Fluke 87V Robustness Tests, Part 4

[@lvxleather]

Your videos are great, been binging for the last few days. I will probably get your viewing hours up by a couple hundred here pretty soon lol.

[@joesmith-je3tq]

LOL. How you stay awake with that monotone voice of mine is beyond me.

[@derektodd4126]

Joe, as always. Great video, please keep up the good work and effort you put into your testing. DerekTodd, Northern Ireland.

[@joesmith-je3tq]

Thanks and I'm glad you are enjoying them.

[@1pcfred]

It lives!

[@joesmith-je3tq]

We are just warming up...

[@mastertronics95]

Joe Great Video. keep it up the good work . i have a question joe my fluke 87v does not have sn sticker on it . how to check the manufacturing year of my fluke without serial nos? thanks and more power

[@joesmith-je3tq]

Read this section: www.eevblog.com/forum/testgear/fluke-87v-pcb-revision-check-before-purchase/

[@DaruoshAghajaney]

Great as always. Thanks for the video. Looking forward to get the meter damaged :D Out of curiosity I opened my meter (feck the warranty) and the shield was bent.Yeah, poor craftsmanship. I bought my 87V in a heart beat after several months of saving. You're ruining my life : )))) I'm kinda disappointed with my choice, however it's always good to know the limits of a T&M device.

[@joesmith-je3tq]

Sorry to hear that about the shield. That's two that have looked and found this to be the case. I really don't get how this could happen. It seems to fit just fine. Fluke really doesn't make a good meter for electronics, IMO. If you were an electrical worker, they have you covered. There must not have been enough of a demand for meters like the 189. For me, the best meter they offer feature wise is the 289. The screen is too small, boots slow, graphing the way I would use it is pointless. I would rather have the faster less feature rich 189.

[@DaruoshAghajaney]

I have 2 fluke 289s and mainly use them for onsite data-logging. They are great, but suffering from high battery consumption and also poor outdoor visibility. Looking into market, i couldn't find anything close to them in terms of safety and reliability. UNI-T 181A will die with ONE hit of a grill starter (no modification of course) and there's another CEM with has a very poor build quality, and Bremen is not available in my country. either.

[@SeanBZA]

I would guess there was a batch made, and the same small crew doing the assembly, and they were either in a hurry, or were poorly trained, or were new crews on each batch, to make the same mistakes in assembly. I guess there was no tear down QC on the finished units, just a calibration and function test on the bare boards, then on the nearly fully assembled units, followed by a final exterior QC visual test and spot checking on all the ranges as final assembly before being packaged.

[@DaruoshAghajaney]

Well, I don't think only one or a few recently made batches have "bend gate" issue. Yesterday i convinced a friend of mine who bought his 87 V 4 years ago to take his meter apart and surprise!! The shield was bent. I cannot understand why or how they managed to bend the shield despite the straight design and assembly. I have many friends who have multiple 87Vs and i'm gonna check their meters too.

[@joesmith-je3tq]

Does seem that they have been building them with the shield bent for several years, rather than an isolated batch or group of people in a hurry. As I mentioned during the video, the first person who contacted me about it had a few years older 87V and theirs was also bent.

[@cannesahs]

Manual says for all functions sharing resistance rangeswitch position and diode rangeswitch position: Measuring Resistance W Caution To avoid possible damage to the Meter or to the equipment under test, disconnect circuit power and discharge all high-voltage capacitors before measuring resistance. So, Joe, I suggest testing first just voltage inputs to see how high we can go in those before damage. We kind of know diode clamps will fail 1.5kV tests.

[@joesmith-je3tq]

I don't believe in special snowflake meters. When and at what level it fails, it fails. Of course, you are free to conduct your own tests any way you like.

[@malgailany]

I guess that the LCD/Keypad plastic is installed after the shield was installed, causing the plastic to push out the metal shield out.

[@joesmith-je3tq]

As I mentioned, there are no clearance problems. The screws that hold the shield in place actually thread into that plastic you mention. You could install the plastic first using the two screws that are separate and then install the shield.

[@andrewnambudripad762]

Mmm, I've got a bone to pick with your arc testing of the failed fuse. When you removed the HRC filler contents (presumably silica, but I couldn't find an MSDS from Littelfuse), with it you removed an important component -- the fused silica that formed when the fuse blew. Depending on how it blew, the more fused silica (which has a dielectric constant about 3.5 orders of magnitude lower than air, and 4 orders from silica) was formed, further changing the flow characteristics. Electrical conductivity properties gets real complicated when you arc. As plasma is formed, he air composition moves from your standard "mostly O2, N2 dimers" to things like NO2, O3, etc. In the plasma transition phase itself there are going to be weird phenomena occuring like double layer Deybe shielding. Then the absense of the silicia will be replaced with the ambient atmosphere of your lab.The humidity content of your air is going to change the K value. To further complicate things, ohms law only operates in a linear fashion within a window. (There's an interesting paper from '88 out there, describing how extremely dry or super-saturated air remain monotonic but develop an interesting curvature (dtic.mil/dtic/tr/fulltext/u2/a199599.pdf pages 15-18)). I ain't no fancy physicist but electrical arcing be some complicated hub-bub.

[@joesmith-je3tq]

I'm sure there is point in there some where but you never seem to get to it.

[@andrewnambudripad762]

You performed a completely useless test by emptying the fuse out. It's simulating a fault which would not exist. In the field you either have an intact fuse, or a blown one. If it's blown, there will be silicia (and presumably aggregate generated from the fault) inside the tube, acting as a resistive element through the amps front-end path. In effect, by emptying out the fuse and eliminating the fused silica aggregate, you're simulating a field-fault that's actually the exact opposite of what a user would experience . (This can easily be verified by measuring the electric permeability of the fuse in circuit and functional, the fuse blown however intact, and a fuse with all of the filler material removed.)

[@joesmith-je3tq]

You completely missed the whole point of this test.

[@joesmith-je3tq]

I posted your comments on the EEVBLOG site if you care to join in the discussion. www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/2550/

[@RobB_VK6ES]

Joe, Fluke make an intrinsically safe version of this meter with a even more unreasonable price point. Do you know of any differences in the meter or is all down to testing and certification?

[@joesmith-je3tq]

If you were working with explosive fumes, I doubt the price point would be a big deal. I don't have a need for such a rating and have not looked into it.

[@SeanBZA]

That sleeving is rated for 5kv, as it is also used in street lighting as insulation for the internal high voltage wiring to the socket of the lamp from the ignitor, and from the ballast to the ignitor. That applies 3-4 kV to the lamp to start it, and can have a very high voltage for a long time when the lamp is EOL and no longer starts or cycles, or has broken the arc tube and the internal safety shorting has not worked to short the ballast, or the lamp has been removed.

[@joesmith-je3tq]

I doubt very much that there is only one source for this sleeve and the quality is the same for all of them and that there is only one size and they all follow the same requirements. We also see where with some parts (like the rubber boot for example) have suffered quality problems. I have shown meters using similar sleeve material in other meters. In this case with it right next to the fuse, I wanted to run it up and verify the sleeving, creepage and clearances.

[@CliveChamberlain946]

The king of meters has survived! 87V fans can go home now (since they may not have the stomach to watch part5..). Depending on IP rating, that smoke may indeed be a feature for discovering oops moments, but not enough to smoke anyone's salami..

[@joesmith-je3tq]

I could fry a few 1M resistors if you like.

[@mikeadler434]

👍👍

[@DonDenaBrenna]

creeping up on its death!

[@joesmith-je3tq]

For sure. I plan to run it to failure.

[@bar10dr]

Sad that Fluke is dropping their quality, I will never understand why companies ruin their reputation for short term profit margin.

[@joesmith-je3tq]

Like any company, Danaher is there to make money. If the market has no need for quality instruments, why make them?