Handheld meter robustness testing

[joeqsmith]

It's more than the color....   Notice the ratings and serial numbers. 

[joeqsmith]

Both "DESIGNED IN USA" but maybe they changed where they were made and corporate did not want to invest in having to re-certify them.           

[PedroDaGr8]

Both "DESIGNED IN USA" but maybe they changed where they were made and corporate did not want to invest in having to re-certify them.         

I think it's possibly because they changed the regulations and they didn't want to change their input v protection to recertify. That would be my guess.

Either way, that is VERY disappointing for Fluke to do.

[saturation]

Compare the PCBs side by side and check revision numbers.  IMHO, its likely they'll be identical.  Fluke likely dropped certification marks of other agencies to save money; a mark cost about $5,000-10,000 each per year per model in production. 

With IEC specifying standards and worldwide testing agencies harmonized to IEC, one agency mark is good as another effectively, but government entities may be slow to recognize other marks.

In North America, CSA is preferred over UL now, as it costs ~ 1/2 of UL.  Drop UL, no need for both.

VDE and TUV are redundant for the EU market, and can't hurt to put a free CE mark.  So drop at least one.

TUV is recognized in North America, so TUV and CSA are redundant but CSA may not be recognized in the EU.

The 'check ' mark is for AUS/NZ use.

Noticeably absent are marks for sale in PRChina, and Korea.

It's more than the color....   Notice the ratings and serial numbers. 

[joeqsmith]

If Fluke made a meter with the features and battery life of the BM869s, electrical robustness of the 107,  designed and made here in the USA and under 1K, I would be the first in line.   That's coming from someone who would never have owned another Fluke until I started trying to damage them.      Hard to believe Fluke would not mark them over money but then again, times change.

Here's the donated Greenlee.   Looks like there are a few positive reviews on it:

http://www.amazon.com/Greenlee-DM-20-Ranging-Digital-Multimeter/dp/B000FRQO6C/ref=sr_1_1?ie=UTF8&qid=1450227983&sr=8-1&keywords=greenlee+dm-20\

[PedroDaGr8]

If Fluke made a meter with the features and battery life of the BM869s, electrical robustness of the 107,  designed and made here in the USA and under 1K, I would be the first in line.   That's coming from someone who would never have owned another Fluke until I started trying to damage them.      Hard to believe Fluke would not mark them over money but then again, times change.

Here's the donated Greenlee.   Looks like there are a few positive reviews on it:

http://www.amazon.com/Greenlee-DM-20-Ranging-Digital-Multimeter/dp/B000FRQO6C/ref=sr_1_1?ie=UTF8&qid=1450227983&sr=8-1&keywords=greenlee+dm-20\

An interesting looking meter, whats the COO?

[joeqsmith]

An interesting looking meter, whats the COO?

Cost?  I have no idea.  Looks like the next higher up that replaced it is around $30.   I assume it's a rebranded.  Made in China, but looks like they could afford a UL listing. 

What's interesting is that the fuse is still good.   

Will have to test it with their leads.  Last time I tried that with a cheap meter, it did not work out so well for the meter.    Should be interesting.   

[PedroDaGr8]

An interesting looking meter, whats the COO?

Cost?  I have no idea.  Looks like the next higher up that replaced it is around $30.   I assume it's a rebranded.  Made in China, but looks like they could afford a UL listing. 

What's interesting is that the fuse is still good.   

Will have to test it with their leads.  Last time I tried that with a cheap meter, it did not work out so well for the meter.    Should be interesting.

COO = Country of Origin (which you answered).

I am intrigued to see a teardown and testing of this meter. It looks VERY different than anything out there. Kinda fat and chunky in a weird way.

[ModemHead]

Here's the donated Greenlee.   Looks like there are a few positive reviews on it:

2000 count manual ranging, with the lowest ACV range being 200V, means the basic design is the same as your average "830" cheapie with a 7106 COB, maybe an extra opamp for continuity tester.  Interesting, I see that Greenlee de-rated the high ACV range down to 300V, most cheapies are marked 500, 600 or even 750V.  And omitted the usual hFE test socket.  Did they beef up the input protection as well?

[joeqsmith]

COO = Country of Origin (which you answered).

I am intrigued to see a teardown and testing of this meter. It looks VERY different than anything out there. Kinda fat and chunky in a weird way.

I figured COO = Cost of Ownership.  In the end you had to spell it out anyway.   ROTFLMAO

2000 count manual ranging, with the lowest ACV range being 200V, means the basic design is the same as your average "830" cheapie with a 7106 COB, maybe an extra opamp for continuity tester.  Interesting, I see that Greenlee de-rated the high ACV range down to 300V, most cheapies are marked 500, 600 or even 750V.  And omitted the usual hFE test socket.  Did they beef up the input protection as well?

I looked at the manual last night.  Its available on Greenlee's site.  I saw that 300V max and laughed.   I like the 300 and 200 volt ranges.     I assume the 300 was originally marked at the higher level.   

My plan going forward is to follow the same sort of format as the last few videos I made.  So I will go ahead and remove the board so we can see what it looks like before.   Any bets on the input? 

[Fungus]

Here's the donated Greenlee.   Looks like there are a few positive reviews on it:

That thing looks horrible.  Awful screen. Range switch too small. Captive probes.   

I predict the insides will be terrible and it will fail on the barbecue-lighter test.

[saturation]

As a side story, I use DMMs often on metal hulled ships.  AC, even DC, is typically transient heavy enough to kill or severely injure DMMs, and I've experienced in use failures, but not explosions, with non-Fluke DMMs doing a typical measurement.  Fluke DMMs tend to dominate use on steel hulled vessels.  After Joe's test I've rerun some test myself and put the 101 seagoing conditions and its working very well, plus easier to pocket.  Equipment has to be very reliable if depended on and one is in the middle of the Pacific for stretches of time.  I've never seen side by side tests like Joe does here with different brands and models, and it clearly shows what you pay for. 

[Fungus]

As a side story, I use DMMs often on metal hulled ships.  AC, even DC, is typically transient heavy enough to kill or severely injure DMMs, and I've experienced in use failures, but not explosions, with non-Fluke DMMs doing a typical measurement.  Fluke DMMs tend to dominate use on steel hulled vessels.  After Joe's test I've rerun some test myself and put the 101 seagoing conditions and its working very well, plus easier to pocket.  Equipment has to be very reliable if depended on and one is in the middle of the Pacific for stretches of time.  I've never seen side by side tests like Joe does here with different brands and models, and it clearly shows what you pay for.

The Fluke 100 series seems quite unbeatable for reliable, safe, everyday usage (ie. non-EE work).

[saturation]

Yes, my 101 does 90% of what I need in the field.  The 10% is mostly modified sine wave converters that are way off on averaging meters then I have to macgyver the measurement.

Joe easily shows Fluke's secret sauce, they will scrimp on functions, but they don't on surge protection even for their cheapest cataloged DMM [ I think as of this writing, its the 101].

The Fluke 100 series seems quite unbeatable for reliable, safe, everyday usage (ie. non-EE work).

[Fungus]

Joe easily shows Fluke's secret sauce, they will scrimp on functions, but they don't on surge protection even for their cheapest cataloged DMM [ I think as of this writing, its the 101].

Yep. They're ideal for 'electrician' work. They're also only about $43 (delivery included!) so there's no excuse.

[joeqsmith]

As a side story, I use DMMs often on metal hulled ships.  AC, even DC, is typically transient heavy enough to kill or severely injure DMMs, and I've experienced in use failures, but not explosions, with non-Fluke DMMs doing a typical measurement. 

This is very interesting.  Could you provide more details about the cause of these transients and have you ever tried to characterize them? 

[saturation]

Yes!  Marine electricals need DMMs made for industrial settings.  Electric motors power cranes,lift, tools, equipment and the power inverters, alternators or generators supplying AC or DC are common culprits.  Modern ones start out fine, but they quickly deteriorate from the seaborn environment and start to pollute the surroundings fairly soon.  While the supplies are all isolated in ships noise can be coupled inductively to all the power wirings or radiated, and on older ships deteriorating insulation from accelerated wear from environmental exposure increase their noise potential: UV, hot sunlight mostly.  Common environmental killers are distant lightning strikes traveling on the top of the water column and heavy static from the environment, when in very dry air.  Radios, radar like systems have high pulse demands for power causing a lot of switching transients, if not RF noise in the general area.

Metal hulls act a bit like Faraday cages and help protect from noise, in practice its less that perfect and worst top side, and best when you're deep in the vessel.  Typical civilian vessels are fiberglass and offer less protection other than the conduits.

Note, ships are cleanest when at dock, most of the system could be shut off and many ships get AC from dockside connections, like an RV in a camp.  Its at sea when noise is greatest and need for reliability, highest.  Military ships with electronic warfare gear and carriers are even worse.

More details:

http://www.cedrat.com/fileadmin/user_upload/cedrat_groupe/Publications/Publications/2006/06/en51_Power_Quality_on_Electric_ships_PSCAD.pdf


The pdf is a brochure for a simulator of shipboard electrical system but it highlights the issues in more detail.

As a side story, I use DMMs often on metal hulled ships.  AC, even DC, is typically transient heavy enough to kill or severely injure DMMs, and I've experienced in use failures, but not explosions, with non-Fluke DMMs doing a typical measurement. 

This is very interesting.  Could you provide more details about the cause of these transients and have you ever tried to characterize them? 

[joeqsmith]

Just finished reading it.  Thanks.

[joeqsmith]

hi joeqsmith
can i suggest doing a sideshow, to try whipping the surges at some protection components with your gear, the aim is that by modding say the UNI-T with additional tested MOV or TVS, it then passes your surge test ?

Do you have a circuit in mind?  If so, post the schematic and I'll see what I can do.

[joeqsmith]

So there I was tonight playing with this Greenlee meter and I notice that it appears to has some sort of backlight for the yellow knob.   It only comes on every now and then and I can't find details about it in the manual..   

[joeqsmith]

no i dont have circuit in mind. its just an idea because the UNI-T PCB always come with unpopulated MOV. if say by putting in the MOV, and it can stand up to some more surge, it could be good news for some DIY-ers who are interested to mod it but do not know the result for a real surge.

There are a few things you should consider.....

There are many many different MOVs in the world.   I would doubt they put it right across the inputs for example.  So even if you knew the MFG and PN for the MOV, hooking it to the generator is not going to tell you much.   

Even if you traced out that part of the circuit of the meter you are wanting to test, clearances would not be the same if I just threw something together.  If your goal is to test a specific meter with some changes, I think to really know what is going to happen we would use the real meter.   

Next is your statement about "...DIY-ers who are interested to mod it but do not know the result for a real surge."
First, let's talk "real surge".   Let's just assume that the IEC standards represent a real surge.  I have been involved with these tests from time to time.  Believe me, if something goes wrong there it can be a real thrill.   Even my little half cycle line simulator does not come close to the amount of energy we test to.   And believe me, with all the comments people have talked about safety and how the meters have never been shown to be unsafe during my tests, the last thing you want is for someone who has no clue to modify their own meter and then think it would survive these tests or worse, somehow be safe.    None of us want that.   This is why there are real labs that run these tests.

Its fun to look at some of the mods people have done to their handheld meters.  Some of those rat nests would light up on a real test and worse, after cutting holes in the case, may actually come apart.   No thanks...

If the goal is to "harden" the meters front end, I tried to show how to make an attenuator for a meter.  Once again, people started talking about safety, which was never the goal.  It is a good way to protect the meters front end.  That may be a better approach. 

That said, believe me, I know what you are getting at and you are not the first person to ask me about this. My advice is just buy a better meter if you are concerned about it.

Here's the donated Greenlee.   Looks like there are a few positive reviews on it:

That thing looks horrible.  Awful screen. Range switch too small. Captive probes.   

I predict the insides will be terrible and it will fail on the barbecue-lighter test.

    You sir are a psychic!!!  I have finished my testing on the Greenlee and hope to have the video and updated spreadsheet in the next day or so.    Now about that backlight feature.....

[joeqsmith]

I was looking at a Newport HHM290 meter today.  What caught my eye was it measures inductance.  Then I noticed the two thermocouple inputs plus IR temperature.   Strange that they did not autorange everything.  It make the BM869s look small if that's even possible. 
 
http://www.newport.ca/Pdf/HHM290.pdf

For those who are interested in knowing how the Greenlee DM-20 held up during my tests, enjoy.

https://www.youtube.com/watch?v=SIQuk0E6wdU&feature=youtu.be

[PedroDaGr8]

I was looking at a Newport HHM290 meter today.  What caught my eye was it measures inductance.  Then I noticed the two thermocouple inputs plus IR temperature.   Strange that they did not autorange everything.  It make the BM869s look small if that's even possible. 
 
http://www.newport.ca/Pdf/HHM290.pdf

For those who are interested in knowing how the Greenlee DM-20 held up during my tests, enjoy.

https://www.youtube.com/watch?v=SIQuk0E6wdU&feature=youtu.be

Proved to be an interesting test.

SL is the circuit board manufacturer, according to UL the E234156 references "SHEN ZHEN SUN & LYNN CIRCUITS CO LTD". That would be your SL. Unfortunately, they are just the board maker, not the designer of the instrument. 94V-0 is a safety marking related to flammability (or lack thereof) if I remember correctly.

[joeqsmith]

Good info Pedro.   It's just a guess that it was re-branded. 

I was a bit surprised by the amount of sparks that came out of it.  I did not mention it during the video but I did check the leads after the last test and they were fine.  Held up better than the HF meter's leads.   

It would be good to know if the meter had a problem.  The continuity test threshold being so high and that the diode check did not work, I suspect there was a problem with the source.  The original owner told me he used used it for a volt meter only, so I doubt very much that these features are something that was ever used.   May have been bad from the factory.

The spreadsheet has been updated to include this meter.

[tautech]

Joe, after downloading your spreadsheet, it is not clear just what each of the cell pass/fails represent. 
Does it need a tweak or must we refer to your vids to understand what each test is?

Members often ask of DMM recommendations, must they watch all your vids?
Maybe a short further vid in the OP to just explain your methodology and spreadsheet results.

Can I also say it seems obvious (at least to me) that the thread title has many overlook the excellent work you have done, but maybe not so with the addition of DMM in the title. 

Tell me to F off if you must, it is YOUR thread.