EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: D.Kruger on February 15, 2021, 08:40:57 am
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Hi everyone,
In my company we are going to buy 5 multimeters. I was looking different models and so far, the best I've found are Uni-t ut139e and Peaktech 2025.
I have a ut139c and I'm quite happy with it, but is missing the datalogging capabilities of the Peaktech. I don't know if we ended up using the datalogging a lot but my superior mentioned as a nice bonus.
Does anyone know a better multimeter for around 50€?
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D.Kruger - UNIT UT61E+ ;)
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If you're only spending 50€, having logging on it probably means less quality in another area. So, if you're not sure you'll ever use it: don't bother.
Also: USB on a DMM makes me cringe.. :scared:
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If you're only spending 50€, having logging on it probably means less quality in another area. So, if you're not sure you'll ever use it: don't bother.
Or get one that can log, just in case.
Also: USB on a DMM makes me cringe.. :scared:
They're optically isolated.
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Hi everyone,
In my company we are going to buy 5 multimeters. I was looking different models and so far, the best I've found are Uni-t ut139e and Peaktech 2025.
I have a ut139c and I'm quite happy with it, but is missing the datalogging capabilities of the Peaktech. I don't know if we ended up using the datalogging a lot but my superior mentioned as a nice bonus.
Does anyone know a better multimeter for around 50€?
You left out the single most important piece of information: What will they be used for?
(Yes, we know - "Everything!!!", but what will be their main, everyday use?)
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Also: USB on a DMM makes me cringe.. :scared:
They're optically isolated.
Probably. Still makes me cringe. Either it's well done and then a lot of budget went in adding logging/USB or it's not and then I don't want it anywhere near a bench where I'm working.
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They're optically isolated.
Probably. Still makes me cringe. Either it's well done and then a lot of budget went in adding logging/USB
It's just two LEDs and a transparent bit in the back of the case, no more complicated than a TV remote control.
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They're optically isolated.
Probably. Still makes me cringe. Either it's well done and then a lot of budget went in adding logging/USB
It's just two LEDs and a transparent bit in the back of the case, no more complicated than a TV remote control.
To make a fully isolated USB connection? :o
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It's just two LEDs and a transparent bit in the back of the case, no more complicated than a TV remote control.
That is the way it is done on meters with a external adapter, with build-in USB the isolation may not be nearly as good, especially with cheap Chinese meters. I have tested one meter without isolation to the build-in USB connector (I do not remember what meter) and a couple with very low creepage distance.
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Hence my remark that it makes me cringe.
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You left out the single most important piece of information: What will they be used for?
(Yes, we know - "Everything!!!", but what will be their main, everyday use?)
The main use will be low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability.
For less common occasions I might need to measure mains AC one in a while, but not that important.
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To make a fully isolated USB connection? :o
It's not "USB", it's a serial connection. The only thing that's USB is the plug on the end of the cable.
It's just two LEDs and a transparent bit in the back of the case, no more complicated than a TV remote control.
That is the way it is done on meters with a external adapter, with build-in USB the isolation may not be nearly as good, especially with cheap Chinese meters. I have tested one meter without isolation to the build-in USB connector (I do not remember what meter) and a couple with very low creepage distance.
I've never seen a meter with a USB connector on it. I've only seen LEDs/transparent plastic.
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To make a fully isolated USB connection? :o
It's not "USB", it's a serial connection. The only thing that's USB is the plug on the end of the cable.
It's just two LEDs and a transparent bit in the back of the case, no more complicated than a TV remote control.
That is the way it is done on meters with a external adapter, with build-in USB the isolation may not be nearly as good, especially with cheap Chinese meters. I have tested one meter without isolation to the build-in USB connector (I do not remember what meter) and a couple with very low creepage distance.
I've never seen a meter with a USB connector on it. I've only seen LEDs/transparent plastic.
That's how the regular brands do it. There's too little info to be sure but everything points to a "direct" USB connection.
https://www.peaktech.de/productdetail/kategorie/digital---handmultimeter/produkt/p_2025.html (https://www.peaktech.de/productdetail/kategorie/digital---handmultimeter/produkt/p_2025.html)
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The main use will be low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability.
You can easily use (eg.) an Arduino for logging low voltage DC. It can do multiple channels, too, and high speed if needed. Handheld meters will only send a couple of values per second.
As for the meter: Go with the UT139C that you know or get some Anengs. These are good: https://es.aliexpress.com/item/33004463675.html (https://es.aliexpress.com/item/33004463675.html)
Reliability? There are exceptions but I think it's more productive to have lots of meters around to cross-check weird readings than to aim for a perfect meter.
Whatever meter(s) you go for, budget enough to get some nice gold-plated test leads to go with them. They do make a difference and they don't have to be expensive, eg. these are much better than the leads that came with my Aneng: https://www.aliexpress.com/item/33006553337.html (https://www.aliexpress.com/item/33006553337.html)
For less common occasions I might need to measure mains AC one in a while, but not that important.
For occasional use you'll be safe with the meters above.
Correct procedure is at least as important as the meter (check three times that the leads are in the right holes and the selector switch is in the right place, wear a glove, don't do anything risky without somebody else around to notice if you scream and fall over, that sort of thing...)
Do all these meters have to be identical? Get a cheap Brymen or Fluke 101 to complement the others.
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I've never seen a meter with a USB connector on it. I've only seen LEDs/transparent plastic.
You mean like this: (https://lygte-info.dk/pic/Victor/98A%2B/DSC_4815.jpg)
Review of above meter: https://lygte-info.dk/review/DMMVictor%2098A%20UK.html (https://lygte-info.dk/review/DMMVictor%2098A%20UK.html)
Or this: (https://lygte-info.dk/pic/Mastech/MS8340B/DSC_4231.jpg)
Review of above meter: https://lygte-info.dk/review/DMMMastech%20MS8340B%20UK.html (https://lygte-info.dk/review/DMMMastech%20MS8340B%20UK.html)
Or this: (https://lygte-info.dk/pic/BSide/ADM20/DSC_3044.jpg)
Review of above meter: https://lygte-info.dk/review/DMMBSide%20ADM20%20UK.html (https://lygte-info.dk/review/DMMBSide%20ADM20%20UK.html)
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That's how the regular brands do it. There's too little info to be sure but everything points to a "direct" USB connection.
https://www.peaktech.de/productdetail/kategorie/digital---handmultimeter/produkt/p_2025.html (https://www.peaktech.de/productdetail/kategorie/digital---handmultimeter/produkt/p_2025.html)
They claim IEC 61010-1 + CAT III 600V so it must be isolated somehow. :-//
(https://www.eevblog.com/forum/testgear/best-multimeter-for-~50/?action=dlattach;attach=1174400;image)
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I've never seen a meter with a USB connector on it. I've only seen LEDs/transparent plastic.
You mean like this:
Or this:
Or this:
...
OK, OK, they exist. :)
That BSide meter has the USB interface on a separate board and LEDs for communication:
(https://lygte-info.dk/pic/BSide/ADM20/DSC_3059a.jpg)
I'd like to see a bit more more gap between the two PCBs though.
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They claim IEC 61010-1 + CAT III 600V so it must be isolated somehow. :-//
And because it is sold by a German company it is probably correct, but I would not trust a direct USB connection on a meter directly from China.
With the 3 examples I posted before, only one looks good (Mastech), the two other have rather short isolation/creepage distances.
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They claim IEC 61010-1 + CAT III 600V so it must be isolated somehow. :-//
And because it is sold by a German company it is probably correct, but I would not trust a direct USB connection on a meter directly from China.
The Chinese are starting to put Bluetooth in their cheapo meters. I wonder what the protocols are like.
https://www.aliexpress.com/item/1005001525757614.html (https://www.aliexpress.com/item/1005001525757614.html)
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The main use will be low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability.
You can easily use (eg.) an Arduino for logging low voltage DC. It can do multiple channels, too, and high speed if needed. Handheld meters will only send a couple of values per second.
As for the meter: Go with the UT139C that you know or get some Anengs. These are good: https://es.aliexpress.com/item/33004463675.html (https://es.aliexpress.com/item/33004463675.html)
Reliability? There are exceptions but I think it's more productive to have lots of meters around to cross-check weird readings than to aim for a perfect meter.
Whatever meter(s) you go for, budget enough to get some nice gold-plated test leads to go with them. They do make a difference and they don't have to be expensive, eg. these are much better than the leads that came with my Aneng: https://www.aliexpress.com/item/33006553337.html (https://www.aliexpress.com/item/33006553337.html)
For less common occasions I might need to measure mains AC one in a while, but not that important.
For occasional use you'll be safe with the meters above.
Correct procedure is at least as important as the meter (check three times that the leads are in the right holes and the selector switch is in the right place, wear a glove, don't do anything risky without somebody else around to notice if you scream and fall over, that sort of thing...)
Do all these meters have to be identical? Get a cheap Brymen or Fluke 101 to complement the others.
Thanks for the idea, then I will buy different models instead of the same one 5 times.
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Thanks for the idea, then I will buy different models instead of the same one 5 times.
Perfect! :-+
(and if you're ever in Valencia then drop by...)
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D.Kruger - UNIT UT61E+ ;)
Thanks for the recommendation, I saw the thread in the forum about this meter but I couldn't find to much info about the safety levels of the meter so I was worried as I know the poor safety standards of the old one
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I couldn't find to much info about the safety levels of the meter so I was worried as I know the poor safety standards of the old one
It doesn't have independent certification so who knows? Uni-T has a history of making different versions of their meters that look the same on the outside but have completely different safety components inside.
eg. https://www.eevblog.com/forum/testgear/dmm-recommendation-help/msg3463952/#msg3463952 (https://www.eevblog.com/forum/testgear/dmm-recommendation-help/msg3463952/#msg3463952)
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D.Kruger - UNIT UT61E+ ;)
Thanks for the recommendation, I saw the thread in the forum about this meter but I couldn't find to much info about the safety levels of the meter so I was worried as I know the poor safety standards of the old one
You can estimate the safety of this new model from the photo of the filling.
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Perfect! :-+
(and if you're ever in Valencia then drop by...)
I live in Valencia, what a small world! ;D
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I live in Valencia, what a small world! ;D
PM sent.
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You left out the single most important piece of information: What will they be used for?
(Yes, we know - "Everything!!!", but what will be their main, everyday use?)
The main use will be low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability.
That still doesn't help much. I mean what is acceptable precision. What are your calibration requirements and maybe more importantly what does you local cal lab support well. Buying meters for production (an assumption here) is more than just looking at the purchase price.
For less common occasions I might need to measure mains AC one in a while, but not that important.
It is very important if you want to be safe doing so.
Some advice:
- Don't make purchase decisions on features you are not likely to use.
- Many of those extra features implemented on the cheap meters are crap anyways.
- It is foolish to set the budget before you have determined exactly what you need.
- 50 euro's is probably close to $60. There are actually a lot of meters available in that price range. However at the lower end they are basically crap meters.
- However will the meters have enough resolution for the testing you will be doing? Consider any usage of D/A or A/D converters and the number of bits needed to verify operation of these devices. This is the problem with setting a price before you determine need.
- The cost of maintenance should not be ignored. Here I'm talking mostly about a calibration program. You can easily end up spending more on calibration than the cost of the meters. Frankly calibration might be required depending upon the industry you are serving.
- You might be better off buying higher end meters over time if you are not pressed to buy now. It is hard to tell from your posted info.
Maybe somebody else can add to the blank lines above but the above comes off the top of my head. In any event there are as I said many handheld meters in this price range. You might want to look at offering from Flir, B&K Precision, Amprobe and others. Pop up a distributor, such as Digikey, listing of meters and you will see dozens of meters in this price range.
In any event I'm left with the impression that you are jumping into a buy before knowing what your requirements are. I'm not one to get on the high count bandwagon like 50,000 or 100,000 count hand held DMM's but sometimes the resolution is required (by the way resolution does not imply accuracy). More importantly sometimes you are better off using a bench multi meter.
Not everyone needs a Fluke 87 series multimeter but almost everyone is better off with something better than a bargain basement meter. The trick you must pull off is finding the best fit for your needs. I'd go the B&K Precision route at the price point you are discussing as it si my best guess at what would fit your needs.
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Thanks for the detailed reply, these are a lot of things that I hadn't consider. I'm going to do more research in what we actually need for our projects before buying the meters
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Some advice:
- Don't make purchase decisions on features you are not likely to use.
- Many of those extra features implemented on the cheap meters are crap anyways.
You won't save money by not having features - even the cheap meters have all the features these days. The only way to really have less features is to buy a Fluke.
I own lots of cheap meters so I know that not all of them are crap. Some of them are really very good.
- It is foolish to set the budget before you have determined exactly what you need.
That's literally what budgets are - a price that's set before going out to make a purchase.
- The cost of maintenance should not be ignored. Here I'm talking mostly about a calibration program. You can easily end up spending more on calibration than the cost of the meters. Frankly calibration might be required depending upon the industry you are serving.
The advantage of owning many meters is that you can cross-check them against each other. As far as I can tell, meters don't drift out of specification any more (if they ever did).
As far as I can tell the only valid argument for regular calibration is for legal reaons, ie. you need the pretty certificates if you're doing something that might expose you to lawsuits.
You might want to look at offering from Flir, B&K Precision, Amprobe and others. Pop up a distributor, such as Digikey, listing of meters and you will see dozens of meters in this price range.
Those are all brands that almost never appear here in relation to multimeters. There's a reason for that.
Not everyone needs a Fluke 87 series multimeter but almost everyone is better off with something better than a bargain basement meter.
I would never personally buy a Fluke 87 because I know about Brymen. You'd have to offer me the Fluke for about $125 to get me to buy it, which isn't going to happen.
In any event I'm left with the impression that you are jumping into a buy before knowing what your requirements are.
The requirements were clearly stated above, ie: "low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability. For less common occasions I might need to measure mains AC one in a while, but not that important."
My 20,000 count Aneng 870 will easily do that, so will the Uni-T UT139C that the poster is familiar with. Both are far enough under the 50 Euro budget to add gold plated test leads (with a spare set!) and maybe even add a Fluke 101 as well for the times you want to look at mains or need a second meter for measuring volts/amps simultaneously.
The only unknown requirement was for data logging but could easily buy 4x cheapo meters and one logging meter or do the logging using an MCU.
(PS: For checking the buses of I2C/SPI you really need an oscilloscope to see the signals...)
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Some advice:
- Don't make purchase decisions on features you are not likely to use.
- Many of those extra features implemented on the cheap meters are crap anyways.
You won't save money by not having features - even the cheap meters have all the features these days. The only way to really have less features is to buy a Fluke.
You missed my point which was that you should only buy based on features you know you need. The extraneous stuff should not be a factor in purchase.
I own lots of cheap meters so I know that not all of them are crap. Some of them are really very good.
I've seen my share of low cost meters and as you say some are really good. Go too low and you end up with crap. Thankfully his budget allows for the purchase of a decent meter.
- It is foolish to set the budget before you have determined exactly what you need.
That's literally what budgets are - a price that's set before going out to make a purchase.
You don't set the price until you determine what you need. That is like a construction firm setting a price for a bulldozer at $25,000 and not being able to buy a bulldozer because nothing is available in that price range to do the job they have in mind. The idea that you can pull a price out of your behind and then get what you need is asinine. Any place I've been you are expected to research your needs and then present a plan for budgeting.
The only thing good here is that there is plenty of product available in the price range. That is from dozens of manufactures so they may very well find a solution once they know their needs.
- The cost of maintenance should not be ignored. Here I'm talking mostly about a calibration program. You can easily end up spending more on calibration than the cost of the meters. Frankly calibration might be required depending upon the industry you are serving.
The advantage of owning many meters is that you can cross-check them against each other. As far as I can tell, meters don't drift out of specification any more (if they ever did).
Cross checking is not calibration.
As far as I can tell the only valid argument for regular calibration is for legal reaons, ie. you need the pretty certificates if you're doing something that might expose you to lawsuits.
Many of us actually working in such industries so that is why calibration comes up. It isn't just a pretty certificate and can mean the difference between running your business or getting shut down by the FDA. Insert your own government body here, the point is calibration can be a critical part of owning instrumentation.
By the way I'm not one to agree with the extent that an organization has to go to to meet regulation but these regulations usually come about due to lessons learned. By the way I've seen records, either calibration or engineering, save a company tons of time and effort figuring out where a process is having problems. Paperwork isn't always fun but there is a reason for the process.
You might want to look at offering from Flir, B&K Precision, Amprobe and others. Pop up a distributor, such as Digikey, listing of meters and you will see dozens of meters in this price range.
Those are all brands that almost never appear here in relation to multimeters. There's a reason for that.
OK tell us what that reason might be?
Not everyone needs a Fluke 87 series multimeter but almost everyone is better off with something better than a bargain basement meter.
I would never personally buy a Fluke 87 because I know about Brymen. You'd have to offer me the Fluke for about $125 to get me to buy it, which isn't going to happen.
Brymen isn't the last word in meters. There are god reasons to prefer Fluke in many cases. The same could be said about HPAK or the other instrument manufactures. Each has a niche to fill.
In any event I'm left with the impression that you are jumping into a buy before knowing what your requirements are.
The requirements were clearly stated above, ie: "low voltage low current electronics: embedded systems, MCU boards, I2C/SPI connections... things with voltages under 5V and currents under 500mA. What a want basically is to measure the values with good precision and reliability. For less common occasions I might need to measure mains AC one in a while, but not that important."
That isn't clear at all to me which resulted in my question about A/D and D/A hardware. Embedded systems often contain such hardware and the resolution can vary from 12 bit on up at some point the meter chosen will make a difference if this is the case.
My 20,000 count Aneng 870 will easily do that, so will the Uni-T UT139C that the poster is familiar with. Both are far enough under the 50 Euro budget to add gold plated test leads (with a spare set!) and maybe even add a Fluke 101 as well for the times you want to look at mains or need a second meter for measuring volts/amps simultaneously.
If there is any possibility at all of working at higher voltages than seen in digital systems then every meter they buy should be safe in that context. There is always the issue of somebody grabbing the first meter available and exposing themselves to risk.
The only unknown requirement was for data logging but could easily buy 4x cheapo meters and one logging meter or do the logging using an MCU.
Data logging in a handheld meter is another one of those feel good features that is basically little value for most users. It is sort of like a capacitance function, it can make you feel good but it is no substitute for a proper approach. If you are to engage in a lot of data logging at the bench you are better off buying the right hardware and hooking it up to a PC to collect that data.
(PS: For checking the buses of I2C/SPI you really need an oscilloscope to see the signals...)
As a complete aside another way to look at the importance of calibration and paying for better quality instruments is to consider the common combination square. Back in the day I bought a cheapo hardware store square and started in on a project. Sadly things where no coming out right. Eventually I realized that the square used to set everything up with was in fact not so square. Realizing that it went into the trash after which I purchased a nice Starrett. That square was square right out of the box - nice. Then I learned how to check a square like that for accuracy, so that I would always have confidence in the square. Not a calibration mind you but a check. That was a lesson hard learned in my teen years.
Now after dozens of years of experience in the industrial sector I've come to realize that there is value in buying quality over cheap. It is up to the buyer to sort the junk from the respectable stuff out there.
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You missed my point which was that you should only buy based on features you know you need. The extraneous stuff should not be a factor in purchase.
And you missed mine which was that cheapo meters are so complete these days that their feature set isn't even a factor in a purchase decision. You'd have to spend a lot of money to get more features than a $30 Aneng/Uni-T (you'll probably find the features dip downwards as you go towards $80 "quality" brands)
Cross checking is not calibration.
I never said it was. My point was that when you own several meters it's easy to find out if they're working correctly or not - just measure the same thing on a few different meters, see if they agree. There's no need to pay any money for that.
If you need legal coverage then it's a different matter, as I pointed out.
https://blog.wika.com/knowhow/calibration-or-adjustment-wheres-the-difference/ (https://blog.wika.com/knowhow/calibration-or-adjustment-wheres-the-difference/)
You might want to look at offering from Flir, B&K Precision, Amprobe and others. Pop up a distributor, such as Digikey, listing of meters and you will see dozens of meters in this price range.
Those are all brands that almost never appear here in relation to multimeters. There's a reason for that.
OK tell us what that reason might be?
Ummm... let's see. A forum full of hundreds of professional engineers who work in the field at all levels. Special section for test gear. Regular dissections of multimeters right down to the last resistor. Not a single one of those engineers arguing in favor of any of those brands, nobody seems to even own them.
Conclusion: "Professional" meters in that price range are not good value for money or particulary worth owning.
We also know that they're mostly rebrands of other meters just to fill out their product lines, ie. they have no particular interest in making multimeters, only money. https://www.eevblog.com/forum/testgear/flir-multimeters-who-is-the-oem/ (https://www.eevblog.com/forum/testgear/flir-multimeters-who-is-the-oem/)
https://www.youtube.com/watch?v=Ewyf9mzIfi0 (https://www.youtube.com/watch?v=Ewyf9mzIfi0)