EEVblog #372 - Fluke 27 Multimeter Review & Teardown

[Excavatoree]

More info on the fuse resistor that can cause flickering on the ohms setting:  (I checked the one I have, and I see I've changed it.)

The V-ohms input jack has two resistors connected to it.  One is a ceramic film resistor on newer meters, and a carbon resistor on older meters.  (outboard)   Just inboard is a 1K fuseable resistor.  Since one end is connected to the jack, it's isolated, so you can check it without disconnecting anything.   

EDIT:  Whoops - seems the new ones have a 3.5 K.   (Same part as 87) The changeover was probably at the same time as the ceramic film resistor change for the "outboard" resistor. 

[retiredcaps]

Is it flickering or just the segments which are faded ?

Flickering.  No segments are faded.

[Polossatik]

just fyi: the 70 series claim "Alkaline:     ~2000 hours typical" 9V battery life http://www.fluke.com/fluke/usen/digital-multimeters/fluke-73-77.htm?PID=56121

[retiredcaps]

The V-ohms input jack has two resistors connected to it.  One is a ceramic film resistor on newer meters, and a carbon resistor on older meters.  (outboard)   Just inboard is a 1K fuseable resistor.  Since one end is connected to the jack, it's isolated, so you can check it without disconnecting anything.   

Thanks for checking and your suggestions.

I have two resistors connected to the volts/ohm input jack.  One is the 1K fuseable resistor and it measures exactly 1K.  I have a 220K ohm 10% (red, red, yellow, silver) resistor on the same input jack it and measures 232.4K ohms.

I'll see if I can get reliable readings of the movs without removing them or the shield.

[retiredcaps]

just fyi: the 70 series claim "Alkaline:     ~2000 hours typical" 9V battery life http://www.fluke.com/fluke/usen/digital-multimeters/fluke-73-77.htm?PID=56121

After giving my Fluke 77 II an IPA bath, I decided to measure its current consumption.

AC - 305 ua
DC - 280 ua
300mv - 270 ua
ohms - 275 ua
diode - 280 ua
A AC - 305 ua
A DC - 275 ua

[retiredcaps]

If the LCD only flickers in the ohms range, check the MOVs and the protection resistor.

I can only measure 4 out of the 5 without disassembly.  All 4 read 0L "in circuit" on the resistance scale on my Fluke 177.  For the 5th, I will have to disassemble.

[Excavatoree]

The MOVs are probably OK. 

Dave's video reminded me - check the thermistor or sometimes called a PTC.  It's in series with the 1K resistor and while I haven't seen a bad on in a 27, I've seen a bad one in an 87. 

It also looks like the 3.5 K resistor in the newer meters isn't fusable, like the older 1 K resistors were. 

[kodai]

Dave neglected to show the full range of the tilting bale.  It has two positions.  The first is the primary position and that is the one he showed in the video.  The second one is used to hang the meter up with.  When you lift the bale up about an inch, you can pull the two prongs out of their original sockets and then place them in the second set of sockets below.  There are guide slots on the bale's hinges that then guide the bale all the way up so you can then hang the meter off something.  Great little extra design thought by Fluke. 

I have two of the military 27/FM's (both are true RMS versions) and I love them.  I keep one in my truck just in case (or maybe just because).  I got one for $17.00 and the other for $21.00.  The cheaper one has all the serial numbers hand painted with some sort of white paint on all sides of the meter and the 6kV probe.  I have yet to find something that can remove it.  The other meter looks brand new, and so does the hard shell case.  My guess is it sat unissued in a storage closet for 22 years.  Both came with hard shell cases, 6kV probe, old PVC meter probes and aligator clips.  The best part is they both came with the fluke manual's for the meter and the 6kV and their U.S. Army manuals as well.  The army manuals are some of the best "how to" guides of a multimeter I've ever seen.  And of course they state that they should be destroyed to prevent their info from getting out, lol.

Besides the True RMS feature of the military models, the only thing I've noticed with the civy version is the fuses are different.  The military version uses 600mA and 15A fuses.  Oh, and the military version does not have a cap cover for the fuses.  If you guys start hitting ebay for some fluke 27's (any version) then be aware that in the U.S. ebay, they are starting to creep back up in price now.  The huge stockpile that came out a year ot two ago has pretty much bottomed out and its starting to show.  Also, its not uncommon for a seller to not check the fuses on these babies.  They assume that since the meter comes on, all is good.  So check both fuses as soon as you get it and budget in some extra cash for get some replacement fuses.  These are not the $5.00 HRC fuses (and yes, you can find them at that price if you look hard enough) like in the 87 series.  On average, these can be found on sale for about $15 from thrid parties, and $30 from fluke.  Just thought I'd give a heads up on hidden costs that some may not be aware of. 

All in all, I do love these bricks.  And thats what they are.  They are about the same size, shape, and weight of a good old fashioned brick.  Just about as tuff as a brick to boot.  Well worth having a couple of these puppies at the bench.  ^_^ 

[retiredcaps]

The MOVs are probably OK. 

Dave's video reminded me - check the thermistor or sometimes called a PTC.  It's in series with the 1K resistor and while I haven't seen a bad on in a 27, I've seen a bad one in an 87. 

It also looks like the 3.5 K resistor in the newer meters isn't fusable, like the older 1 K resistors were.

The 5th MOV measures 0L just like the first 4.  Here is a picture of my board.  It is different from Dave's.

[retiredcaps]

The guy I bought from had several in stock at $40 But It Now.

Someone didn't pay attention to the last bits of your video. $300 USD via best offer (asking price was $450 USD) for an used one sold yesterday.

http://www.ebay.com/itm/251047437015

[Rick]

The guy I bought from had several in stock at $40 But It Now.

Someone didn't pay attention to the last bits of your video. $300 USD via best offer (asking price was $450 USD) for an used one sold yesterday.

http://www.ebay.com/itm/251047437015

He must be a rich Arab sheikh I suppose...

[Rick]

The right hand one in the second pic is obviously an older model.

The one on the right looks like it has 0L "slanted" whereas the one of the left is "upright".  I have a Fluke 27 (grey/charcoal) and it has the "slanted" 0L.

I also notice that when it is set to resistance, the 0L looks like it is flickering as described in this thread

http://www.flukecommunity.com/forums/showthread.php?t=3458

I tried to respond, but I have been in the moderator's approval queue for 4 months now.

You were right... one of the LCD's is flickering on the ohm's range when "0L" is displayed on screen but not when it actualy measures something and that LCD has some faded segments (which I think can be fixed by doing some cleaning). He told me they were both fine... I got screwed.  But they both measure ok. I shall complain for that one...

+ Besides that it does have a few faded segments too.

[Rick]

I have the impression that it flickers whenever it displays "0L" not just on the ohm's range. I need to double check though.
--------
+ I have just checked. It flickers on the mV range too when "0L" is displayed on the screen, on the diode range it is also present, although it is more difficult to notice . Any idea about what could cause that?

[Rick]

I have cleaned the PCB contacts and the elastomer with alcohol, the flickering is gone and the faded segments too.
Sorry for the poor images taken by my gsm phone (before and after cleaning).

[Marvin]

I found these pics of the REAL 27/FM from here http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=167123

One can clearly see the RMS chip (in the middle of the board) there and other minor differences - seems that the PTC/thermistor (bottom left corner) protection was a late life addition/modification to the model as it is missing on the 27/FM. Or is it in different form factor and marked with a green and blue stripe?

[Branqazwsx]

I've got a fluke 27 with a few of screws missing out of the bottom. The one is from the main body with partial threads and the others are from the battery compartment. The rubber grommet is also missing from the main body screw hole. Any ideas of where I could pick up some more screws and a rubber grommet that would fit. I have attached some images.

Thanks

[mzacharias]

Regarding the slow continuity test on Dave's 27. I'm almost certain my old grey 27FM had an instantaneous continuity test. Can anyone confirm this? Don't have that meter anymore. I can say my 27II is instantaneous.

I do feel the low volume of the continuity and warning tone on my 27II is a concern, especially in an industrial environment. I assume it's because the rather smallish piezo buzzer is so well enclosed within the IP67 case.

Kudos to Agilent for flashing the back-light on the 1272A when it alarms and for making the beeper LOUD.

[Rick]

The 27FM (full grey, TRMS version) is identical to the 27 as far as the continuity test is concerned. I have two 27's and one 27FM. That is, it is as slow as the 27. My "newer" Fluke 27 is slower than the older Fluke 27 version actually. I am not sure if it is a problem of that particular device.

[grenert]

My grey 27/FM (TRMS model) has slow continuity.  It's surprising, considering the speed of continuity testing on Fluke meters in general.

[tryptamin]

hello dear comunity members:-p

iam new here and comes from germany...
 i work in the last weeks to buy me a good quality multimeter,and looks all vids on ebay from george.
he is fantastic!!!!
he beware me to buy some crap for  big money.
i need the multimeter at normal house electrics and for my car.
so i thinks the fluke 27fm are the rigth and best one for me.

if here anyone,who can sell me one cheap?
the shipping prices from us to germany are on ebay scary:)
sometimes 3*more than the fluke.
and sorry for my bad english.
i hope here are anyone,which can help me andsend me an message.

maybe i can get from you a better model...

hope and wait for postings here...

And further george,you do a good work


Greetz andy from germany

[Robomeds]

How old is this line of multimeters?  I'm  asking because I scored an 8025B off ebay recently.  In decent enough shape and for $17 I won't complain.  Anyway, I've been wondering if anyone knows the history of this line of meters.  When did they come out?  Was the 8025 the first version followed by the 25/27?  Based on the few date codes I think I read mine appears to have been made in 1989.  That puts it as later than some of the 27's I've seen people show on line.  Did they make the two at the same time?

Also, I've got to say this thing is HUGE.  I think it seems so large in part because it doesn't have the holster like my other Flukes.  The front panel is packed full of buttons, just that big selector switch.  Well that and the thing is literally twice as think as the 73-3 without a case!  No question this is a solid meter that can also be used in self defense.

[retiredcaps]

Anyway, I've been wondering if anyone knows the history of this line of meters.

Excavatoree provides some info at

http://www.ebay.com/gds/fluke-meters-rugged-types-models-and-series/10000000158117668/g.html

[retiredcaps]

In decent enough shape and for $17 I won't complain.

One went for 99 cents (only 1 bid).

http://www.ebay.com/itm/281117079588

The "A" version started at 99 cents and didn't attract any bidders.

http://www.ebay.com/itm/271217535252

[EEVblog]

One went for 99 cents (only 1 bid).
http://www.ebay.com/itm/281117079588
The "A" version started at 99 cents and didn't attract any bidders.
http://www.ebay.com/itm/271217535252

Wow, cheap!

[Robomeds]

In decent enough shape and for $17 I won't complain.

One went for 99 cents (only 1 bid).

http://www.ebay.com/itm/281117079588

The "A" version started at 99 cents and didn't attract any bidders.

http://www.ebay.com/itm/271217535252

That's $.99 meter (plus $15 shipping) is the one I got.  Sorry I was thinking after shipping the price was $17, not $16 
In retrospect I wish I had bid on both of them.  The seller relisted the A model at $50 BIN.  I don't think he made money on mine...

BTW, thanks for the ebay link.  I read that as well as a Excavatoree's great post in this thread
https://www.eevblog.com/forum/chat/fluke-25-my-first-digital-multimeter/

I'm still not sure when these came out.  It sounds like they might have come out at the same time as the 27s and that might have been around 1987 but that is really a guess on my part.