Products > Test Equipment
What's the cheapest 0.02% accuracy handheld meter
miegapele:
--- Quote from: bdunham7 on July 12, 2023, 10:42:03 pm ---The devil is in the details. A stated 0.02% 'basic DC accuracy' is not a complete spec.
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I'm very well aware of that, but that is how data is usually presented everywhere, including Fluke website
--- Quote from: CosteC on July 13, 2023, 06:53:13 am ---I am rather on conservative end when it comes to datasheet performance. While my old APPA 72 has "only 0.5%" is it far more stable than cheap chinese no-brand multimeter which drifts with battery depleting.
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No reasonable multimeter with 0.0X% spec will drift with battery voltage. Only the king of multimeters, that is DT830 is allowed to do that.
--- Quote from: CosteC on July 13, 2023, 06:53:13 am ---Most magic question for me is what hobbyst application calls for 0.03% accuracy and how to validate this accuracy in hobby environment?
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Simple, It's called "I want". Actually 99% of the forum discussions here is based on precisely that application.
--- Quote from: CosteC on July 13, 2023, 06:53:13 am ---I appriciate AN870 declared accuracy, yet I do not trust it too much in long term...
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Any references to that? Other posted provided evidence that it's fine.
--- Quote from: CosteC on July 13, 2023, 08:13:38 am ---
2) What manufacturer? https://anengmultimeter.com/ Sells clothing... Aliexpress shop?
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Manufacturer is irrelevant, unless you buy your Fluke for status, that is.
--- Quote from: CosteC on July 13, 2023, 08:13:38 am ---
3) Reference is only one thing among many responsible for accuracy. None is particularly recognizable or look stable
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Reference is probably most important thing still, look at any teardown Dave does, reference always gets lots of attention. And also how do you determined that its not stable?
--- Quote from: CosteC on July 13, 2023, 08:13:38 am ---
Is it resistant to radio interference? Rather not.
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Why this matters? I'm not sure that's common design criteria for multimers.
--- Quote from: CosteC on July 13, 2023, 08:13:38 am ---
1) Manufacturer does not provide anything remotly similar to proper specifications. What is long term drift? Nobody knows.
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Whats long term drift on Fluke? I doubt anybody knows either.
--- Quote from: bdunham7 on July 13, 2023, 12:59:55 pm ---But if I take it for a 50-mile drive out in the mountains and while testing some equipment (indoors, room temperature) I take a measurement of 7.492V, what is my confidence level that this reading is accurate to within a certain amount, say 6 counts?
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What kind of guarantee Fluke provides here? Do they spec their multimeter for altitude?
miegapele:
Thank you all foe great advice.
I guess I need to start saving money to buy Brymen for Christmas ;)
mwb1100:
So the conclusions of this thread to get an inexpensive multimeter with high basic accuracy (0.05% or better) as specified/claimed by the manufacturer seem to boil down to:
1. the best you can do for basic accuracy in a 50-ish EUR/USD meter is 0.05%
2. if you want 0.02 - 0.03% basic accuracy, you will need to move to a 150-200-ish EUR/USD price range and likely a Brymen BM78x, BM85x, or BM86x
(of course this is a simplistic analysis that ignores how accurate the manufacturers claims are, the stability of the meter's accuracy, the number of counts involved in the accuracy, etc)
bdunham7:
--- Quote from: miegapele on July 13, 2023, 03:31:56 pm ---What kind of guarantee Fluke provides here? Do they spec their multimeter for altitude?
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They do spec for altitude and a lot of other things. In this case for a 289, as long as the indoor temp is between 18 and 28C, the RH is less than 90% and the alititude is under 3000M, they guarantee that a voltage of 7.492 will result in a reading between 7.488 and 7.496V, or conversely that a reading of 7.492 indicates an actual voltage from 7.488 to 7.496.
But this meter (the Fluke 289) would not meet your specified goal of having an 'advertised accuracy' of 0.02%. You can buy a Brymen 869S which does have an advertised "DC basic accuracy" of 0.02%, but alas on the 50V range it is 0.03% + 2 counts and is only specified to 2000M altitude and 80%RH. A strong contender, but not the winner. :)
--- Quote ---Reference is probably most important thing still, look at any teardown Dave does, reference always gets lots of attention. And also how do you determined that its not stable?
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Of course the reference is critical, but it is not the hardest or most expensive component to optimize. The thing that distinguishes the excellent from the average is the ability to produce (or source) high-quality resistors.
AVGresponding:
--- Quote from: Fungus on July 13, 2023, 11:24:29 am ---
--- Quote from: AVGresponding on July 13, 2023, 11:16:15 am ---In context, it means the best quality (in terms of performance, construction and warranty) in a device that meets the task criteria.
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So now you have to define "the task".
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That's the job of whoever is buying the meter. I can't define it for someone else.
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