Handheld meter robustness testing

[Fungus]

Well, when you get reviewers of test gear (including Dave) spending time ranting about how "cheap" or "toyish" an equipment looks, you end up amplifying the feel that a teat gear has to also score high on this criteria

These days a student can knock out a dozen CAD renderings before lunch so there's no real reason why it has to score low, not at any price point.

[joeqsmith]

Just to make it perfectly clear,  with the rubber case on, I can toggle the relay/s with the included Extech magnetic strap I showed in the last video with no problems.  Also, if that strap were installed on this meter it can easily reach that area of the meter.   

And because someone asked, I did remove the batteries in an attempt to reset the meter as well.  As expected, a bust.

2N3055,  obviously I agree about the cost of the magnetic strap.  I think the cost of the software and cable were $450.

And Keysight, Gossen, Fluke and all bigo ones.... none of them are sacred cows... I don't necessarily agree with every test Joe does, or even his conclusions sometimes.. But I love his irreverence and lack of idolatry.... Premium manufacturers are not faultless, and us being critical to them, instead running sorts of cults that worship certain brands, is good.
It is good to us (better products for us) , it is good for them ( we keep them honest ) in a long run.... And it is even better for second tier manufacturers and us.. It makes them try harder...And give us better affordable products...

I agree that no brands are sacred.  If I found something I liked better than the Brymen, I would own it and talk about it.  The testing being what it is, is bound to cause people to interpret the results differently or not agree on the test methods in general.  It's new territory.  If it were common practice, I would not be doing it.   I am fine with that.   It's your next statement that comes as a bit of a pleasant surprise.  I get called out a fair amount for being biased toward one brand or another.  It's refreshing when someone sees it otherwise. Thanks. 

I do not want to defend Joe's "crusade" on the Gossen meter ( I think he does a bit of drama on purpose.. It's how you stir up the people ), but I agree with him on general principle :
If I pay for a handheld as much as for a good 6.5 Digit Benchtop meter, I want it to be better, more robust and superior in every TECHNICAL aspect to a Brymen or whatever else out there.. I want it to have Mu metal shield, 2ppm/C stable reference, etc, etc...  It has to an overkill on specs..
Otherwise why on earth would I buy it... If it's not actually better?
 
For the price you can buy FLUKE 87V AND Brymen 869S ... Or Brymen 869S AND FLUKE 289 ...  And all three of those are very good... And will do the task of measuring at least as good...

My 2c and million words... Sorry for verbosity..

Perhaps ego?  Maybe just to see how it was designed and constructed or how robust it is?  Maybe you started a poll and it was voted on?   

[joeqsmith]

P.S. Should I mention Japan and motorbikes 
3DB

Just bikes in general are always a good topic.  The faster / quicker, the better!

[P90]

P.S. Should I mention Japan and motorbikes 
3DB

Just bikes in general are always a good topic.  The faster / quicker, the better!

Around these parts we call motorcycle riders "organ donors."
I'd rather take my chances poking around in a 480V 3ph panel with a DT830 multimeter... 

[Wytnucls]

They only work with the rubber boot on and may not be as strong as the one you played with.
If there is a magnetic interaction with the holder, then I'll agree that Gossen should at least warn their customers.

The Fluke 185 relay is also affected by a strong neodymium magnet held to the back of the meter, but only if taken out of its boot.
The 8 pound magnet at the tip of my magnetic wand had no effect.
The Fluke 867B case is so big, only the LHC may affect it in any way.

https://www.amazon.com/Magnetic-Telescoping-Retriever-Telescopic-Retrieving/dp/B0175B3VRU

When you remove the magnet and power off the meter.What happens when you power it on ?

3DB

Without any input, I can change the auto ranging from mV to V and vice versa at will, by reversing the polarity of the magnet.
On restart, the auto ranging click back to the correct mV range.
With mains connected, the relay clicks back to the correct range too.
With mains connected, auto ranging can be changed with the magnet from 500V to 1000V, which then shows an erroneous OL.

I couldn't find a scenario where the meter would display a low voltage with mains connected.
I've been using very strong double stacked cylindrical neodymium magnets.

So the Fluke seems reasonably safe.

Morale of the story: Don't use a magnetic holder if your meter is equipped with relays. Doh!

[Wytnucls]

Gossen is well aware of the interaction, warns about it and lists the meters affected:

https://www.gossenmetrawatt.com/resources/tt/hitclip/hit-clip-ia_dgb.pdf

[Fungus]

Gossen is well aware of the interaction, warns about it and lists the meters affected:

That says "during operation".

There's no mention of transport or that it can get stuck in a "wrong" state which isn't cleared at power-on.

[Wytnucls]

Hard to think Gossen wouldn't have checked the meter for that eventuality.
If it does happen with their holder too, and all indications are that it may, they should advise customers to keep magnets away from the meter until they update the software, to make sure the relay is on the right connection at power up.

[3db]

P.S. Should I mention Japan and motorbikes 
3DB

Just bikes in general are always a good topic.  The faster / quicker, the better!

 

Around these parts we call motorcycle riders "organ donors."
I'd rather take my chances poking around in a 480V 3ph panel with a DT830 multimeter...

My point is that Japan started from nothing and became a MAJOR player in the Motorbike and car industry.
The established companies were complacent and didn't see this until it was to late.

 

[joeqsmith]

Hard to think Gossen wouldn't have checked the meter for that eventuality.
If it does happen with their holder too, and all indications are that it may, they should advise customers to keep magnets away from the meter until they update the software, to make sure the relay is on the right connection at power up.

All I need to do is pull the meter away from what ever it is strapped to, have that strap bounce around while I move the meter to the new location and not power cycle the meter.  There is no way I can see something as simple as pulsing the relays on start up as being a solution.  It may be just a quick to use the ohms mode to reset versus a power cycle each time the meter was setup.  IMO, if you are going to use them, they better gave feedback or shielding to prevent it.  Even with feedback, if the meter could be in an unsafe condition from switching there is no way I would allow for it.  By the time the meter detected the fault and corrected for it, the damage may already have been done. 

IMO, the standards should account for this.  That's a very large body and I get the feeling moves very slow.   And the fact you claim Gossen is 100ish years old with all this experience makes it worse.  They should know better.  There is no excuse on their part for releasing a design like this into the public. 

If you would rather a nice fluffy review, Dave's on the  Energy is pretty good.  Gossen provides a link to it from their website.  You are not going to see them linking my review any time soon. 

[joeqsmith]

My point is that Japan started from nothing and became a MAJOR player in the Motorbike and car industry.
The established companies were complacent and didn't see this until it was to late.
 

And they continue to make them quicker and faster!!      Most of what I see on the road now are HDs.  Never underestimate the power of good marketing and the human ego vs technology.

[Fungus]

It may be just a quick to use the ohms mode to reset versus a power cycle each time the meter was setup.

One of those is unsellable. People would laugh at you if you told them to switch to Ohms mode before every reading.

The 'solution' is magnetic shielding and pulse the relay whenever you select a range that depends on it.


PS: Google tells me they manufacture magnetically shielded relays with metal cases especially for applications like this. So much for Gossen's "100 years of experience". 

[joeqsmith]

It may be just a quick to use the ohms mode to reset versus a power cycle each time the meter was setup.

One of those is unsellable. People would laugh at you if you told them to switch to Ohms mode before every reading.

The 'solution' is magnetic shielding and pulse the relay whenever you select a range that depends on it.


PS: Google tells me they manufacture magnetically shielded relays with metal cases especially for applications like this. So much for Gossen's "100 years of experience". 

People would laugh if I told them they had to power cycle the meter between readings as well.   Of course if people knew what a POS the meter is for the $850 they spent on it, they would not be laughing anymore. 

Again, if you are in the middle of using the meter and it changes states, if this makes a hazardous condition I would say pulsing before hand does not solve it.  Don't address the symptom, go for the root problem.   

[Fungus]

Have you tried whacking it yet?

[joeqsmith]

Have you tried whacking it yet?

Whacking is not very scientific.  Maybe someone here has a vibration table and would make up a test jig for one.  Anyone who has done this sort of work knows the problems.  It's not something the datasheets are going to tell you. 

There is a lot more testing to be done before I would consider some sort of mechanical shock test and that Extech strap should be enough to raise a concern. 

[Fungus]

Have you tried whacking it yet?

Whacking is not very scientific.

Exactly what I predicted you'd say (on the previous page).

It's fun though, and might give you an idea of how easy/difficult it is. 

I'd give it a few sharp taps with a little hammer from all six sides.

(yeah, normally it would have rubber if it was transported a lot, but this is an 'informal' test)

[joeqsmith]

Have you tried whacking it yet?

Whacking is not very scientific.

Exactly what I predicted you'd say (on the previous page).

It's fun though, and might give you an idea of how easy/difficult it is. 

One problem: He likes to quantify things and "slapping" is unscientific. I can't wait to see the machine he invents for this. 

I wonder how my wife would feel about setting up small environmental chamber with a vibration table in the living room. 

[joeqsmith]

Looks like the low end company is stepping up and doing the right thing with a recall over a similar problem as this Gossen.   Gossen's technique is just ignore it's customers.  Really sad. 

https://www.cpsc.gov/Recalls/2017/extech-recalls-digital-clamp-meters

[gslick]

Looks like the low end company is stepping up and doing the right thing with a recall over a similar problem as this Gossen.   Gossen's technique is just ignore it's customers.  Really sad. 

https://www.cpsc.gov/Recalls/2017/extech-recalls-digital-clamp-meters

http://www.extech.com/display/?id=16536

This recall stems from consumer reports that the clamp meter’s input terminal screws are loosening. The loosened screws can create an open circuit at the test lead input jack of the meter, causing the meters to give inaccurate voltage readings. An incorrect reading can cause the user to falsely believe that the electrical power of the test subject is low or off, in turn, posing an electrocution hazard.

[joeqsmith]

http://incompliancemag.com/extech-recalls-digital-clamp-meters/?utm_campaign=Weekly%20Recall%20Alert&utm_source=hs_email&utm_medium=email&utm_content=52443488&_hsenc=p2ANqtz-_V2Rd_O2RVii4mNlz7ZkIy4dQLx8y6795z8tHXlzsto-qNahTXzZOOTQInsy-QVAnS-v-iquHlNVee6rSKZPX5Mnisbw&_hsmi=52443488

[joeqsmith]

I guess if someone dies or gets injured, then you notify  https://www.saferproducts.gov/     

[jordanp123]

Have you every heard anything from Gossen? For the price of this meter you would think customer support would be top notch.

[joeqsmith]

Have you every heard anything from Gossen? For the price of this meter you would think customer support would be top notch.

They have not. Maybe they forward all US emails to Dranetz.   They may still have my email blocked after I asked them about alignment. 

[Fungus]

One problem: He likes to quantify things and "slapping" is unscientific. I can't wait to see the machine he invents for this. 

I wonder how my wife would feel about setting up small environmental chamber with a vibration table in the living room. 

A vibration table lets you accurately compare meters against other meters but it doesn't give you any feel for how easy it is to do the real world. For that you need to slap it around a bit.

[P90]

One problem: He likes to quantify things and "slapping" is unscientific. I can't wait to see the machine he invents for this. 

I wonder how my wife would feel about setting up small environmental chamber with a vibration table in the living room. 

A vibration table lets you accurately compare meters against other models but it doesn't give you any feel for how easy it is to do the real world. For that you need to slap it around a bit.

throw 'em in the dryer machine...