Fluke 187 teardown photos

[bigsky]

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 - 2.4998V



1 count out - should be 5.0029V.



Spot on - 7.503V



1 count out - should be 10.006V.

[bigsky]

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.

[Muttley Snickers]

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

[bigsky]

Congratulations on getting a good unit and nice well documented thread.

Thanks.

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.

No problem.

I have other meters that I use with similar specs that can be replaced at the drop of a hat.

What do you use?

[Muttley Snickers]

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

[bigsky]

A member of the forum has done an immaculate job on preparing a specification list for meters over 6000 count.

Yes, seen it - very good.

What he didn't know was that it has become a shopping list for some of us disturbed equipment enthusiast's.

Having just been impressed by my new 187, I can see how buying DMMs can easily become an obsession. 

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.

Interesting - 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.

[bigsky]

I've measured the current draw of my 187.

Here are my values for reference:
Model                                    187             189
Power Off                          70.00ua       75.70ua
Power On Ohms Open     12.10ma      12.10ma
Back Light Low                   37.00ma      36.50ma
Back Light High                  73.50ma      71.00ma

Current draw tests were done with an Agilent U1272a   

Here are my figures:

Power off: 67.5ua
Power on ohms open 13.7ma
Backlight low 42ma
Backlight high 100ma

Measured 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?

[nukie]

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.

[bigsky]

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.

[Muttley Snickers]

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

[sags_v]

Can you take a picture without Input Jack Receptacle Module. Thank You.

[bigsky]

Can you take a picture without Input Jack Receptacle Module. Thank You.

Sorry, no, I'd have to unsolder it, which I don't want to do. I don't think there's anything under it.

[Ordinaryman1971]

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.

[bigsky]

Hi, the cal manual can be found at exodus.poly.edu/~kurt/manuals/manuals/Fluke/FLUKE 187_189_Calibration.pdf

I don't think I've ever seen a service manual or schematics.