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1129 posts

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  #2411382 2-Feb-2020 10:04
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Mark: Anyone have some pointers?

 

UNI-T UT61E





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  #2411564 2-Feb-2020 15:17
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Mark:

 

My el-cheapo multimeter seems to have gotten very inaccurate so I'm looking for a semi decent replacement, it doesn't have to be the best in the world as it'll not get used that much, just has to be accurate.

 

Anyone have some pointers ?

 

 

How cheap? How accurate?

 

My use of multimeters goes back the analogue AVO 7 and AVO 8 which were there workshop standard in those days. My approach to multi meters has been influenced through using these types of meters. My idea of cheap and/or accurate may vary to yours.

 

The first multimeters I owned were a Hioki FET VOM (high impedance input for working on electonics) and another brand which I cannot remember but both had mirror displays to remove parallax error. They were of pretty reasonable quality and accuracy but nowhere the price of the likes of the AVO's, so cheap for me.

 

My first digital muitimeter was the Goldstar DM 232 which was a Fluke look alike. It was an OK meter, cheap for me but certainly not an el cheapo. At the time I bought it I couldn't justify a Fluke. It gave good service for some time then the rotary switch started to misbehave. Changing from one setting to another would sometimes result in no reading on the display even though you were expecting to see something. No doubt you can see the problems that brought about.

 

Also the auto off function wasn't very clever in that it would always auto off at a predetermined time after being switched on no matter whether you were using it and would shut down in the middle of a measurement.

 

I put up with it for quite a while then finally I sprung for a Fluke 177.

 

The things I would look for in a meter are

 

  • Auto off
  • Auto ranging
  • Continuity tester with audible tone
  • Auto hold function with audible beep (very handy if you're unable to read the display while holding the leads)
  • Super flexible leads. (Leads that don't try to stay coiled up)
  • Clips that fit onto the probes
  • Backlight
  • Large digits
  • Bar Graph
  • Frequency counter
  • Capacitance measurement

The last two items are probably not features many would use.

 

In this day and age I think the main differences are accuracy or rather super accuracy (as most meters will provide an acceptable level of accuracy by default) and quality of components i.e. good quality plastics for the case, high tolerance components so that accuracy doesn't vary with time, good quality leads that are nice and flexible and low resistance, decent display.





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neb

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  #2411742 2-Feb-2020 23:57
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dolsen:

My flash multimeter got stolen by some lowlife so I brought the second cheapest Fluke multimeter from Dick Smith Electronics and will use that until it breaks, then I will buy a better one.

 

Sadly, it's been over 24 years now and still no sign of it dying...

 

 

Heh, I've also got a decade-old Dick Smith bought as a stand-in which is still going strong, and on its original batteries (!!). I use a proper Cat IV for any serious work, but the no-name Dick Smith just keeps on going...

neb

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  #2411743 3-Feb-2020 00:03
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Technofreak:

Also the auto off function wasn't very clever in that it would always auto off at a predetermined time after being switched on no matter whether you were using it and would shut down in the middle of a measurement.

 

 

+1 for that. Auto-off is useful to have to save batteries since it's not uncommon to put it down while taking measurements, continue on with other stuff, and forget to turn it off again, but then you want something like 15-30 minutes at least, not a minute or two.

 

 

Another thing that can be useful is non-contact voltage measurement, not to rely on it (use a proper NCV device for that) but as a quick check, and because if you're taking measurements you'll have the meter to hand anyway rather than having to dig around on a toolbox for a tiny pencil-sized NCV.

 

 

In my case the NCV I use is incredibly annoying because it won't run off rechargeables, it needs to have 1.5V or close to it so I always need to keep some AAAs around to run it.

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  #2411747 3-Feb-2020 03:21
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If you buy (too) cheap, you buy twice (and be careful with the High Voltage resilience of the El Cheapos! I don't mean what they claim for).

 

I don't care much when I crab my Fluke or the UNI-T (above) ... it differs not much except the prices (and maybe the service I never claimed as well).

 

Sure not everybody needs True RMS and some other gimmicks, but when needed, it's there for a very fair price ... or the data interface,or the PT100, or, or ... 

 

The Fluke was (once) 450 US$ and the UNI-T (recently) 49 US$ with more or less the same functions and precision included.





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- SVR: E3C236 32G/24T, 2 H2 16G/500G, N2 4G/1T || remote HC2 14T, HC2 4T
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- ipPBX: GO-Box, 2 GRP2613, SPA112 (Fax & W-48, a 1948 Siemens phone)

 

 


453 posts

Ultimate Geek


  #2411814 3-Feb-2020 10:20
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michaelmurfy:

 

I've bought one of these ones from Banggood: ANENG AN8008

 

For the price I paid I am very impressed with it. The one I got is accurate enough, I've used it on mains voltage, the leads feel great and the general build construction is great. Auto ranging also. I don't use it often but it has been reliable for when I've needed it.

 

 

 

Cheers. Just bought the 8009 based on a bunch of videos. Seems much better than a Jaycar option.


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  #2411845 3-Feb-2020 10:51
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Fluke made a video comparing one of their standard meters vs a cheap one bought off ebay. I can't find it right now but they put the cheap one in an isolated box and had a remote arm turn the dial. It was connected to an energised 400V source. The multimeter was rated for 400V measurements. They showed on voltage it was displaying 400V. All fine so far. Then he said what happens if you make a mistake and twist the dial from the 400V measurement mode to something else. It blew up with a loud bang. He did the smae with the Fluke holding it in his hand and the device measured 400V, then flicked to resistance I think and it went blank. Turned it off and on and it measered the 400V again. He said sure they work OK if you never make a mistake, but if you accidentally choose the wrong setting or measure something which is a higher V than you are expecting you are in serious danger.


 
 
 
 


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  #2411859 3-Feb-2020 11:16
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Varkk:

 

Fluke made a video comparing one of their standard meters vs a cheap one bought off ebay. I can't find it right now but they put the cheap one in an isolated box and had a remote arm turn the dial. It was connected to an energised 400V source. The multimeter was rated for 400V measurements. They showed on voltage it was displaying 400V. All fine so far. Then he said what happens if you make a mistake and twist the dial from the 400V measurement mode to something else. It blew up with a loud bang. He did the smae with the Fluke holding it in his hand and the device measured 400V, then flicked to resistance I think and it went blank. Turned it off and on and it measered the 400V again. He said sure they work OK if you never make a mistake, but if you accidentally choose the wrong setting or measure something which is a higher V than you are expecting you are in serious danger.

 

 

I watched that. I wont be doing AC - only low voltage.


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Master Geek


  #2411918 3-Feb-2020 14:54
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+1 for the Aneng. Bought an AN8009 a few months ago based on Eevblog and others and it has been fine. The leads are pretty basic but can be replaced easily. I didn't see much point spending more when it's just for hobby use and no mains voltage.

neb

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  #2411928 3-Feb-2020 15:14
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Varkk:

Fluke made a video comparing one of their standard meters vs a cheap one bought off ebay.

 

 

Just don't attach too much weight to that sort of comparison, they're obviously going to find the crappiest meter they can to compare to their own, so just because the crappy one catches fire doesn't mean there aren't lots of non-Fluke meters that won't be fine. That is, you can get Fluke-level quality without paying Fluke-level prices.

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  #2411965 3-Feb-2020 16:14
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Batman:

 

richms:

 

Batman:

 

question: can you use a multimeter to check if disposable batteries are full or empty?

 

 

Sort of. You can tell a full one because it will be about 1.6v, you can tell a dead one because it will be 0.something volts. But you cant tell how far down they are inbetween since that will change on the load, and a multimeter puts no load on the cell. Real battery testers pull a few 100mA from the cell and show the voltage. A good one will have lots of voltage there, but an almost dead one will have the voltage drop, but will still have ok voltage when checked with no load.

 

 

ah that makes sense. all my batteries that don't power anythnig have normal voltages. need a tool that draws current and look for voltage drop. got it.

 

 

I use the 10A range on Digi MM to test for battery capacity. The internal battery resistance limits any dangerous currents.

 

NiCad/NiHi and C-Zn, and Alkaline can be tested this way. Wouldn't try it on lithium chemistries as they have quite a low internal resistance.

 

A fresh AA NiCad delivers about 4.5A, fresh AA Alkaline, around 3.6A. Different meters will read different currents, even on the same 10A range.

 

A flat battery will still show usable voltage, but because the digi MM has such a high input impedance, there  is no load, and will read a good voltage even though it will drop significantly under any load.

 

A battery that still delivers 1A may not be good for a battery op toy or torch, but still perfectly usable in digi clocks and remote controls for a good few extra months.

 

Just make sure you test for less than a second - long enough for the reading to settle.

 

 





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  #2412799 5-Feb-2020 08:17
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Thanks for all the good replies :)


110 posts

Master Geek


  #2413027 5-Feb-2020 13:04
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I quite like modern UNI-T stuff. Some of their older meters promised higher CAT ratings than they could possibly offer, but their newer meters are much better (still wouldn't trust the label, but most of them are at least reasonably built).

 

If you want something smaller, check out the Uni-T UT 120C. It's a great little pocket meter for electronics work.

 

I'm also quite happy with my UT139C that I bought from AliExpress. There are a few sellers with good reputation that seem to specialise in testing equipment - search them out, most of their stuff appears to be legitimate.

 

There's also a neat little clamp meter that can measure DC current using the clamp itself with a 2A range - the UT210E. Super handy for doing stuff in the car etc.


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  #2415505 10-Feb-2020 11:28
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neb:
Technofreak:

 

Also the auto off function wasn't very clever in that it would always auto off at a predetermined time after being switched on no matter whether you were using it and would shut down in the middle of a measurement.

 

+1 for that. Auto-off is useful to have to save batteries since it's not uncommon to put it down while taking measurements, continue on with other stuff, and forget to turn it off again, but then you want something like 15-30 minutes at least, not a minute or two.

 

I really don't understand why Auto-power-off is a desirable feature. It is something people seem to repeat without giving a moments though to. It is usually a false economy feature, both time and money wise. As mentioned, most are dumb, turning off regardless of what is going on, cause repeated interruption to work, 2nd, DMM's just don't use enough power to warrant it - the batteries last forever, often leaking before they go flat negating/eclipsing any battery replacement savings), 3rd DMM's are often used to monitor circuits (battery charging progress, erratic/intermittent faults etc) and auto-power off is a PITA in these cases. 


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Master Geek


  #2415679 10-Feb-2020 19:12
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For a bench meter where it's generally in view and used frequently I would agree.

 

 

 

For a field meter that might get put back in the case switched on, it can be a right PITA to pull it back out a week later and find out it's flat.


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