Author Topic: EEVblog #1007 - Is a $25 Multimeter Any Good  (Read 94610 times)

0 Members and 1 Guest are viewing this topic.

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2105
  • Country: au
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #125 on: July 16, 2017, 08:50:49 pm »
There is no reason to buy, or, even worse, to use this meter.
It is lying about its safety specs --> getting immediatly disqualified.
End of story.


It's also not a cheap meter once you open up and re-solder and check all those solder starved joints,
what's ONE hour of your tech time worth?  assuming all the 'price point selected' components can survive another high temperature ordeal

I would not trust those ridiculous midget fuses to blow when required,
or even assume they have sand in them, much less an extinguishing type,
and highly doubt their shortass arc flash distance show stopping ability 

At least with cheapo glass fuses WYSIWYG,
and any concerned owner has the option to replace with a decent rated ceramic fuse in a STANDARD  M205, 3AG or HRC format,
rather than those standup comedy midget fuses   :-DD 

 

Offline joeqsmith

  • Super Contributor
  • ***
  • Posts: 5731
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #126 on: July 16, 2017, 09:01:27 pm »
IMO, any meter, not just the AN8008, with a built-in shunt you are prone to making a mistake with it.   The 101 with an external shunt I would again say chances are slim to make that same mistake.   

And if you could get a meter which cannot measure voltage either, it would be even safer! ;)

Quote
As you mention the BM235 which is certified, so even if you do intentionally do some idiot move with the current inputs or just make a mistake, assuming you were not stupid enough to jump the fuse like some member's here, you should fair better than the AN8008 in the same case.  That's a guess on my part and if it were me, I can tell you which meter between the two I would choose hands down!   I would still say, the 101 without the current input would be a better setup.   

I have a BM257s, which I use as my "universal" meter. And I certainly intend to continue using that for anything mains-related. But the AN8008 is a neat addition for tinkering and travel use. For these purposes, I like the all-in-one functionality and the low-current and low-voltage ranges, which actually go beyond the BM257's capabilities.

I've never looked at the 257s.  For GP use I still like the 869s over any of them I have looked at.  Anymore, if I needed something with better specs for the home lab, I would just get a used name brand bench meter.   Seems like a better investment than a cheap meter.   

Yes, if you could remove the voltage input it would make the meter even safer.  I've looked at a meter like this.

https://youtu.be/7DL4OIKTnGE?t=192
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline ebastler

  • Super Contributor
  • ***
  • Posts: 2993
  • Country: de
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #127 on: July 16, 2017, 09:19:21 pm »
Yes, if you could remove the voltage input it would make the meter even safer.  I've looked at a meter like this.
https://youtu.be/7DL4OIKTnGE?t=192

;)
 

Offline tronde

  • Frequent Contributor
  • **
  • Posts: 310
  • Country: no
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #128 on: July 16, 2017, 09:40:07 pm »
People make a lot of noise about false CAT-ratings. Why don't the same people make a lot of noise about what really matters when it comes to electrical safety?

Most countries around the world have a lot of legal regulations about education and long-time experience specifying what kind of work you are allowed to do on almost ANY kind of electrical equipment or wiring.

My humble guess is that only a very few of you are legally allowed to touch anything that will require a multimeter with a CAT-rating.

So, why don't you spend your time telling beginners to stay away from what they are not allowed to do instead of all the scaremongering?

Wrong CAT-ratings are among the least thing a beginner should worry about when it comes to safety.

More idiotic reasoning. :bullshit:

Beginners need to learn, and learning entails mistakes. A newbie should be able to buy a meter that has a CAT rating that matches its capabilities. A newbie is relying on his limited knowledge to select a meter that will help protect him against his mistakes.

Who needs standards of safety?

Would you feed your baby a jar of baby food that was labelled with false safety ratings?

Would you get into a car where the seat belts were only inspected by "Inspector #22" and had little gold stickers to prove their safety?

Would you go to a doctor who had the approval for his knowledge and care by someone on a forum?

Would you recommend that your child get in that "taxi" that only has a piece of paper taped to the window that says "Taxi"?

Would you, if you like to, do a bungie jump with someone who was parked at the side of the road in their old van on a bridge and was offering "Cheap Bungie Jumps Only $10"?

Would you tell newbies to buy whatever meter they want, marked with false safety markings or not, but stay away from things they don't know about?

Oh wait, you are saying that. You are telling people who don't know what is safe or not to ignore false safety ratings.......

I shall avoid calling people names. I will leave that to you since it seems like you have a lot of experience in that subject.




I do understand that you mean well, and wish to save people from trouble. That is a good thing.

BUT- you fail badly when it comes to one most imortant thing.
 You don't understand a shit about basic psychology.

When you give the impression that you will drop dead or your house will be a smoking pile of ash just because you use a non-approved multimeter you fail. Anyone with half a brain will know that it is not true. If it had been true it would have been widely known. When a beginner reads such scaremongering he wil ask himself "is this true?"

The obvious answer will be "no, it is not true". Therefore the beginner will think that you don't understand what you are talking about, and not pay any attention to what you really want him to understand.

So, the way you act, in the name of educating, is infact extremely counterproductive.

I myself prefer to spend my words on helping people to understand why. Long time experience has told me that it is more productive than to write a lot of words most people coose to ignore







And - you didn't answer my question in the post you quoted



So, why don't you spend your time telling beginners to stay away from what they are not allowed to do instead of all the scaremongering?




All the "what about" examples you list have very little to do with electrical safety and multimeters, but they make good examples for those who want to spot scaremongers.

You mention cars. That is interesting. Do you always drive the latest cars with the most advanced safety technology?
 
The following users thanked this post: Electro Detective

Offline Lightages

  • Supporter
  • ****
  • Posts: 4295
  • Country: ca
  • Canadian po
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #129 on: July 16, 2017, 09:47:55 pm »
I won't bother replying to your rather emotional response. I will let it stand by itself.

Edit:
If anyone can show me where I call people names, or attack people personally instead of the ideas presented, I will apologize immediately.
« Last Edit: July 16, 2017, 09:59:43 pm by Lightages »
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4295
  • Country: ca
  • Canadian po
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #130 on: July 16, 2017, 09:51:58 pm »
For those who are interested, there is a sticky thread which I started in helping people avoid meters that are not rated correctly. It is factual information without emotion and drama. It has not been updated for a long time but I feel compelled to make some updates soon. Please read this thread if you want and take what you want from the information. It is presented to help, nothing more:
https://www.eevblog.com/forum/testgear/a-list-of-multimeters-that-do-not-appear-to-meet-their-claimed-safety-specs/
 

Offline tronde

  • Frequent Contributor
  • **
  • Posts: 310
  • Country: no
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #131 on: July 16, 2017, 10:10:09 pm »
I won't bother replying to your rather emotional response. I will let it stand by itself.

Edit:
If anyone can show me where I call people names, or attack people personally instead of the ideas presented, I will apologize immediately.

I am not emotional. I just want you to understand that the way you act is extremely counterproductive. You do obviously prefer to write "in big letters" so I felt that I should "adapt to the audience." Seems like you got the mesage.
From many of your posts on this forum I have got the impression that you are the "one with the answer"and have some difficulties with other peoples ideas.

If you had spent 10% of the words you have written about scaremongering on this forum on telling people about why, you would have gained thousands.



Since you can't manage to read your own text, I will paste it here "More idiotic reasoning."

 
The following users thanked this post: Electro Detective

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2105
  • Country: au
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #132 on: July 16, 2017, 10:16:23 pm »
I won't bother replying to your rather emotional response. I will let it stand by itself.

Edit:
If anyone can show me where I call people names, or attack people personally instead of the ideas presented, I will apologize immediately.

Challenge accepted !!!   ;D
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4295
  • Country: ca
  • Canadian po
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #133 on: July 16, 2017, 10:17:17 pm »
I won't bother replying to your rather emotional response. I will let it stand by itself.

Edit:
If anyone can show me where I call people names, or attack people personally instead of the ideas presented, I will apologize immediately.


Since you can't manage to read your own text, I will paste it here "More idiotic reasoning."

Is that reasoning I am attacking, or the person? You are applying idiotic reasoning. I will not apologize for attacking poor reasoning. I am responding only because I respect the opinions of others and assume that idiotic reasoning can be corrected. I also correct my own idiotic reasoning regularly.

If I assume that idiotic reasoning cannot be corrected because the other person is beyond help, I don't bother trying.
 

Offline MK14

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: gb
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #134 on: July 16, 2017, 10:21:16 pm »
In the interests of keeping this thread open for further discussions. (I.e. not giving the moderators, reason to close this thread).

Can we agree to disagree or something ?

Peoples opinions of safety and stuff like that, do vary. But it is best if it does not lead to arguments.
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4295
  • Country: ca
  • Canadian po
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #135 on: July 16, 2017, 10:42:11 pm »
In the interests of keeping this thread open for further discussions. (I.e. not giving the moderators, reason to close this thread).

Can we agree to disagree or something ?

Peoples opinions of safety and stuff like that, do vary. But it is best if it does not lead to arguments.

I wish people would agree to disagree on simple things. When people asset that safety is not worth considering and the markings on a multimeter are not to be counted in the evaluation of a multimeter, then disagreement is necessary.

When people suggest that modifying a multimeter with the intent to improve its safety is a wise, logical, or good thing to do, and that suggestion this to newbies, this needs argument. I am here trying to educate and help those who don't know better. The others are trying to shut me down for trying to show people the caution they need to take, as in education. The opposing view is to throw care out the window and too bad if you ae too stupid to know better.

I will not back down on this. Disagreements have a place. Idiotic reasoning and advice to newbies to ignore safety is to be argued.
« Last Edit: July 16, 2017, 10:56:22 pm by Lightages »
 
The following users thanked this post: MK14

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2105
  • Country: au
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #136 on: July 16, 2017, 10:50:53 pm »
In the interests of keeping this thread open for further discussions. (I.e. not giving the moderators, reason to close this thread).

Can we agree to disagree or something ?

Peoples opinions of safety and stuff like that, do vary. But it is best if it does not lead to arguments.

It's no argument, a heated debate at best, let them resolve it,

they're both big boys with literary muscle with some VERY IMPORTANT points to back up that may benefit many here,

otherwise it will flare up again and again elsewhere at other posts,

how many are complaining or offended so far?


go Team Tronde!     :clap:
« Last Edit: July 16, 2017, 10:52:26 pm by Electro Detective »
 
The following users thanked this post: MK14

Offline MK14

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: gb
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #137 on: July 16, 2017, 10:58:40 pm »
In the interests of keeping this thread open for further discussions. (I.e. not giving the moderators, reason to close this thread).

Can we agree to disagree or something ?

Peoples opinions of safety and stuff like that, do vary. But it is best if it does not lead to arguments.

I wish people would agree to disagree on simple things. When people asset that safety is not worth considering and the markings on a multimeter are not to be counted in the evaluation of a multimeter, then disagreement is necessary.

When people suggest that modifying a multimeter with the intent to improve its safety is a wise, logical, or good thing to do, and that suggestion this to newbies, this needs argument. I am here trying to educate and help those who don't know better. The others are trying to shut me down for trying to show people the caution they need to take, as in education. The opposing view is to throw care out the window and too bad if you ae too stupid to know better.

I will not back down on this. Disagreements have a place, Idiotic reasoning and advice to newbies to ignore safety is to be argued.

You have raised some good points, in this post.
Maybe I'm over-reacting, a bit.
Things have been civil in this thread, in all fairness.

Safety is very important.
But I guess, getting world-wide agreement, on what exactly safety is and what constitutes the correct level of safety. Varies from country to country.
 
The following users thanked this post: Electro Detective

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2105
  • Country: au
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #138 on: July 16, 2017, 11:01:10 pm »
Can we all agree that this meter and many like this should be de-rated to Cat 0.111 at 30 volts ?   :clap:

Same deal with the supplied leads... safe to assume they are not shop soiled Pomona seconds   ;D
 

Offline MK14

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: gb
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #139 on: July 16, 2017, 11:13:37 pm »
Can we all agree that this meter and many like this should be de-rated to Cat 0.111 at 30 volts ?   :clap:

Same deal with the supplied leads... safe to assume they are not shop soiled Pomona seconds   ;D

Part of the reason we have differing levels of safety expectancy. Is because we have a very varied and mixed audience on these forums.

On the one end of the spectrum you have Electronics professionals, who will ask, what the safest/best replacement fuses are to put in their expensive Fluke multimeter.

Then the other end of the spectrum, you can have amateur/beginner hobbyist level. Who maybe much less concerned about safety (unfortunately). Even though they probably have the most need for safe equipment, in the first place.
 

Online EEVblog

  • Administrator
  • *****
  • Posts: 29692
  • Country: au
    • EEVblog
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #140 on: July 16, 2017, 11:31:45 pm »
There is no fuse in the Fluke 101. I doesn't measure current. For that you need the Fluke 106 that doesn't heave diode measurment. Only the Fluke 107 has them all. Of course it's the most expensive. The are trying to upsell you really hard here.

Not really. There is genuine need for a voltage only meter in the electrical field. When you add current measurement you instantly make the meter more dangerous for the user and the equipment under test, as you can get the leads the wrong way around and short out your supply.
If I was an electrician I would deliberately buy a meter without current measurement.
 

Offline IanB

  • Super Contributor
  • ***
  • Posts: 9556
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #141 on: July 16, 2017, 11:38:14 pm »
Regarding making shunts, is it as simple as getting a high wattage, high accuracy resistor?

Yes.

And no.

There are dedicated current shunts available with very low resistance and four wire connection terminals for the circuit and the measurement. A search for current shunt will find many examples.
I'm not an EE--what am I doing here?
 

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2105
  • Country: au
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #142 on: July 16, 2017, 11:49:53 pm »
..There is genuine need for a voltage only meter in the electrical field. When you add current measurement you instantly make the meter more dangerous for the user and the equipment under test, as you can get the leads the wrong way around and short out your supply.
If I was an electrician I would deliberately buy a meter without current measurement.


Fluke 114 fan here, pre-tested leads and a T100 for those tasks   :-+

No current inputs means no (or less..)    'Fluke videos'   :o   type of problem 

That doesn't mean using these gives you a permit to be a confident prodder and ignore the usual 'don't trust anything or anyone' Safety Protocols!   

Fluke 114 has TRMS, MIN-MAX, an excellent Low Z function handy for ghost voltages and trip testing RCD/RCBO/GFCI,
and a good fast buzzer, and fwiw its readings pretty much agree with the 87 too
I doubt the 101 can touch it as an all rounder
ok, 114 is more money, but you only need ONE good meter for these tasks, come on don't be too cheap  :blah:

I'd rather risk the beefier 114 with it's standard quality Fluke leads going BANG! in my gloved hand or all over the shop,
than a 101, that resembles a pocket toy that no paying client would take seriously rocking up with one at a job     :wtf:  :palm:   :-DD
« Last Edit: July 17, 2017, 01:28:06 am by Electro Detective »
 

Offline IanB

  • Super Contributor
  • ***
  • Posts: 9556
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #143 on: July 17, 2017, 01:28:40 am »
There has been some discussion here about using an external current shunt to measure current where perhaps the meter cannot measure current directly (e.g. Fluke 101), and how this might relate to safety.

One important factor is that if you use a current shunt to measure current, you will (should) usually build the shunt directly into the circuit under test as a fixture. As such, the safety considerations now become considerations for the circuit and not the meter. Typically this situation should occur in a lab setting and not in the field. In the field you should probably be using a clamp meter.

Having installed the shunt into the circuit, you now can attach the meter test leads to the shunt and you have the same safety considerations with the meter as when probing any other voltage. Overall, everything should be much more controlled and predictable than trying to break a circuit and probe the current directly.
I'm not an EE--what am I doing here?
 

Offline ejeffrey

  • Super Contributor
  • ***
  • Posts: 1938
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #144 on: July 17, 2017, 03:03:07 am »
People make a lot of noise about false CAT-ratings. Why don't the same people make a lot of noise about what really matters when it comes to electrical safety?

Most countries around the world have a lot of legal regulations about education and long-time experience specifying what kind of work you are allowed to do on almost ANY kind of electrical equipment or wiring.

My humble guess is that only a very few of you are legally allowed to touch anything that will require a multimeter with a CAT-rating.

This is rather beside the point and this argument is without merit, but I am going to respond because it is also completely wrong.
 
That certainly isn't true in the US, and I don't believe it is true most places in the world.  I don't know about Norway -- maybe all the stories about the excessive regulations are true, but your description isn't true in most of the rest of Europe either.  In the US you can't operate as a professional electrician without a license, but you can do almost anything in your own house that doesn't require a building permit.  I know this isn't true everywhere, but I don't believe most places are nearly as strict as you suggest.  In most of the US that means that you can pull new circuits from the main breaker panel.  Even if you can't, you can repair existing wiring, and you can certainly measure it with a voltmeter even if you don't change anything (for instance to diagnose a problem for which you might hire an electrician to fix.

And pretty much all of the regulation that does exist stops at the wall outlet.  There is basically zero restriction on who can work on a mains powered electrical appliance.  Anyone can (legally) replace a worn power cord or troubleshoot a line operated power supply.  Of course in the CAT rating system that is only a CAT-II environment, but it is still a situation where you want a meter that is not adding any danger -- and meters with deceptive labeling are definitely something worth being upset about, even if they are totally functional for low voltage applications.

Likewise, there is no restriction (in the US) on who can work on high voltages that are not part of the power distribution system.  I have in the past worked on high voltage power supplies capable of generating from hundreds to thousands of volts.  They don't have the same power behind them as a main distribution panel, but you can still have quite a bit of energy stored in a capacitor.  There is zero certifications, regulations, or licenses for who can do that in the US.  Other countries do have mandatory engineering licenses to be a professional electronics engineer, but in most places that is only required if you are doing so professionally.  And again, it doesn't exist in the US.  There is absolutely reasons for hobbyists to have safely designed meters, even if they are not doing the specific things that the cat rating is designed for (i.e., working on power distribution networks).

I do sort of agree that many people make too big of a deal about it, as if there is no value to a meter without CAT-4 600V ratings.  There are plenty of uses for multimeters that are never anywhere near a high power / high voltage circuit. The majority of electronics hobbyists would be well served by a safety-low voltage meter, or at most one that honestly meets CATII-300V, and the features this little $25 meter has that make it attractive: high resolution and low ranges are specifically things that don't require high voltage surge capability.
 
The following users thanked this post: Someone

Offline joeqsmith

  • Super Contributor
  • ***
  • Posts: 5731
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #145 on: July 17, 2017, 03:58:12 am »
Appreciate your input joe, all read!  ;) Big fan of your robustness testing videos.


Yet more suggestions for meters to test in the future: Chauvin Arnoux MTX 32xx or any of the clamshell style ones (another major European manufacturer akin to Gossen)

I think someone else asked me about one of these some time ago.  Maybe that was you.  I looked for a distributor.  There is very little info on them.  A little advice, invoking the Gossen brand as a comparison is not a good way to sell me on a product.  It will take some time to get the bad taste out of my mouth over that ordeal.   Who knows, maybe they are actually doing something on their end.   

Why do you call it a clamshell?  I would assume it folds up based on this.    Looking over their products, I think if I were to buy one, it would be the OX 5042.  Of course when I go to the following and select the Technical document, I get 404Not Found.  Giving me lots of confidence in them from the start.

http://www.handscope.chauvin-arnoux.com/en/documents/publications.aspx


       
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline IanB

  • Super Contributor
  • ***
  • Posts: 9556
  • Country: us
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #146 on: July 17, 2017, 05:14:49 am »
Of course when I go to the following and select the Technical document, I get 404Not Found.  Giving me lots of confidence in them from the start.

I did find this: (in French, though)

http://www.handscope.chauvin-arnoux.com/Portals/0/pdf/DT_Handscope_Ed01_FR.pdf
I'm not an EE--what am I doing here?
 

Offline analogo

  • Regular Contributor
  • *
  • Posts: 79
  • Country: at
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #147 on: July 17, 2017, 08:27:56 am »
One additional detail: a few months ago I bought an UT136 on the same premises (nice meter for the price) - I did one mistake and the ohms/diode/continuity ranges are gone.

Which error?
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 9980
  • Country: 00
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #148 on: July 17, 2017, 11:12:06 am »
There has been some discussion here about using an external current shunt to measure current where perhaps the meter cannot measure current directly (e.g. Fluke 101), and how this might relate to safety.

It's MUCH safer because it eliminates a whole class of errors.

ie. You're very unlikely to connect your shunt to your mains distribution panel.   :popcorn:
 

Offline WackyGerman

  • Regular Contributor
  • *
  • Posts: 209
  • Country: de
Re: EEVblog #1007 - Is a $25 Multimeter Any Good
« Reply #149 on: July 17, 2017, 11:13:49 am »
Well it is another cheapy crappy multimeter which doesn t meet the safety regulations and labelled with the wrong CAT rating . It s built down to the price with shitty input jacks , tiny little fuses and no input protection . It s not worth the money because it will not lasting a long time , it is dangerous to use because the uA range shares the same jack with voltage ranges . Don t buy this shit , it s a waste of money .
 
The following users thanked this post: Electro Detective


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf