contributor
timestamp: May 02, 2017, 11:26:55 am
content: Quote from: LabSpokane on May 01, 2017, 06:46:41 pmAnd yet while the specs were downgraded, Keysight did not bother to inform any people who had those meters registered in their name. It was a simple matter of sending out an email to people whose email addresses they already had and yet that did not happen. Saying "KS is here as a courtesy" would be too generous, I wouldn't let them off the hook so easily.

author: Robaroni
author_rank: Frequent Contributor
timestamp: May 02, 2017, 12:32:29 pm
content: Quote from: djnz on May 02, 2017, 11:26:55 amI agree, we never got notice on our 65A, I'll bet this wouldn't happen with Fluke. They're here backtracking and who knows the real bottom line, did they get a pile of blown up meters in for repair?

author: cjm
author_rank: Contributor
timestamp: May 03, 2017, 12:55:32 pm
content: I see the official service note on this issue has now been updated to reinstate the original 1000V rating :https://servicenotes.literature.keysight.com/litapp/SearchSN.do?method=openExternalSNSearch&prodNum=34461A

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 15, 2017, 07:08:52 pm
content: Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmSo whatever happened to this promise, did it disappear together with the service note? I don't see any additional warranty on the My Keysight page...

author: HighVoltage
author_rank: Super Contributor
timestamp: June 15, 2017, 07:28:59 pm
content: The service note 34461A-04A clearly states the additional 1 year warranty.Just today I wrote a request to Keysight to update the warranty expiration date of my 34470A to reflect this additional 1 year.Will see, what Keysight will answer / do.May be they will only honor this on each individual case, if a claim should be filed.

author: EEVblog
author_rank: Unknown
timestamp: October 16, 2017, 04:55:21 am
content: Straight from the horses mouth!

author: HighVoltage
author_rank: Super Contributor
timestamp: October 16, 2017, 08:38:55 am
content: Thank you so much for this short video.And thank you to John Kenny for explaining it.That is exactly what we here at the forum suspected, that there never was a problem.

author: Cerebus
author_rank: Super Contributor
timestamp: October 16, 2017, 08:43:52 am
content: Quote from: HighVoltage on October 16, 2017, 08:38:55 amIt might have been whatyouexpected, but it's a tad presumptuous to speak for everybody, i.e. "we here at the forum".

author: HighVoltage
author_rank: Super Contributor
timestamp: October 16, 2017, 08:45:36 am
content: True, it was only my personal expectation, after I did my own tests.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: October 16, 2017, 09:18:55 am
content: He wouldn't say which part, but later let slip that it was something in the PSU

author: gwideman
author_rank: Contributor
timestamp: October 16, 2017, 10:38:58 am
content: Quote from: mikeselectricstuff on October 16, 2017, 09:18:55 amOr he might have been following on from earlier in the conversation where perhaps he mentioned that he works on Keysight's high voltage power supplies, and is thus familiar with components (or PCB layout etc) used in high voltage situations.

author: wraper
author_rank: Unknown
timestamp: October 16, 2017, 11:43:19 am
content: Quote from: mikeselectricstuff on October 16, 2017, 09:18:55 amIMO it was implied he is a PSU guy, so he knows a lot about safety. Not that it was in PSU.

author: wraper
author_rank: Unknown
timestamp: October 16, 2017, 11:52:35 am
content: It could be, say, relay. They might notice that insulation between coil and contacts in not good for 1000V insulation. However that would be true only if that was between live and chassis. But in this case it was between live and live, so completely OK.Relays usedhttp://www.mouser.com/ds/2/315/mech_eng_ds-1075856.pdfQuote

author: EEVblog
author_rank: Unknown
timestamp: October 16, 2017, 01:28:18 pm
content: Quote from: gwideman on October 16, 2017, 10:38:58 amYes, John is a PSU guy.

author: HighVoltage
author_rank: Super Contributor
timestamp: October 16, 2017, 01:36:37 pm
content: It looks like John Kenny is the Technology Manager for Keysight's Power and Energy division.He introduced the new E36100 PSU in 2015 in this video:

author: fonograph
author_rank: Frequent Contributor
timestamp: October 17, 2017, 12:01:41 pm
content: I dont like that video,not that its Dave fault,I found it to be waste of time,I didnt really learn anything new from it.Its irritating that he dont want to tell witch part it is.I would be happier if he never went to Dave to make that video,so this thread will just collect dust and it will be forgoten.The fact that Keysight decided to go back to this whole thing yet not reveal what is the suspected part is making me angry.Either tell exactly what it was,or be quiet.I am not interested in any half arsed public relations damage control bs.

author: _Wim_
author_rank: Super Contributor
timestamp: October 17, 2017, 07:00:12 pm
content: Quote from: fonograph on October 17, 2017, 12:01:41 pmAs he stated in the video, they are using “this” part always like that (so based on experience), but probably the numbers do not exactly match (but it is a common practice to use the part like that). Making the exact part number known will trigger a whole new discussion if it is allowed to use this part or not. If even at Keysight it causes big discussion and disagreement, imagine what would happen on a forum like this and others...I concluded from this video that Keysight has a company structure where QA/Safety is independent from engineering and sales (as it should), and this assures that products are always closely reviewed, and this ensures we get a better/safer product.

author: wraper
author_rank: Unknown
timestamp: October 17, 2017, 07:17:37 pm
content: Quote from: fonograph on October 17, 2017, 12:01:41 pmWhy should they? There was no actual problem to start with.Quote from: _Wim_ on October 17, 2017, 07:00:12 pmexactly

author: fonograph
author_rank: Frequent Contributor
timestamp: October 18, 2017, 04:21:04 am
content: Just becose they said there is no problem doesnt make it a truth.Fact is they are using 600V rated part in 1000V circuit to save money and refuse to tell which part it is.Ofcourse they are going to say its "no problem",their profits could suffer,they have been probably cutting cost by using this under spec part for long time,its probably in multiple of their products,if people found out that this was going so long and is so widespread it will severly damage peoples opinion on the company.Someone who is not from Keysight found out about it and was of opinion that this is problem.They lowered the rating,no matter what they claim,if it was really no problem and they were confident in it,the engineers who designed it would instantly confirm that indeed its not a problem and the ratings would be never lowered.The fact that they lowered it shows us that they arent as confident as they pretend to be when it comes to safety of this severly underspeced part."But competitors do it too" so what? I dont care,show me the part! What are you trying to hide? We only heard this from Keysight point of view,they have profits at stake,they have motive to be dishonest and contrary to their no problem narative the fact that they are hiding it from public,that fact that they arent confident in the part as they shown by lowering the spec,the fact that someone neutral who doesnt have horse in race was worried,the fact that they admited to use severly underspeced part makes me skeptical of their claims.If you want to believe them,fine.To me this all seems suspicious and I wont be satisfied with anything they say until they reveal what part it is,if its really ok,then show it if you have nothing to hide.

author: EEVblog
author_rank: Unknown
timestamp: October 18, 2017, 05:30:34 am
content: Quote from: fonograph on October 17, 2017, 12:01:41 pmKeysight didnotcome to me to do this video, John came to do the 2 1/2 hour video interview I'm slowly releasing. He had no idea I would even ask that question, I only asked it because someone in the forum suggested it.QuoteSorry to tell you, but they very likely don't care what you think. You are welcome to protest by taking your T&M business elsewhere.

author: EEVblog
author_rank: Unknown
timestamp: October 18, 2017, 05:37:07 am
content: Quote from: fonograph on October 18, 2017, 04:21:04 amDo you have proof it's "to save money"? or, as I suspect, you are just speculating.They said all the other manufacturers do the same thing, and they have done it for so long that people have forgotten why exactly.This isclearlynot a cost cutting method. For all we know there is only one part that does the job and everyone uses it.QuoteAnd the evidence of them cost cutting anywhere else in the product is were exactly? That kinda makes your suspicion almost certainly wrong.QuoteSo what? That actually tell you quite a lot from an engineering point of view.QuoteThey are likely trying to stop people like you from going ape over a single spec sheet figure that may not be relevant without a ton of other engineering test and historical data that would likely be difficult to comprehend to Joe Average.

author: fonograph
author_rank: Frequent Contributor
timestamp: October 18, 2017, 07:05:05 am
content: """Do you have proof it's "to save money"? or, as I suspect, you are just speculating.They said all the other manufacturers do the same thing, and they have done it for so long that people have forgotten why exactly.This isclearlynot a cost cutting method. For all we know there is only one part that does the job and everyone uses it."""You ask me for proof if using 600V spec part in 1000V circuit is to "save money?"That is common sense! Higher spec parts cost significantly more,all companies use cheapest parts possible to maximize profit. 99% of the time there is under spec part used anywhere,be it electronics,or mechanical maschines,constructing house or anywhere really,it is to spend less money.What proof you have that its not to save money? I dont claim it is to save money,I do claim thats much more likely than opposite and there is no proof that it isnt to save money. Proof that could be easily made if they revelead the part."""They are likely trying to stop people like you from going ape over a single spec sheet figure that may not be relevant without a ton of other engineering test and historical data that would likely be difficult to comprehend to Joe Average."""I cant believe you are blaming general public for being too inexperienced to deserve answer.Average Joe doesnt buy 1200 dollar multimeter.I think the idea that engineering community on average is too inexperienced and hysterical as warranty to hide important facts about use of underspec part is not right.I am noob,I admit it,but I dont go ape for irrational reasons when I discover some product uses under spec parts in it.For example Rigol uses under spec ADCs in their scopes,I didnt go "ooo!!! Rigol uses under spec ADCs ooOH my god WORST T&M MANUFACTURER EVER NEVER GOING TO BUY FROM THEM AGAIN OOOOOOO!",I was more like "k lol".Using underspec parts alone doesnt concern me at all,hiding the part despite many people wanting to know what it was,that raises all kinds of red flags for me.And yes yes,Keysight doesnt care about what I think,but I am not alone who is curious what part it is.

author: rodpp
author_rank: Frequent Contributor
timestamp: October 18, 2017, 02:30:58 pm
content: It seems like Keysight knows from experience that there is no problem with that part (or parts) but is afraid to unveil it. Could be because there is no data to support their position or that their data (part specs, test results, etc) could be questionable.Or maybe there is enough data to technically prove that everything is ok and Keysight just decided not show it, even it being a security related issue. If they did that, I can't understand their behavior.Certainly if there is a part with questionable specs, soon or later it will become public, Keysight wanting or not.My personal opinion is that there is nothing wrong and Keysight is sure about that. If they have data to support it, or if they are sure only from experience, I don't have a clue. I really don't believe that Keysight would occult a potential security flaw after issued a spec change and reverted it, if they reverted it is because they are sure there is no problem. Other than that could be too much risky.

author: razberik
author_rank: Frequent Contributor
timestamp: October 18, 2017, 04:06:10 pm
content: Calm down fonograph. Soon or later, community will discover which part it is.When this generation of DMM is available to hobbysts, persons like TiN would evaluate it.There are so many information about other equipment which are not directly from manufacturer.

author: fonograph
author_rank: Frequent Contributor
timestamp: October 18, 2017, 04:25:15 pm
content: I want to apologize,I was making my first message about this when Dave posted just the first video,I didnt know that there is the long video and that this was just short part of it.It looked to me like Keysight send him just to do that 4 minut video,so I take my words back regarding acusation from my side that its "damage control bs".That being said,I stand behind my logical analysis of this happening.It might seem from PC screen that I am hating on Keysight,actualy they are my number 1 favorite electronic test equipment brand with Rohde Schwarz close second.While this might seem like red flag,overall Keysight in my eyes have least red flags,no manufacturer is perfect 100 percent all the time,I still believe they might do the right thing and come clean and tell what part it is.

author: _Wim_
author_rank: Super Contributor
timestamp: October 18, 2017, 06:20:25 pm
content: I think the following has happened (speculation only):- QA/Safety got notified of a potential issue- They checked the specs (purely on numbers), and contacted the engineering department- The engineering department did not have an "approved written rationale" or "documented evidence" why is was ok to use this part in this configuration (because they always used it like this, and the original design decisions were not documented or lost)- According to procedure, QA/Safety has X days to issue a field alert (typically 3 days)- That time was too short for the team from engineering to prove they were correct (like explained in the video, they were also benchmarking others who do this the same way, but this costs time to organize and document a benchmark)- Hence the field alert was issued by QA/Safety- After some hard work from engineering they succeeded in convincing QA/Safety that the design was ok after all- The alert was cancelled, but the damage was already done...But, as this issue has been in the public, and no changes were made by Keysight and the culprit part was not made public, they must be really sure about their entire product. Imagine a safety issue would happen in the future, everybody will say that they “knew” about this, and did not act on it (which is a lot worse than being “surprised” by an “unknown” fault)So I would say their safety/quality system works as it should (safety first), and I have no doubt the product is safe. But off course, this is only speculation on my part from seeing similar thing happen in other industries…

author: Someone
author_rank: Super Contributor
timestamp: October 18, 2017, 10:07:11 pm
content: Quote from: EEVblog on October 18, 2017, 05:37:07 amOr it could be that the stresses across the part(s) only exceed a specification in transient or fault conditions (bootstrapped etc) where the part is used beyond its paper specification but has no safety issue to the user. These are the sorts of difficult areas where a quick look at something could appear dangerous until all the requirements and failure modes are considered. That or as you say many parts don't have transient specifications unless you collect the data yourself which then becomes valuable proprietary information.

author: EEVblog
author_rank: Unknown
timestamp: October 18, 2017, 10:18:08 pm
content: Quote from: fonograph on October 18, 2017, 07:05:05 amRight there is your problem. If you were actually experienced in the industry then you would know that over-speccing parts happens a lot, andfor very legitimate engineering reasons.In my 121GW multimeter for example we are using a chip below it's rated voltage rail specification. We have the OK from the manufacturer to do this and have done extensive testing to ensure it works fine. It is most definitelynotfor cost reduction reasons.There can be many reasons to do this, too many I couldn't even explain them all, but the most likley in this case is that either:1) There is no other part that does the jobor2) This is best part that does the job based on a variety of specs. It's not always possible to find the best component.And the engineering cost of evaluating all this would be oodles more than any supposed "cost saving" you are hounding on about.QuoteYou do realise that by Rigol doing that (and testing the parts to ensure they worked)changed the entire low cost test and measurement industry!I hope that in time you'll learn some respect for what's possible in engineering and the challenges faced by companies in product design. It's not all about the bottom line.QuoteSure we'd all love to know, but once again your industry inexperience has prevented you from knowing their would be some very legitimate reasons why a company would not say this publicly.

author: EEVblog
author_rank: Unknown
timestamp: October 18, 2017, 10:28:23 pm
content: Quote from: _Wim_ on October 18, 2017, 06:20:25 pmAnd having had to have done this myself I can assure you the amount of work needed to convince a QA/Safety team within a large organisation to go with something "outside the banner spec numbers" is phenomenal.People didn't just wave their hands here, extensive testing and investigation would have gone into this.Those who have never done this would have no idea how much work is involved. I'd trust Keysight 100% on this.Also, ahugepart of this would be that this hasn't been an issue in at least 25-30 years they have been using this part in this way. Clearly it comes from the 34410A days and as John said, they have shipped 25,000 of those a year and it's the industry standard. If there was an issue it would have been found by now. So for anyone to simply come along and point at the datasheet spec and say "gotcha" is clearly demonstrably wrong.

author: _Wim_
author_rank: Super Contributor
timestamp: October 19, 2017, 06:07:38 pm
content: Quote from: EEVblog on October 18, 2017, 10:28:23 pmBut try to explain that to your QA/Safety department!I can imagine the frustration of the engineering team when QA/Safety said they will go public, but are not involved in cleaning up the mess afterwards...

author: s8548a
author_rank: Regular Contributor
timestamp: November 04, 2017, 05:01:53 am
content: Quote from: plesa on April 02, 2017, 11:31:18 amHi,Can you/anyone please explain about the better alternatives available and on what model DMM's will they work for logging?I am looking to buy a DMM and searching for various models like K2000, Agilent34401a, Rigol or Solartron but it is very confusing.Thanks.

author: emax
author_rank: Contributor
timestamp: November 15, 2017, 12:16:18 pm
content: After all, the whole fuzz has apparently turned out to be a no-problem, nice.I am after a DMM and the 34465A is in my focus, but before I order, I would like to know whether this statement is still current (maybe I've overseen a dementi somewhere):Quote from: Keysight Technologies Rep on April 01, 2017, 04:55:30 pmAre there any official news about that?

author: HKJ
author_rank: Super Contributor
timestamp: November 15, 2017, 12:27:01 pm
content: Quote from: emax on November 15, 2017, 12:16:18 pmIn David's interview with Keysight it is explained that it was some misunderstanding/missing documentation that was the reason, not any fault in the meter.

author: HighVoltage
author_rank: Super Contributor
timestamp: November 15, 2017, 12:29:05 pm
content: Quote from: emax on November 15, 2017, 12:16:18 pmBased on what John Kenny said in the interview with Dave, there was no problem, so there was no need to make any changes.You should be totally alright, ordering a 34465A

author: emax
author_rank: Contributor
timestamp: November 15, 2017, 12:34:18 pm
content: Thank you all, didn't watch the interview.Will be my christmas gift - made by myself, though.

author: anotherlin
author_rank: Frequent Contributor
timestamp: December 29, 2017, 10:45:54 am
content: Just purchased a 34465A DMM.It's a very recent one, factory calibrated on Nov 7th.Serial starts with MY5750xxxx.I just can't find the app-note pdf from Keysight stating which serial numbers starting with, have the max allowable voltage issue.

author: Dr. Frank
author_rank: Super Contributor
timestamp: December 29, 2017, 11:13:36 am
content: This technical note has been withdrawn... if it ever existed.In my archive I only found the reduced specification (600V dc max.)There has never been an issue, in reality.Frank

author: anotherlin
author_rank: Frequent Contributor
timestamp: December 29, 2017, 06:22:21 pm
content: Quote from: Dr. Frank on December 29, 2017, 11:13:36 amI know well that it is a non issue.I just wanted to know if my device is one of the newer revision.

author: HighVoltage
author_rank: Super Contributor
timestamp: December 29, 2017, 06:27:38 pm
content: You probably have to contact Keysight and ask them to be sure.(Most likely they will not let us know)Or open your 34465A DMM and look if the PCB has a new revision number.

author: anotherlin
author_rank: Frequent Contributor
timestamp: December 29, 2017, 07:40:18 pm
content: Ok, I've found it again:http://literature.cdn.keysight.com/litweb/pdf/34461A-04.pdfSo with a serial number starting with MY57xxxxxx, I have one of the new revised model.Note in question 5 (Q5 page 3), the devices having the max allowable voltage "issue" are offered an extra year of warranty (for a total of 4 years).

author: wraper
author_rank: Unknown
timestamp: December 29, 2017, 07:43:44 pm
content: Quote from: anotherlin on December 29, 2017, 07:40:18 pmI don't think that revised model was ever made. There was no issue to begin with, that was false alarm. Multimeters with later serial numbers had stickers over voltage ratings with reduced ratings. Later there was another service note which showed how to remove those stickers.From that service noteQuote

author: anotherlin
author_rank: Frequent Contributor
timestamp: December 29, 2017, 10:44:55 pm
content: Quote from: wraper on December 29, 2017, 07:43:44 pmThe "enhanced" or "revised" model may just be one with the "offending" part swapped with one with appropriate ratings.Or indeed, just the same, as it is claimed (by Keysight) to be a non-issue. Or maybe, they've taken the opportunity to make some other unrelated changes.I just wanted to know out of curiosity.