Fluke 87V (2021) teardown - Page 1
Forum section: electronics / testgear

author: SerjP
author_rank: Contributor
timestamp: March 07, 2021, 02:13:23 pm
content: Good day, EEV bloggers!New member here. I'm a former EE but am currently writing "boring business software" as someone said well on this forum. So, already being an amateur, I felt that I needed a good new reliable tool.I read all these battles here on the forum, comparing one in a yellow holster to another in a red one. Yelow or red? Hmm... good question. And I'm already have one DMM in a red which is Uni-T UT71E. Which sometimes has glitches (smth. with selector contacts?), too loud beeper, fluctuating digits, terrible continuity mode, etc. So I decided to buy a more reliable one.The things I considered for new DMM is:long-term stability (as I believe I can't afford going to certification labs every xx years)reputation/brand (well I never had anything from the top echelon before)and perfect internal design (look at that 87v board and the number of elements - the simplicity is a key; "beautiful" as Dave likes to say)So finally I selected to buy the yellow one. It will be my only top grade DMM on the bench.I think the number of digits is not that important to me and can be distracting. While less crowded dial is a plus.The phrase on the Dave's blog I love the most is - "don't turn it on, take it apart!!!". Cool! This is exactly what I planned to do.Of course I checked if it works correctly before doing that. I have also compared and recorded the readings in all ranges with the Uni-T (I can share results). So that after assembly I can make sure that the readings are the same and that teardown does not affected the accuracy.Some teardown justification: I wanted to see the overall build quality, to check if shield is not bended (I've seen pictures on this forum) and to check the fuses brand.So, here are some photos of the internals for those who would like to check the revision number and to compare with previous versions.Bought it from the well-known German online store W****.MFG date: Sep2020

author: SerjP
author_rank: Contributor
timestamp: March 07, 2021, 02:13:59 pm
content: Printed circuit assembly

author: SerjP
author_rank: Contributor
timestamp: March 07, 2021, 02:22:15 pm
content: Mileage for knob is less than 100 cycles. And we already can see some tracks on the PCB.Also there is no grease on detent spring (see 3rd photo; those scratches on the case is not a grease, it's just a scratches).

author: Wytnucls
author_rank: Super Contributor
timestamp: March 07, 2021, 03:49:13 pm
content: First one I see with Littelfuse fuses instead of Bussmann.

author: SerjP
author_rank: Contributor
timestamp: March 07, 2021, 05:25:09 pm
content: Some comments and questions from me:Leads are TL175looks a little better than TL75Shield is not bendedwe are good hereO-ring on the input terminal assembly is missingdid you noticed that from photos? This was unexpected. At least for FlukeI've already contacted seller for that. They were as surprised as I was. And kindly provided solutions to resolve this issue. So I'm waiting for a new O-ring from them.Fuses brandI've always worked with fuses that cost ~10 cents. So can't complain here. BTW Bussmann costs $50 on Digikey while Littelfuse is $25 (crazy prices anyway, lol). This is where Fluke gets the cost down. Is Littelfuse as good as Buss?Lack of grease on the detent springDo we need any grease here at all? I've added some consistent grease of unknown quality. I suppose it is better than nothing. Is it ok? I'm not an expert on materials, so I have no idea if a grease of unknown quality/brand can damage/disintegrate plastic over time.PS: the unit cost me ~400€ what is $480 (sales). I checked tme.eu and the price is $685 (VAT incl.). Also I found that in some USA shops the unit is also on sales/discount for $400. So it looks like a worldwide discounts, not only here in Europe. I hope discounts have nothing to do with those quality aspects noticed above.

author: Per Hansson
author_rank: Unknown
timestamp: March 07, 2021, 07:18:16 pm
content: What is the 9v battery lead doing underneath the 11A fuse for the amps mode?If they thought that was a good routing idea why even bother with a fuse with a 11kA interrupt rating or whatever it is?

author: Arhigos
author_rank: Regular Contributor
timestamp: March 07, 2021, 11:14:55 pm
content: Quote from: Per Hansson on March 07, 2021, 07:18:16 pmwhat's wrong with battery lead?

author: J-R
author_rank: Super Contributor
timestamp: March 07, 2021, 11:28:34 pm
content: My 87V from late 2018 has the battery wires in the same setup. Contemplating the potential current paths, I am not seeing a cause for concern, though.

author: Arhigos
author_rank: Regular Contributor
timestamp: March 08, 2021, 12:47:49 am
content: Quote from: J-R on March 07, 2021, 11:28:34 pmAll of them had same design for battery cable, beginning from original 87 in early 90-s.I never heard about any problem with that part

author: EEVblog
author_rank: Unknown
timestamp: March 08, 2021, 01:11:45 am
content: Thanks for sharing.How old is the 87 line now?Introduced in the late 80's IIRC.

author: Monkeh
author_rank: Super Contributor
timestamp: March 08, 2021, 02:04:42 am
content: Quote from: Per Hansson on March 07, 2021, 07:18:16 pmBecause the battery leads are sleeved with silicone-impregnated fibreglass which will be rated to at least 1kV?

author: Wytnucls
author_rank: Super Contributor
timestamp: March 08, 2021, 09:32:24 am
content: Fuses brandI've always worked with fuses that cost ~10 cents. So can't complain here. BTW Bussmann costs $50 on Digikey while Littelfuse is $25 (crazy prices anyway, lol). This is where Fluke gets the cost down. Is Littelfuse as good as Buss?Littelfuse fuses are rated the same, but are somewhat cheaper.Unless things have changed dramatically recently, all new 87 V meters come with Bussmann fuses.Are you sure this meter hasn't been tampered with, before you bought it?A missing O-ring and suspicious fuses make me wonder.Contact Fluke Germany if you want to find out:Fluke Deutschland GmbHHeinrich-Pesch-Straße 9-11D-50739 KölnTel.: +49 0(69)2222 20210Fax: +49 0(69) 2222 20224Email: service.de@fluke.com

author: Fungus
author_rank: Super Contributor
timestamp: March 08, 2021, 10:02:08 am
content: Quote from: EEVblog on March 08, 2021, 01:11:45 amThere's been V revisions of it though, some of them were quite big changes.The real question is how old is the 87V now and why did they stop innovating it?

author: Wytnucls
author_rank: Super Contributor
timestamp: March 08, 2021, 10:10:15 am
content: What for? It does the job, is well respected in the industry and has a long history. Why would you want to jeopardize all of that for some elusive extra sales?

author: Fungus
author_rank: Super Contributor
timestamp: March 08, 2021, 10:15:07 am
content: Quote from: Wytnucls on March 08, 2021, 10:10:15 ama) It was innovated before. The meter got better and nothing bad happend.b) Can you really think ofnothingthat could improve it?eg. 9999 counts so you have the same number of digits on screen when you measure 5V and when you measure 7V?

author: Wytnucls
author_rank: Super Contributor
timestamp: March 08, 2021, 10:50:58 am
content: Not much changed over the years (1988 Fluke 87, 1998 Fluke 87 III), if you discount the 87/89 IV (1999) which was completely different:IP30VFD (low pass filter)TempHigher diode test voltageExtra capacitance rangeSlightly better accuracy with a 6,000 count instead of 4,000That's it!

author: Fungus
author_rank: Super Contributor
timestamp: March 08, 2021, 11:03:26 am
content: Quote from: Wytnucls on March 08, 2021, 10:50:58 amWhy did they stop? Dave's review of the 97V was in 2009!

author: Wytnucls
author_rank: Super Contributor
timestamp: March 08, 2021, 11:08:11 am
content: They have the 289, with all the bells and whistles already, since 2007. Call it Fluke 87 VI and be done with it!Industry doesn't like big changes. People need to be retrained, manuals to be rewritten, insurance policies modified, etc...Some companies still use Windows 3.1

author: Per Hansson
author_rank: Unknown
timestamp: March 08, 2021, 04:38:58 pm
content: Quote from: Monkeh on March 08, 2021, 02:04:42 amOk, I just assumed it would be bad design practice, as for example you often have wide PCB cutouts for preventing arc-over.But here we have a cable literally clamped in the fuse holder (refer to picture: "2.1 DSC03156_.jpg")I based this off my experience of fuse holders with those stupid series lamps that light up to tell you the fuse failed:When the manufacturer places them in high energy circuits the whole fuse holder catches fire and melts into a mess.But granted the wires are not covered in sleeving so I guess Fluke knows what they are doing, it just rubbed me the wrong way seeing that...

author: Monkeh
author_rank: Super Contributor
timestamp: March 08, 2021, 05:30:30 pm
content: Quote from: Per Hansson on March 08, 2021, 04:38:58 pmWell, I'm no subject expert, but I'm not particularly concerned about an insulated assembly rated to >1kV in the presence of <1kV.

author: SerjP
author_rank: Contributor
timestamp: March 08, 2021, 05:35:07 pm
content: Quote from: EEVblog on March 08, 2021, 01:11:45 amMy pleasure Dave.I have more hi-res photos, can share if anyone is interested. Did not uploaded them due to forum limitations.Quote from: Wytnucls on March 08, 2021, 09:32:24 amThank you @Wytnucls. Dropped them a message.I suppose meter hasn't tampered. When I removed the screws I noticed the force it takes to unscrew them. When the item is new and was never disassembled it usually require a good amount of torque to remove the screws from ABS plastic. So based on my previous experience I'm pretty sure unit was not unscrewed before. Accordingly for the second, third times it usually so much easier to remove the screws. But yearh.. good point anyway, thanks.Quote from: Per Hansson on March 08, 2021, 04:38:58 pmI agree those sleeve underneath the fuse is that's smth. what you immediately pay attention to. Not the best design decision. Though while fuse is not blown the potential here on fuse holder clamps is about a couple of mV to the ground due to fuse extra low resistance. So no ways arc can arise here. The only way for arc to arise is to measure high voltage circuits (lets say more than 1kV) and high energy at the same time in order to blown the fuse (lets say more than 30A). Then yes that dangerous voltage would potentially trigger an arc to the battery leads. What voltage we need here to go through sleeve and through battery leads insulation? I guess more than 10kV. I've seen some test on youtube for that particular case (see below). BTW working with so high voltage/energy is out of scope for this meter, its even not a cat. IV I guess.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 08, 2021, 06:15:29 pm
content: Quote from: Wytnucls on March 08, 2021, 09:32:24 amWell, if W****** is a Fluke authorized distributor and the meter was purchased *new*, that possibility would be a very troublesome scenario.

author: Per Hansson
author_rank: Unknown
timestamp: March 08, 2021, 06:42:17 pm
content: Quote from: SerjP on March 08, 2021, 05:35:07 pmThank you very much for the linked video, it prooves well that I was wrongAnd thanks for your pictures

author: SerjP
author_rank: Contributor
timestamp: March 08, 2021, 06:52:07 pm
content: Quote from: SerjP on March 08, 2021, 05:35:07 pmIt seems I should take my words back. I just watched Dave's recent video about fuses. Couple of mV? no wayits may be even <spoiler>5V!</spoiler>But anyway it is too low, no chances for arc until fuse hasn't blown.PS: Also Dave said in that video the Littlefuse is a top brand and installed in Flukes. Hmmm.. Then I probably have to stop worrying about my fuses. But... I've only saw Buss in Fluke DMMs.Quote from: Per Hansson on March 08, 2021, 06:42:17 pmThank you. There is nothing wrong with your approach to check all possible scenarios when we are speaking about safety. It is better to prevent the accident by all possible means.

author: tooki
author_rank: Super Contributor
timestamp: March 08, 2021, 07:34:11 pm
content: Quote from: SerjP on March 07, 2021, 05:25:09 pmI wanna say that I’ve heard before that Fluke uses both Bussmann and Littelfuse, though Bussmann is clearly the more common one. They’re both top brands (together with Siba, another large, reputable maker of proper multimeter fuses). I see nothing suspicious about this at all.Note that the prices for those fuses (regardless of manufacturer) are always insane when bought under the fuse brand. You invariably pay FAR less for them when bought as Fluke items (which DK isn’t allowed to ship outside of USA, which is why they weren’t offered to you). At work, we recently stocked up on “Fluke” fuses from Conrad for around $6 each. (Bussmann is what arrived of course.)

author: tooki
author_rank: Super Contributor
timestamp: March 08, 2021, 07:43:25 pm
content: Quote from: SerjP on March 08, 2021, 05:35:07 pmThe cat ratings are for operator safety: it means the meter has been designed to be safe on circuits of a given type and voltage, by complying with requirements for transients. (E.g. CAT III 1000V and CAT IV 600V both require testing against 8000V transients.) By “safe”, we mean that no harm will come to the person using the meter.It does not mean the meter itself has to survive.Fluke’s entire reputation (and ability to charge high prices) is based on safety in industrial settings, so if they say a product is CAT III 1000V/CAT IV 600V, then it is, and they’ll have had this independently tested.As for Joe’s video, I want to say that there have been other reports of the same meter surviving similar tests. I think even Joe himself has said something to that effect. (If he’s listening, maybe he can fill us in, my memory on the issue is spotty.) Either way, the meter failing does NOT constitute a failure of the cat rating.

author: med6753
author_rank: Super Contributor
timestamp: March 09, 2021, 12:38:33 am
content: Quote from: EEVblog on March 08, 2021, 01:11:45 amI'm not sure when the 80 series was introduced. I bought my first generation 87 new in 1997 and to this day it's my first grab and go to DMM.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 09, 2021, 03:07:19 am
content: Quote from: EEVblog on March 08, 2021, 01:11:45 amIntroduced in Nov 1988 according to this thread that started 11 years ago by banned member Kiriakos-GR.https://www.eevblog.com/forum/testgear/i-need-to-know-the-history-of-fluke-87-(-1998-2010-)/msg3033264/#msg3033264

author: Wytnucls
author_rank: Super Contributor
timestamp: March 09, 2021, 08:10:59 am
content: Quote from: rsjsouza on March 08, 2021, 06:15:29 pmWe are official German distributor for Brymen, Maynuo and Siglent.45 days refund policyFluke is not mentioned. They sell from official distributors: 110 series/87V/287/289What happens to returned meters?One can buy spare fuses with the 87V purchase. (Cooper Bussmann Only!) (9.50 Euros each)From their site:

author: SerjP
author_rank: Contributor
timestamp: March 12, 2021, 06:41:12 pm
content: Quote from: SerjP on March 08, 2021, 05:35:07 pmGot the response from them:Code:Thank you for the information you provided us with regarding the missing o-ring.And for your question regarding the fuse brand, we received following feedback:“Littelfuse and Bussman are both manufacturers who have this type of fuse in their range and supply it to Fluke. There is no qualitative difference, both manufacturers are approved by us. So, everything is okay with the fuse”.Hope we could answer your question.

author: SerjP
author_rank: Contributor
timestamp: April 21, 2021, 11:34:23 am
content: After a couple of months playing email ping pong with the seller I'm still did not get neither the missing o-ring nor any compensation.The only thing I get from them is promises. Not so happy about it. While they were so kind at the beginning of email communication, unfortunately they don't keep their word on the issue resolution.What do you guys think is better to do now? I'm thinking of contacting Fluke representatives. But it looks like W**** where I bought my unit from is not the authorized Fluke distributor. It may means the limited lifetime warranty is not applicable for my case. Do you think it worth trying anyway?

author: rsjsouza
author_rank: Super Contributor
timestamp: April 21, 2021, 12:19:25 pm
content: Quote from: SerjP on April 21, 2021, 11:34:23 amWell, as one of my managers used to say:thenoyou already have. it doesn't hurt trying to go for ayes.

author: nicknails
author_rank: Regular Contributor
timestamp: April 21, 2021, 01:34:51 pm
content: In picture 3189, what are the 4 pads that have a sinusoidal space between them?

author: SerjP
author_rank: Contributor
timestamp: April 21, 2021, 04:00:50 pm
content: Quote from: rsjsouza on April 21, 2021, 12:19:25 pmwell said!Quote from: nicknails on April 21, 2021, 01:34:51 pmIt is just a push buttons contact pads. I think I also paid attention to them when I opened the meter for the first time. My first thought was maybe this is a printed capacitor of very small capacity or pads for some components which are missed.

author: joeqsmith
author_rank: Super Contributor
timestamp: April 22, 2021, 03:44:44 am
content: Quote from: tooki on March 08, 2021, 07:43:25 pmI am not sure what you want to know. In the video that was referenced, I show that section of the IEC standard and talk about the requirements. I would imagine any meter that has been certified would have had to pass that test. Of course, I mention I don't have a power supply that meets their criteria but if it broke down, we would know it.