Author Topic: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)  (Read 229230 times)

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Offline Wytnucls

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #275 on: February 09, 2015, 11:22:44 am »
Just opened my UT61B bought for 58€ in a brick and mortar shop (40 less than the next cheapest: the Brymen i really wanted including postage) last northern hemisphere summer.
I seems to have the input protection and proper fusing. It's quite ok and well built for the price.
And if the 61B(GS) 200107-7 code mean that the PCB was designed then? If that's the case, they've been able to do so since at least 2001!
It looks like you have a GS version modified with the old original BS1362 fuses in place and all MOVs removed. Not good.
« Last Edit: February 09, 2015, 11:33:48 am by Wytnucls »
 

Offline gildasd

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #276 on: February 09, 2015, 11:34:13 am »
It's quite ok and well built for the price.
And if the 61B(GS) 200107-7 code mean that the PCB was designed then? If that's the case, they've been able to do so since at least 2001!

The problem is that the management of that company feel it's OK to lie to customers and rip them off.

There's alternatives out there. Uni-T don't really deserve anybody's business until there's nothing but well built meters in their lineup and they've recalled all the bad ones from stores.

OK, they're not going to do that but they should at the very least remove the CAT-IV labels and market them for what they are.

Plus HRC fuses and proper track clearances aren't that expensive to do. That's pretty much all it would take to bump the safety up by an order of magnitude.
Right now, my only alternative are the yellow hard plastic 5€ jobbies from the hardware store... I don't want those, even for free.
Your video only reinforced that belief ;)

Anyway you look at it, I'm not getting another UNI-T unless/until they clear up their rating and the manufacturing issues.
As a client I should get what it  says on the box, not gamble that I might...
« Last Edit: February 09, 2015, 11:38:22 am by gildasd »
I'm electronically illiterate
 

Offline EEVblogTopic starter

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #277 on: February 09, 2015, 11:51:57 am »
Does it say that anywhere other than buried deep within the Users Guide? I could forgive someone for thinking that a U1232A would have a decent mA range contained within the A range just as it has mV ranges contained within it's V range.

I thought it was pretty obvious from the front panel. It doesn't say mA/uA or mA/A like most meters do.
 

Offline gildasd

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #278 on: February 09, 2015, 11:53:04 am »
Just opened my UT61B bought for 58€ in a brick and mortar shop (40 less than the next cheapest: the Brymen i really wanted including postage) last northern hemisphere summer.
I seems to have the input protection and proper fusing. It's quite ok and well built for the price.
And if the 61B(GS) 200107-7 code mean that the PCB was designed then? If that's the case, they've been able to do so since at least 2001!
It looks like you have a GS version modified with the old original BS1362 fuses in place and all MOVs removed. Not good.
That opens up a few questions:
- Can I solder some on?
- What should be they be rated at?
- Should someone start a thread on "How to make your UT61 less crap for a couple of Euros" (by someone competent, I'm not).
I'm electronically illiterate
 

Offline TMM

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #279 on: February 09, 2015, 11:57:07 am »
Does it say that anywhere other than buried deep within the Users Guide? I could forgive someone for thinking that a U1232A would have a decent mA range contained within the A range just as it has mV ranges contained within it's V range.

I thought it was pretty obvious from the front panel. It doesn't say mA/uA or mA/A like most meters do.
It also doesn't say mV or have a dedicated switch position for it, but it does measure mV.
 

Offline Fungus

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #280 on: February 09, 2015, 12:16:41 pm »
Right now, my only alternative are the yellow hard plastic 5€ jobbies from the hardware store... I don't want those, even for free.
Your video only reinforced that belief ;)

Thanks!  :-+
 

Offline Horstelin

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #281 on: February 09, 2015, 12:20:26 pm »
This is really interseting:
I have the UT61E which you are showing towards the end of the video. Mine is only rated 300V CAT III and not 600V CAT IV.
Despite that mine has a better input protection: A bigger HRC fuse for the 10 amps (690V, I1=80kA), 4 MOVs, and 3 PTCs.

Here are the photos of my UT61E:
https://dl.dropboxusercontent.com/u/11083462/DSCN1240.JPG
https://dl.dropboxusercontent.com/u/11083462/DSCN1241.JPG

My UT61D (which I bought from Reichelt.de) seems to have the same input protection:



At least the GS and TÜV logos they print on there seem to be real

Cheers
 

Offline mullecy

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #282 on: February 09, 2015, 12:38:57 pm »
In terms of specs the vc870 seems close to the Uni-T UT71E but seems better constructed:
https://www.eevblog.com/forum/testgear/conrad-voltcraft-vc870/
 

Offline Wytnucls

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #283 on: February 09, 2015, 01:21:53 pm »
Safer, yes. A lot of features are lacking: No AC+DC, 1kHz AC bandwidth only, 0.1% accuracy instead of 0.025%, no internal memory, optional PC connection, no peak hold and no current input jack aural warning.
Still, a pretty good meter.
 

Offline mullecy

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #284 on: February 09, 2015, 01:36:53 pm »
Safer, yes. A lot of features are lacking: No AC+DC, 1kHz AC bandwidth only, 0.1% accuracy instead of 0.025%, no internal memory, optional PC connection, no peak hold and no current input jack aural warning.
Still, a pretty good meter.

not really: it has true-rms, pc connection, and warnings if your probes are not in the right connectors...
if you want 0.025% and true rms ac+dc, take the vc880 for 30E more (but no W measure)

I don't say it's the best dmm but It's OK for lots of usages.
Which dmm would you buy for less than 200E if you had to choose one ?
« Last Edit: February 09, 2015, 02:58:53 pm by mullecy »
 

Offline Pasky

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #285 on: February 09, 2015, 02:28:57 pm »
I think that's the first time I've seen someone recommend a VC model multimeter over something else.   :P

EDIT: Nevermind, had no idea that was a Voltcraft.  Thought it was the cheap Chinese Vichy (sp?) multimeter.
 

Offline Wytnucls

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #286 on: February 09, 2015, 02:40:50 pm »
Safer, yes. A lot of features are lacking: No AC+DC, 1kHz AC bandwidth only, 0.1% accuracy instead of 0.025%, no internal memory, optional PC connection, no peak hold and no current input jack aural warning.
Still, a pretty good meter.

not really: it has true-rms, pc connection, and warnings if your probes are not in the right connectors...
if you want 0.025%, take the vc880 for 30E more (but no W measure)

I don't say it's the best dmm but It's OK for lots of usages.
Which dmm would you buy for less than 200E if you had to choose one ?
Assuming you live in Europe, a second-hand Gossen 26S, which I did buy. An 18S would be pretty good too.
The Fluke 185 is my favorite, but they don't come up for sale very often.
Incidentally, the VC870 and 880 have the same blind spot as the 71E on AC current.
« Last Edit: February 09, 2015, 02:51:38 pm by Wytnucls »
 

Offline mullecy

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #287 on: February 09, 2015, 03:28:17 pm »
Fluke 185 and 2nd hand meters... not easy to find...  :-//

I updated my reply: 880 has truerms ac+dc and has better accuracy and frequency response (1kHz 0.5%, 10kHz 1%, 100kHz 5%, instead of 1kHz 1% for the 870)... I start to feel that I should have bought this one instead of 870...

The problem is to have good performance, availability (if you can't actually buy it?) but also safety : what good is a 200E meter if you can't even check mains with it? At that price point, a bad input protection is unacceptable and raise the question of designers professionalism and the brand honesty: who really verify that the meter actually meets ALL announced performances ? (verifying VDC is easy but doing it ALL is a lot of work that 99.99% users will skip)
 

Offline janaf

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #288 on: February 09, 2015, 03:49:33 pm »
Small detail that annoys me with the UNI-T meters is that COM terminal is marked with red color text. At least on my UT71D. I have seen the same on pics of other UNI-T models too.
my2C
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Offline Maister

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #289 on: February 09, 2015, 04:32:30 pm »
I have the UT61E which you are showing towards the end of the video. Mine is only rated 300V CAT III and not 600V CAT IV.
Despite that mine has a better input protection: A bigger HRC fuse for the 10 amps (690V, I1=80kA), 4 MOVs, and 3 PTCs.
Where did you buy it?

My girlfriend bought it from www.reichelt.de (Germany) :) (X-Mas present for me :) )
Electronics design engineer, living in Germany.
 

Offline TASK

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #290 on: February 09, 2015, 04:39:04 pm »
Hi.

Im new here. Im frequently watching EEVlog videos. And a just saw that video on Uni-T. Iam as "hobbyist" (hope its writed good: D) sometimes need multimeter. Because i collect old audiotechnics from our national Czechoslovakian firm TESLA. So few years ago i bought Uni-T UT39C for like 45$ something like that. And i just bring you my fotoreport, sorry for not so good quality, i shot it in fast time.

Album:
http://task-ava.rajce.idnes.cz/UNI-T_UT39C

Offline G7PSK

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #291 on: February 09, 2015, 04:41:02 pm »
I don't think that Amprobe are any better. I have a AM240  There is only one PTC on the input and that is for the Volts ohms low amps and resistance etc. the high amps (if you call 10 amps high) has nothing except the fuse. Amprobe are frequently sold as being made by Fluke which of course they are not it is just the same group holding.
The only saving grace is the cat rating is only claimed to be cat III 600V
 

Offline Wytnucls

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #292 on: February 09, 2015, 07:45:13 pm »
Just opened my UT61B bought for 58€ in a brick and mortar shop (40 less than the next cheapest: the Brymen i really wanted including postage) last northern hemisphere summer.
I seems to have the input protection and proper fusing. It's quite ok and well built for the price.
And if the 61B(GS) 200107-7 code mean that the PCB was designed then? If that's the case, they've been able to do so since at least 2001!
It looks like you have a GS version modified with the old original BS1362 fuses in place and all MOVs removed. Not good.

That opens up a few questions:
- Can I solder some on?
- What should be they be rated at?
- Should someone start a thread on "How to make your UT61 less crap for a couple of Euros" (by someone competent, I'm not).
Sorry, forgot about your questions. Yes you can and because it is a GS board, it is easy. Just find out the specs from someone who owns one. Usually 1KV MOVs unless in series.
 

Offline Rutger

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #293 on: February 09, 2015, 07:56:53 pm »
I would agree that this is a bad meter, here is why I think so;

1) The design engineer planned to put better components on the board, but Management told them to cut the cost and they had to compromise of safety and on accuracy.
What other compromises are hiding in this meter??
2) A meter in this price class should have precision resistors and not pots that can drift over time and start to corrode.
3) I bet you that the drift of this meter is terrible, with time & temp & moisture this meter will go out of spec really quick.
4) Lying about a rating is just dangerous and wrong and a lawsuit is waiting to happen.

 

Offline DanielS

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #294 on: February 09, 2015, 08:14:28 pm »
4) Lying about a rating is just dangerous and wrong and a lawsuit is waiting to happen.
But who are you going to sue? While I have little doubt lying about safety compliance could potentially lead to wrongful death or injury lawsuits in most civilized coutries, you cannot sue Uni-T directly since it has pretty much zero official presence outside China. You would have to sue the seller who probably happens to be just a random somebody who imported seemingly decent multimeters and sold them for a few quick bucks, like so many other cheap yet dangerous Chinese electronics.
 

Offline janaf

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #295 on: February 09, 2015, 08:24:13 pm »
In the EU, as far as I know, it's the First importer / seller of a CE marked product who carries the responsability for the CE marking. Now how you prove who's first? But it may be something to think of if you import and sell, as manufacturers in China seem to slap on CE marks on everything.
my2C
Jan
 

Offline Yago

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #296 on: February 09, 2015, 08:29:27 pm »
In the EU, as far as I know, it's the First importer / seller of a CE marked product who carries the responsability for the CE marking. Now how you prove who's first? But it may be something to think of if you import and sell, as manufacturers in China seem to slap on CE marks on everything.

In UK, manufacturer or seller.
So Maplins could be in the firing line!
 

Offline Tepe

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #297 on: February 09, 2015, 08:34:03 pm »
Where did you buy it?

My girlfriend bought it from www.reichelt.de (Germany) :) (X-Mas present for me :) )
I had a hunch that it was from Reichelt. I wonder if they are the only ones selling these GS + TÜV marked meters or if other German shops also have them. Or put another way: Are they a special version made for Reichelt? I also wonder why they aren't branded differently or at least as another series to differentiate them from the lesser versions.
 

Offline Wytnucls

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #298 on: February 09, 2015, 08:36:52 pm »
I would agree that this is a bad meter, here is why I think so;

1) The design engineer planned to put better components on the board, but Management told them to cut the cost and they had to compromise of safety and on accuracy.
What other compromises are hiding in this meter??
2) A meter in this price class should have precision resistors and not pots that can drift over time and start to corrode.
3) I bet you that the drift of this meter is terrible, with time & temp & moisture this meter will go out of spec really quick.
4) Lying about a rating is just dangerous and wrong and a lawsuit is waiting to happen.
1. Possibly
2. It has precision resistors.
3. Hardly any drift over 2 years of monitoring (71D and 71B bench use).
4. The glass fuse version can't be sold in Europe anymore. If UNI-T has provided papers to EU importers documenting compliance with IEC regulations, the importer is not liable, unless the meters carry the importer's label.
To sue or report the meter as unsafe, the best way would be to point out the creepage distances below the required 8mm for CAT III 1000V.
« Last Edit: February 09, 2015, 08:47:43 pm by Wytnucls »
 

Offline rob77

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Re: EEVblog #712 - Uni-T UT71E Multimeter (Why Uni-T Meters Suck)
« Reply #299 on: February 09, 2015, 10:55:27 pm »
Safer, yes. A lot of features are lacking: No AC+DC, 1kHz AC bandwidth only, 0.1% accuracy instead of 0.025%, no internal memory, optional PC connection, no peak hold and no current input jack aural warning.
Still, a pretty good meter.

not really: it has true-rms, pc connection, and warnings if your probes are not in the right connectors...
if you want 0.025% and true rms ac+dc, take the vc880 for 30E more (but no W measure)

I don't say it's the best dmm but It's OK for lots of usages.
Which dmm would you buy for less than 200E if you had to choose one ?

I bought the Brymen 869s  : 0.02% on low DC voltage ranges, true rms, AC + dc, very fast continuity tester (fastest i ever had) , and it has proper input protection (photo posted earlier in this hread) . it was 210Euro including 20% VAT (bought from TME).
 


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