Fluke 187 teardown photos - Page 1
Forum section: electronics / testgear

author: bigsky
author_rank: Regular Contributor
timestamp: October 24, 2014, 03:23:34 pm
content: Hi,I've just got myself a used 187. Nice meter (apart from the battery life). A few questions:The continuity bleeper is a pulsed tone - is that normal?Is there any way of displaying the number of calibrations it's had? (like you can on an 87V)Is there any way of displaying the firmware revision? (like you can on an 87V)The calibration manual references some service software - can this do anything interesting or useful?Would people be interested in some internal pics? I can take a few more than free_electron did here:https://www.eevblog.com/forum/repair/fluke-189-teardown-repair/(that's not a criticism)Would people be interested in seeing it connected to my chinese voltage reference?

author: retiredcaps
author_rank: Super Contributor
timestamp: October 24, 2014, 10:16:22 pm
content: 1) Use Eneloops.2) Yes, beeper is a pulsed tone and normal.3) Calibration is closed case and I don't/haven't found a way to display the number of calibrations.4) To see firmware, I think you need FlukeView Form?? I don't think there is any keypress to display firmware.5) Pictures are always welcome.6) Yes, show pics of the 187 with your Chinese voltage reference just like your 87V post.

author: Muttley Snickers
author_rank: Unknown
timestamp: October 24, 2014, 11:25:11 pm
content: In addition to retiredcaps great advice,I have both a 187 & 189 and never worried about firmware versions, the speculation about these chewing batteries in my case is a load of bullshit, turn it on, find the fault, turn it off. Others may need a meter running all day on the bench, I don't, for me they are or field service work.You probably should check the current draw of the unit as other people did have issue's with the super cap.Remove the batteries for long term storage.Here are my values for reference:Model 187 189Power Off 70.00ua 75.70uaPower On Ohms Open 12.10ma 12.10maBack Light Low 37.00ma 36.50maBack Light High 73.50ma 71.00maCurrent draw tests were done with an Agilent U1272AFantastic meter, good choice, well done.Muttley

author: Svuppe
author_rank: Regular Contributor
timestamp: October 25, 2014, 09:22:06 am
content: No need to check the current draw. The 187 doesn't have a supercap, only 189.I've had my 187 for over a decade, and I've changed the batteries once or maybe twice in all that time.

author: biot
author_rank: Regular Contributor
timestamp: October 25, 2014, 10:47:31 am
content: Some pictures of my 187 here:http://sigrok.org/wiki/Fluke_187/189Got it cheap, but it was a little broken: the probe socket assembly (last picture in free_electron's teardown) is sort of badly designed, and a part had snapped off. Be gentle inserting probes, I guess.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 11:40:06 am
content: Here are some photos of my 187. The quality isn't wonderful as I only have an old Canon Powershot A560, and took them using natural light. If anyone needs more or better pics, let me know and I'll try to oblige.I am not going to repeat much of what free_electron said here -https://www.eevblog.com/forum/repair/fluke-189-teardown-repair/- so read this in conjunction that.I hope the way I've done this is OK - it's my first - notes are under the pictures. I don't have the meter with me and have written the comments based on the pics, but hopefully I haven't missed anything.PCB underside - this is what you see when you open the case. It's fixed to the front with two screws, one through the hole in the shielding cover, and the other to the left of the smaller fuse. The larger fuse has been replaced with an incorrect 15A one. Note the battery contact pads at top centre.Close up of fuse contacts - the red dots are adhesive. Note the fuse sizes are copper tracks, as are other designations - no silkscreening on this PCB. The larger fuse is given as 10A on the PCB but elsewhere as 11A.Under the cover is a custom chip for range switching, true-rms conversion, and ADC, plus the Analog Devices REF43 voltage reference. Note the guard tracks around the thick film voltage divider, also the way that the pins on the IC have been laid out in sequence - one of the benefits from designing your own ASICs.Upper part of the underside. The square grey part with a corner cut off is the bleeper. Pads for calibration switch to the right of it. To the left is an unpopulated footprint for the supercap which is used for memory retention on the 189 - it's notorious for leaking. Backlight connector at bottom left. I'm not sure what the unpopulated DIL pads at bottom right are for - they're not populated in the 189.EDIT- the part above it is a 93C55 serial EEPROM (calibration constants?) - but as the empty pads are parallelled horizontally I'm don't think they're for this in an alternative package. Perhaps they're for a 2 x 4 surface mount header for ICSP, JTAG, or something similar (although I would have thought a pin or two more would be needed).LT1307 DC-DC converter driving a transformer. It appears to generate three separate output rails based on the output diodes and caps. I think I read something saying that it can run the batteries down to above 1 volt each, which seems pretty good. The transformer is by Coiltronics, who appear now to be owned by Cooper Bussmann.IR tx / rx on the top edge.The CSB455J is a 455kHz ceramic resonator by Murata. Not sure what it's for - possibly the LCD - it seems to be connected to the LCD driver which is on the other side of the board. Note the red dots of adhesive, almost certainly applied with a syringe.I think that's enough for one post. I'll do the other side of the PCB in another post.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 12:05:01 pm
content: Next lot of pics:Top side of the PCB with the LCD assembly removed. The input socket assembly is very similar to the 87V, despite the different case design.LCD module underside showing zebra strips.Top-notch input protection as expected.10A current shunt and associated parts.Thick-film voltage divider with guard tracks.Top view showing guard tracks.Main ICs. The left one is probably the processor - could it be an MSP430? Note the empty footprint above it, presumably for the memory chip on a 189. The right chip looks like an LCD driver. The 12.5MHz crystal between them is by Fox Electronics.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 12:20:41 pm
content: Final lot of pictures for now. I'll take some ones with the voltage reference tomorrow.Rev 007 PCB. Is Kalex3 the project or PCB codename?Assembly rev 015 ?Blast shields on case rear fitting into isolation slots on PCB.Case front showing standard Fluke switch design. Note the screening and contact top centre. The slot between the switch and the buttons is where the voltage divider fits - a clever design touch.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 12:27:28 pm
content: That's all for now. Fire away with your comments! I've appreciated the replies to my questions on the forum and wanted to contribute something back - I wasn't able to find any photos of the insides of a 187, and only a few of the 189, so I'm pleased to provide them. I'll take some more pics with the voltage reference tomorrow.I am very impressed with the 187 - the construction is excellent (although I prefer a separate holster) and the accuracy, as you'll see, is superb. I wish Fluke would re-issue it using lower power parts.

author: krivx
author_rank: Frequent Contributor
timestamp: October 25, 2014, 01:15:18 pm
content: Are the images not showing for everyone else?

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 01:22:26 pm
content: Quote from: krivx on October 25, 2014, 01:15:18 pmSorry, it looks like I've messed up. The pics worked for me when I was logged in, but I logged out and they disappeared, even when I logged back in again. Is there any way of uploading images to the forum and them calling them up with an bbcode tag so I can put them in-line with the text?

author: krivx
author_rank: Frequent Contributor
timestamp: October 25, 2014, 01:24:24 pm
content: I think you can just attach multiple images and they are shown at the bottom of the post? If you want to refer to them using bbcode I guess you could use an external free image host, Imgur.com maybe?

author: SeanB
author_rank: Super Contributor
timestamp: October 25, 2014, 01:59:07 pm
content: Put as attachment to post ( or a few posts) then go back to the page and open it in another tab. Then edit it in that tab and use the image tag to drop in the URL ( weird one with the =image in it on each thumbnail) and save the lot again. then they all show up for all.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 02:18:13 pm
content: Quote from: SeanB on October 25, 2014, 01:59:07 pmThat's basically what I did - here's an example of the tags I used:Code:https://www.eevblog.com/forum/testgear/fluke-187/?action=dlattach;attach=114562;imageI think I shouldn't have unticked the files in the attachment list after I added them as links - I reckon that deleted them off the server. I didn't want all the thumbnails at the end of each post, but if that's the only way of doing it, then so be it. Please let me know what I should do.

author: SeanB
author_rank: Super Contributor
timestamp: October 25, 2014, 02:51:29 pm
content: Unticking does it, it removed the file off the server. Use a Flickr account, upload the pics and then grab the BBcode for them to insert direct.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 02:56:30 pm
content: Thanks, SeanB, I think I'll reupload them here and put up with the thumbnails - I see others have done the same. It means I don't have to worry about another account with an image host.

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 03:10:27 pm
content: I've redone the first lot of pictures - can someone confirm that they can see them, and then I'll redo the rest.

author: krivx
author_rank: Frequent Contributor
timestamp: October 25, 2014, 03:13:53 pm
content: Looking good

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 03:29:09 pm
content: OK, all sorted. If a moderator is reading this or someone can contact one, perhaps these last few posts about the broken images can be deleted as they don't really add anything to this thread.

author: KGB
author_rank: Contributor
timestamp: October 25, 2014, 07:18:22 pm
content: Quote from: bigsky on October 24, 2014, 03:23:34 pmHi.Have you tried this?:Push down the RANGE button and simultaneously turn the meter on, (my 189 says 2.02).And an interesting thing, animated display test:Push down the HOLD and the BLUE button and simultaneously turn the meter on and wait a bit, must be hold down the buttons.It may also work on the 187.Cheers.

author: retiredcaps
author_rank: Super Contributor
timestamp: October 25, 2014, 08:17:07 pm
content: Quote from: KGB on October 25, 2014, 07:18:22 pmI get 2.02 on my 187 as well. Thanks for sharing this tip.

author: retiredcaps
author_rank: Super Contributor
timestamp: October 25, 2014, 08:18:40 pm
content: Quote from: Muttley Snickers on October 24, 2014, 11:25:11 pmYes, good advice. My used 187 had corroded battery terminals from the previous owner due to leaking batteries.PS. Don't forget you can set the backlight timer and autopower off via menu settings to extend battery life.

author: retiredcaps
author_rank: Super Contributor
timestamp: October 25, 2014, 08:21:23 pm
content: Quote from: bigsky on October 25, 2014, 11:40:06 amExcellent photos and thanks for doing it.On the fuse photo above, it looks like there is some stray metal shavings from removing the fuse from the holder? If yes, I suggest you clean them out otherwise there is a small risk of shorting things out if they move into the more dense SMD section?Or is that dust?

author: miguelvp
author_rank: Super Contributor
timestamp: October 26, 2014, 03:44:07 am
content: Or grey beard dandruff

author: Muttley Snickers
author_rank: Unknown
timestamp: October 26, 2014, 04:21:53 am
content: Not sure what country he is in, But he might want tocheck that shit out with a geiger counter.Muttley

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 12:09:56 pm
content: I'm sure it's just dust on the PCB.My 187 reported version 2.02 when switched on with the range button pressed - again, thanks for the info.Here are some pics with the chinese voltage reference:Calibration values on the reference.Spot on - 2.4998V1 count out - should be 5.0029V.Spot on - 7.503V1 count out - should be 10.006V.

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 12:33:22 pm
content: Obviously the above readings were not made in controlled lab conditions, and we don't know how good the calibration values of the voltage reference are. But the fact that the meter differs from these by 1 count max is an encouraging sign. Also my 87V matched them as well.The date codes in my 187 are mostly 2006, so I reckon it is eight years old. There are a few marks on it, so it's definitely had some use in an industrial environment. And I bet it's never been calibrated or adjusted. The fact that it seems to be well within its tolerances is amazing. Wasn't one of John Fluke's principles that the customer should always get more than they paid for?All I can say is that Fluke certainly knew what they were doing when they designed the 187/9 - I'm seriously impressed by its accuracy.

author: Muttley Snickers
author_rank: Unknown
timestamp: October 26, 2014, 01:08:26 pm
content: Congratulations on getting a good unit and nice well documented thread.Sorry if I gave you a bum steer on the super cap, I was being lazy and didn't check either my facts nor my meters.Nowadays I rarely pull out the 187 and 189, it may sound stupid but I will probably never again see two of these meters in original boxes, all accessories, and both in immaculate condition with the protective film intact.I have other meters that I use with similar specs that can be replaced at the drop of a hat.Thank You for your efforts.Muttley

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 01:12:20 pm
content: Quote from: Muttley Snickers on October 26, 2014, 01:08:26 pmThanks.QuoteNo problem.QuoteWhat do you use?

author: Muttley Snickers
author_rank: Unknown
timestamp: October 26, 2014, 01:37:59 pm
content: Don't get me wrong, occasionally I will put them in the truck just in case, but more often than not they don't see day light.A member of the forum has done an immaculate job on preparing a specification list for meters over 6000 count.What he didn't know was that it has become a shopping list for some of us disturbed equipment enthusiast's.U1272A, UT70D, 179 and pretty much anything with min-max, depends on the job, for up ladders and on roofs a cheap meter that can bounce straight into a nearby bin is a good choice, large building sites are a bad place to leave a yellow meter lying idle so I would use a UT70D.Bench work, diagnostics and logging U1272A is the go.Muttley

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 02:02:15 pm
content: Quote from: Muttley Snickers on October 26, 2014, 01:37:59 pmYes, seen it - very good.QuoteHaving just been impressed by my new 187, I can see how buying DMMs can easily become an obsession.QuoteInteresting - I don't think any of those are as accurate as a 187, not that you'd need it for what you describe. And I don't need it either - I just got the 187 as I wanted something that could measure dBm directly. I paid about GBP 90 delivered for it.I wouldn't mind a U1272a, but can't justify it.

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 02:06:01 pm
content: I've measured the current draw of my 187.Quote from: Muttley Snickers on October 24, 2014, 11:25:11 pmHere are my figures:Power off: 67.5uaPower on ohms open 13.7maBacklight low 42maBacklight high 100maMeasured with an 87V.But the batteries in my 187 are somewhat used (about 1.3v/cell), so the dc-dc converter will be taking more current from them.Would people be interested if I was to do some basic investigations of the dc-dc converter in the 187/189?

author: nukie
author_rank: Frequent Contributor
timestamp: October 26, 2014, 10:32:38 pm
content: I have various UTxxx multimeter, the 187/9 is always ready to go my bench with several 34401 and keithley 2000. I reach for the flukes most of the time due to reliability and portability.I don't have a problem with the battery consumption. I think I have to recharge the Eneloops two to three times a year I don't remember but it's not regular. I leave mine in VDC or mV setting to reduce wear on the range switch and gold plated copper tracks, let the Auto-off do it's job.

author: bigsky
author_rank: Regular Contributor
timestamp: October 26, 2014, 11:01:06 pm
content: PM sent, thanks.I think my 87V will still be my first choice, as it's a bit smaller, but the 187 will make a good second meter.

author: Muttley Snickers
author_rank: Unknown
timestamp: October 26, 2014, 11:05:58 pm
content: To bigsky.My current draw tests were done with a linear power supply at 6.0 volt with the U1272A.I mentioned that I used other meters with similar specs, in retrospect I should have said features in the context of handheld DMM's.The UT70Ds are in my opinion run of the mill meters, I got 3 plus a UT81B from a supplier clearance for $320.00 all later versions, ok for general stuff.You asked me what I use, any meter at hand is the answer, what I recommend is irrelevant as each tech has their own requirements and there are better suited people here than me to answer what is the best.Ask someone else and the name Gossen may be mentioned.And just to finish as I am now starting to drift off topic, I my case there are meters that I wanted (eg: 179-187-189-U1272A ) and then meters that I came across, generally by fluke. ( Pardon the pun )Muttley

author: sags_v
author_rank: Newbie
timestamp: January 27, 2016, 09:34:09 am
content: Can you take a picture without Input Jack Receptacle Module. Thank You.

author: bigsky
author_rank: Regular Contributor
timestamp: January 27, 2016, 09:41:19 am
content: Quote from: sags_v on January 27, 2016, 09:34:09 amSorry, no, I'd have to unsolder it, which I don't want to do. I don't think there's anything under it.

author: Ordinaryman1971
author_rank: Frequent Contributor
timestamp: October 17, 2016, 02:29:42 pm
content: Hi everyone,I know it's an old post but I wanted to ask if there is anybody out there that has service manual for 189 or 187 and the calibration manual.Please post them or maybe you know the link to some web side that has one of those, it would be appreciated.

author: bigsky
author_rank: Regular Contributor
timestamp: October 17, 2016, 02:36:12 pm
content: Hi, the cal manual can be found atexodus.poly.edu/~kurt/manuals/manuals/Fluke/FLUKE 187_189_Calibration.pdfI don't think I've ever seen a service manual or schematics.