Author Topic: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter  (Read 299282 times)

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Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #25 on: June 30, 2017, 01:46:31 am »
 

Offline Lightages

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #26 on: June 30, 2017, 04:42:21 am »
There is absolutely no way that this thing could meet its CAT rating. When a company lies about one part, the important part, what else are they lying about. It might be an OK meter for the bench, but being marked with a lie about its safety rating means I would never buy nor recommend it to anyone. People have died using equipment that didn't meet its claimed safety rating.

I know that people are probably rolling their eyes, but I don't care. If this meter is lying around with its false ratings and someone picks it up to use it where they need the real protection because they see the marks, it could kill them or injure them severely. These falsely rated meters should be exposed here and ridiculed as the dangerous lies they are.

I have made a couple of videos that I think contribute to the problem. It is time for me to correct some things I have said in those.
 

Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #27 on: June 30, 2017, 07:39:31 am »
If this meter is lying around with its false ratings and someone picks it up to use it where they need the real protection because they see the marks, it could kill them or injure them severely.

It shouldn't be too difficult to alter the rating to something more realistic.



All fixed! You can leave it lying around now.  :popcorn:
« Last Edit: June 30, 2017, 07:42:25 am by Fungus »
 

Offline shteii01

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #28 on: June 30, 2017, 10:08:09 am »
Old Fluke 27 has two OFF positions.  One on top, one on the bottom.  So yes, the designers are being clever, but this feature has been around since late 80s, at least on Flukes.
 

Offline Lightages

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #29 on: June 30, 2017, 10:57:08 pm »
If this meter is lying around with its false ratings and someone picks it up to use it where they need the real protection because they see the marks, it could kill them or injure them severely.

It shouldn't be too difficult to alter the rating to something more realistic.

All fixed! You can leave it lying around now.  :popcorn:

Why do you troll so much?
 

Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #30 on: June 30, 2017, 11:27:34 pm »
If this meter is lying around with its false ratings and someone picks it up to use it where they need the real protection because they see the marks, it could kill them or injure them severely.
It shouldn't be too difficult to alter the rating to something more realistic.

All fixed! You can leave it lying around now.  :popcorn:

Why do you troll so much?

Who's trolling?

If somebody's likely to use that meter "where they need the real protection" based only on the numbers printed on the front then it means they know what a CAT rating is. Lowering the rating 'manually' will solve the problem.

In real life it's more likely that don't know what the numbers mean. In that case don't leave that meter lying around. Get a Fluke 101 and leave it in a prominent place.
« Last Edit: June 30, 2017, 11:30:15 pm by Fungus »
 

Offline joeqsmith

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #31 on: June 30, 2017, 11:28:39 pm »
The 8002 was pretty nice for the price.   For low voltage, low energy it's way ahead of the free meters from HR.

Because it failed at a low enough level, it made it a prime candidate to run on my half cycle generator.  Still not a lot of energy with this setup.   
https://youtu.be/HrcxnbkkhYg?t=1793

Offline Hydrawerk

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #32 on: July 01, 2017, 08:32:35 pm »
I do not like the small non-standard size fuses in AN8008.  :-- :--
Amazing machines. https://www.youtube.com/user/denha (It is not me...)
 

Offline kalel

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #33 on: July 01, 2017, 08:42:50 pm »
I do not like the small non-standard size fuses in AN8008.  :-- :--

Just wondering, what is the disadvantage of the smaller fuses? Does the fuses being smaller make arcs more likely and would that be an issue?
 

Offline Fsck

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #34 on: July 01, 2017, 09:00:55 pm »
I do not like the small non-standard size fuses in AN8008.  :-- :--

Just wondering, what is the disadvantage of the smaller fuses? Does the fuses being smaller make arcs more likely and would that be an issue?
breaking capacity will definitely be affected.
HRC fuses are filled with powder to dissipate excess energy when you severely overload the fuse.

those little guys can't possibly even have 5kA breaking capacity. Maybe not even 1kA.

obviously, if you're only on low energy circuits, this won't be an issue. just don't poke anything that might dump more than 1kA into your meter. I probably wouldn't even risk 250A
Bussmann has some videos (others probably do too) to show you how HRC fuses explode when you overload them to >100kA
"This is a one line proof...if we start sufficiently far to the left."
 

Offline plazma

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #35 on: July 02, 2017, 09:58:20 am »
Interesting. I wonder what features can be added.
I ordered 3pcs of AN8002 for adding logging output and extra buttons.
 

Offline Hydrawerk

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #36 on: July 02, 2017, 10:51:12 am »
When they want to use non-HRC fuses, at least they should use standard 5mm × 20mm fuses as most chinese DMMs do.
Amazing machines. https://www.youtube.com/user/denha (It is not me...)
 

Offline kalel

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #37 on: July 02, 2017, 11:02:12 am »
Interesting. I wonder what features can be added.
I ordered 3pcs of AN8002 for adding logging output and extra buttons.

Logging output sounds attractive, I wonder how difficult the mod is (I'm sure it was mentioned here somewhere, well worth a search or two).
 

Offline plazma

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #38 on: July 02, 2017, 11:53:10 am »
Interesting. I wonder what features can be added.
I ordered 3pcs of AN8002 for adding logging output and extra buttons.

Logging output sounds attractive, I wonder how difficult the mod is (I'm sure it was mentioned here somewhere, well worth a search or two).
IIRC it requires editing I2C ROM content. Then UART TX is enabled. I planned to add an optocoupler and a cheap CP2102  board. Also range and delta buttons would be good. 
 

Offline EEVblog

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #39 on: July 02, 2017, 11:53:22 am »
I do not like the small non-standard size fuses in AN8008.  :-- :--

Just wondering, what is the disadvantage of the smaller fuses? Does the fuses being smaller make arcs more likely and would that be an issue?

Yes, arcover wittstanding voltage, smaller breaking energy rating, they are also likely non-branded and unrated, and also the non standardness of them might be bothersome. But they are better than M205 glass fuses.
 
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Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #40 on: July 02, 2017, 12:49:12 pm »
those little guys can't possibly even have 5kA breaking capacity. Maybe not even 1kA.

obviously, if you're only on low energy circuits, this won't be an issue. just don't poke anything that might dump more than 1kA into your meter. I probably wouldn't even risk 250A
Bussmann has some videos (others probably do too) to show you how HRC fuses explode when you overload them to >100kA

I think even 20A will be very unlikely where I'm going to use mine.

If you're poking anything into undiagnosed devices with 1kA+ available then you'll need more than just a "safe" multimeter. I suggest gloves, face shield, hearing protection and somebody else standing 10 yards away with a 'phone in their hand.

When they want to use non-HRC fuses, at least they should use standard 5mm × 20mm fuses as most chinese DMMs do.

If I ever blow a fuse I'd look at replacing the socket before I tried to find those little fuses for replacement.
« Last Edit: July 02, 2017, 01:54:51 pm by Fungus »
 

Online CatalinaWOW

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #41 on: July 02, 2017, 01:41:46 pm »
I do not like the small non-standard size fuses in AN8008.  :-- :--

Just wondering, what is the disadvantage of the smaller fuses? Does the fuses being smaller make arcs more likely and would that be an issue?
breaking capacity will definitely be affected.
HRC fuses are filled with powder to dissipate excess energy when you severely overload the fuse.

those little guys can't possibly even have 5kA breaking capacity. Maybe not even 1kA.

obviously, if you're only on low energy circuits, this won't be an issue. just don't poke anything that might dump more than 1kA into your meter. I probably wouldn't even risk 250A
Bussmann has some videos (others probably do too) to show you how HRC fuses explode when you overload them to >100kA

It is going to take a lot more than a CAT rating to get me poking probes into something with capability to source 5kA for more than milliseconds.  In fact anything I work on would need to have a couple of protective devices fail to support 250A. 

Those that actually have to do this better be doing more than glancing at a label on a meter. 

Those that don't have to do this should stop and think for a long time why they think it is a good idea before proceeding.
 

Offline tronde

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #42 on: July 02, 2017, 03:16:30 pm »
Interesting. I wonder what features can be added.
I ordered 3pcs of AN8002 for adding logging output and extra buttons.

Logging output sounds attractive, I wonder how difficult the mod is (I'm sure it was mentioned here somewhere, well worth a search or two).
IIRC it requires editing I2C ROM content. Then UART TX is enabled. I planned to add an optocoupler and a cheap CP2102  board. Also range and delta buttons would be good.

Do you get access to the TX-pin on AN8002? It's easy to enable TX on the VC-921, but the TX-pin is not visble on the AN8002 as far as I know.

https://www.eevblog.com/forum/testgear/hacking-the-victor-vc-921/
 

Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #43 on: July 02, 2017, 03:41:15 pm »
The big question is: Will Dave use this chipset in his next meter?

If they can sell meters this complete for $17, how much would it cost to put in some MOVs, proper fuses, etc.?

Could somebody make a super-meter and sell it for $50?

How many UT-61Es are sold every year? That's the potential market size.  :popcorn:

 

Offline plazma

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #44 on: July 02, 2017, 06:10:48 pm »
IIRC it requires editing I2C ROM content. Then UART TX is enabled. I planned to add an optocoupler and a cheap CP2102  board. Also range and delta buttons would be good.

Do you get access to the TX-pin on AN8002? It's easy to enable TX on the VC-921, but the TX-pin is not visble on the AN8002 as far as I know.

https://www.eevblog.com/forum/testgear/hacking-the-victor-vc-921/

I quickly checked the Russian forum and it looks like no one has added TX output to this model. I guess I have to decap one to check the connections.
 

Offline Kalvin

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #45 on: July 02, 2017, 07:48:04 pm »
Bought two for general purpose low voltage measurement stuff out of curiosity. Suitable for those measurement scenarios when one runs out of multimeters :)
 

Offline kalel

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #46 on: July 11, 2017, 02:02:12 pm »
Did anyone's meter arrive yet? Any experiences? :)
 

Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #47 on: July 11, 2017, 02:21:30 pm »
Did anyone's meter arrive yet? Any experiences? :)

Still waiting for mine....

 

Offline kalel

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #48 on: July 11, 2017, 04:28:12 pm »
Did anyone's meter arrive yet? Any experiences? :)

Still waiting for mine....

I guess a couple of weeks is minimum. Although for some it will surely be faster than others (maybe some even paid extra for premium shipping?). Well, I'll be happy when someone does get a chance to share a few things about it - hopefully there's no unexpected disappointments.
 

Online Fungus

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Re: AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter
« Reply #49 on: July 11, 2017, 04:39:04 pm »
Did anyone's meter arrive yet? Any experiences? :)

Still waiting for mine....

I guess a couple of weeks is minimum. Although for some it will surely be faster than others (maybe some even paid extra for premium shipping?). Well, I'll be happy when someone does get a chance to share a few things about it - hopefully there's no unexpected disappointments.

I just checked eBay and this is what I get for delivery estimate:



(I got a tracking number, woohoo!)

eBay stuff's been taking 2 to 3 weeks to arrive recently. Maybe it'll be here next week.  :popcorn:
« Last Edit: July 11, 2017, 04:44:49 pm by Fungus »
 


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