Review and tear-down of UNI-T UT612 LCR meter

[Nuno_pt]

At $120 it's not a better choice the DER EE DE-5000, it has 100KHz?

If we need the 100KHz on the Applent you need to get the AT-826A, not the 825A, that's a jump from $180 to $230, about $100 more than the DE-5000, but the Applent have proper 4 wire measurement.

[Wytnucls]

The cheapest 826 I can find on eBay costs 330$ + postage:
http://www.ebay.com/itm/NEW-APPLENT-AT826-Handheld-LCR-Digital-Meter-Electric-Bridge-100Hz-100kHz-/290931633508?pt=LH_DefaultDomain_0&hash=item43bce06d64

The cheapest 825 goes for 190$ + postage:
http://www.ebay.com/itm/APPLENT-AT825-Handheld-LCR-Digital-Meter-Electric-Bridge-100Hz-120Hz-1kHz-10kHz-/121127135336?pt=LH_DefaultDomain_0&hash=item1c33bd6868

Prices are even worse on Amazon.

The DER EE DE-5000 (full set) sells for 184$ with free postage:
http://www.ebay.com/itm/DER-EE-DE-5000-Fullset-High-Accuracy-Handheld-LCR-Meter-TL-21-22-23-IR-AC-DC-/161418672697?pt=LH_DefaultDomain_0&hash=item25954d7a39

[Nuno_pt]

Wytnucls, your right I was looking at euro prices.

[MCCSolutions]

AFAIK, the UT612 was never advertised as being equipped with a Kelvin connection. The tweezers provided are shielded though and so are the UNI-T clips sold on the internet. Some unscrupulous sellers advertised them as Kelvin, but if you know your meter, it is easy to tell that it has no 4 wire connections: The middle jacks are clearly marked 'Guard'.

The peculiar LCD screen has been discussed at length. The CEM LCR meter screen is just the same. I really don't think it matters that much, but I understand that some people may be unhappy with it.

I see that some UT612 are available for 120$ or less on eBay now, with free shipping:
http://www.ebay.com/itm/UNI-T-UT612-Multi-purpose-LCR-Meter-Inductance-Capacitance-L-C-R-DCR-Q-D-ESR-/221392747637?pt=LH_DefaultDomain_0&hash=item338c093c75

And yours of course, with the Kelvin clips  :
http://www.ebay.com/itm/Uni-T-UT612-digital-LCR-meter-/171457846139?pt=LH_DefaultDomain_0&hash=item27ebaf1b7b

Wow this took off in a day. Its funny because after doing research since the last time I posted I also came to the conclusion to buy the AT825, especially after the video review. I like the Auto and A-B Feature. But I do get what your saying, although cant it share the common Guard and get the relative 4 points of measure as shown in action in the video?, Is the UT612 not just the same?(PIC BELOW) Unless something better comes out I will be buying the AT825 and the UT612(I have a all RED and Black EL Lab  )

[Wytnucls]

The 612 could be modified fairly easily for 4W measurements, but I don't think it's worth the effort, unless that would be your only means of Kelvin measurements or you're bored and are looking for a mod challenge.

[HiTech]

Wytnucls --- that's not my Uni-T meter up for sale --- mine was sold awhile back. Don't rush to assume things.

BTW, Ali Baba has the lowest price for the Applent AT825  It just depends who you contact for a quote..... some vendors even include a copy of the manual in print rather than having to d/l it off the net.  If I recall correctly, a friend of mine bought his for under $180 and that included e-packaging from China and a printed manual.

[Wytnucls]

Wow, what a coincidence...the only UT612 for sale in the US with Kelvin clips and it's not yours. And guess what...he's also selling a Datron 1065A just like yours. Sure you don't have a twin brother? Never mind.
Enjoy the Applent. It's good that it comes with a hard copy of the manual like the meters from Agilent. and I hope it also comes with a magnifying glass to decipher those small fonts. 

[MarkPalmer]

Modern day manufacturers, especially those operating out of the orient, have it down to a science with very few exceptions to the rule.  You are going to get what you pay for.  You can see in my picture of the Applent AT825 circuitry that quite a bit more goes in to it by comparison to the Uni-T LCR, and that in a nutshell is why it costs more.
 
I should have been clear in my previous post about the Uni-T 100 kHz ranges.  The number of ranges isn’t necessarily limited, but the values of capacitors and inductors it can test at 100 kHz are limited to values to where the comparison of the measurements between 10 and 100 kHz would be very negligible, but perhaps of some concern depending on the applications the LCR is used for. This is the same with true 4 wire ohms measurement values.  With an LCR it might matter to some, for others 4 wire testing might not be a critical factor.  Still, my feeling is it’s a feature every LCR meter should include as a precision resistance measurement tool.  Perhaps all LCR’s should have the 100 kHz test frequency be useable at all maximum values in the specifications, but this is where it can get confusing and is a big reason why LCR’s step up steeply in price depending on the usefulness of the LCR at 100 kHz and the values of components it can test at that frequency.
 
I think a lot of audiophile types see a low priced LCR with the 100 kHz test frequency and think hey, wow, I can test the values of all my esoteric audio E-Caps at a response up to 100 kHz!  Cool!  The problem is they don’t really look at the specs before buying to see what the capacitor value limits are- they will likely be disappointed in this figure on a low priced LCR that features a 100 kHz test frequency.  It’s sort of the same scenario in that the number of megapixels a digital camera has doesn’t necessarily mean it will take the highest quality of digital photos, but putting the high figure there makes for a more impressive selling point. You really have to look at what it is you are getting for the money.

AT825 internals:


-Mark-
 

[Wytnucls]

I have some trouble understanding why an LCR meter consisting of a bunch of tightly packed opamps, transistors and discrete components would be any better than a couple of properly developed and time tested ICs with just a few supporting components around them. After all, that's the way the industry is moving forward, probably at a lower cost, but mostly for higher reliability.

Should your Applent meter fail after the 1-year warranty period, you will have to throw it away and buy another one. If someone fries one of the ICs on any the Cyrustek-equipped meters, there is a good chance that the company will send replacement components on request for free, as reported by one of the members here, just a few months ago.

4W resistance measurement capability is quite rare on a portable 4 1/2 digits instrument, but very common on bench meters with much higher counts and accuracy. Tellingly, the published accuracy for the Applent isn't that great on the 5 Ohm range (1%+3) compared to the 612 20 Ohm range (1%+5).

[HiTech]

It’s sort of the same scenario in that the number of megapixels a digital camera has doesn’t necessarily mean it will take the highest quality of digital photos, but putting the high figure there makes for a more impressive selling point. You really have to look at what it is you are getting for the money.

-Mark-

True - there are many older digital SLR cameras of 4-5 megapixels with quality glass optics that take better images overall than 12+ megapixels using plastic aspherical lenses.

Question:  is that foggy area on the pcb of the 825 caused from the camera flash? It almost resembles a part(s) that smoked!

[HiTech]

Enjoy the Applent. It's good that it comes with a hard copy of the manual like the meters from Agilent. and I hope it also comes with a magnifying glass to decipher those small fonts. 

The UT612 has it's share of small fonts also. Realize that the Applent's display is a bright, contrasting colors TFT, so distinguishing the fonts is rather easy compared to that of a monochrome lcd display..... worse yet, one that is on the faded side.

Let's not forget the title to this thread is: Review and tear-down of UNI-T UT612 LCR meter  Your review of the meter is informative; I was just reporting my view, having owned one, and more from the standpoint of its value per dollar spent. Yes it seems to meet a targeted point of sale with it's low price tag. I view the Applent 824/825 models to be products that affordably bridge the price/performance gap between the lower cost LCR meters and the high cost units.

[MarkPalmer]

It’s sort of the same scenario in that the number of megapixels a digital camera has doesn’t necessarily mean it will take the highest quality of digital photos, but putting the high figure there makes for a more impressive selling point. You really have to look at what it is you are getting for the money.

-Mark-

True - there are many older digital SLR cameras of 4-5 megapixels with quality glass optics that take better images overall than 12+ megapixels using plastic aspherical lenses.

Question:  is that foggy area on the pcb of the 825 caused from the camera flash? It almost resembles a part(s) that smoked!

Yes, I did blow it up. I just decided to take the photo before I toss the little piece of junk in to the trash.      Yes, it's the camera flash.  Irony as I mention pictures from digital cameras earlier. 

Take a look at the other products Applent produces, and their other higher end LCR's.  You will notice the company isn't in to the $3.00 throw-away multimeter market.  I’m fairly safe in saying Applent’s designers could put the entire handheld LCR circuit on a few chips if they wanted to design them that way.  But rather than do that, they picked much of their handheld LCR circuitry and features from their more upscale models.  Things are done a certain way for reasons, even things as simple as protection diodes that cost a little extra in production. If that were false, the LCR’s from industry leader Agilent would look like a Uni-T inside also- which they don’t. 

The made in China point is moot when or if it comes to service .  Will I have to throw the Applent away if it fails out of warranty?  That I don't know for sure.  I also wouldn't know that answer for sure if I owned a Uni-T.  Time will tell all, that is why I did the thread on the AT825.  My intent isn't to steal this thread, only to show how another example of an LCR in this same price range is made and/or how it differs.  I did notice from earlier reading here at EEVBlog that Uni-T is sort of leading the way in the Multimeters that do not appear to meet their safety specs thread though, which is not uncommon to things made with the most cost-cutting at the heart of the design.     
 
-Mark-

 

[MCCSolutions]

It’s sort of the same scenario in that the number of megapixels a digital camera has doesn’t necessarily mean it will take the highest quality of digital photos, but putting the high figure there makes for a more impressive selling point. You really have to look at what it is you are getting for the money.

-Mark-

True - there are many older digital SLR cameras of 4-5 megapixels with quality glass optics that take better images overall than 12+ megapixels using plastic aspherical lenses.

Question:  is that foggy area on the pcb of the 825 caused from the camera flash? It almost resembles a part(s) that smoked!

Yes, I did blow it up. I just decided to take the photo before I toss the little piece of junk in to the trash.      Yes, it's the camera flash.  Irony as I mention pictures from digital cameras earlier. 

Take a look at the other products Applent produces, and their other higher end LCR's.  You will notice the company isn't in to the $3.00 throw-away multimeter market.  I’m fairly safe in saying Applent’s designers could put the entire handheld LCR circuit on a few chips if they wanted to design them that way.  But rather than do that, they picked much of their handheld LCR circuitry and features from their more upscale models.  Things are done a certain way for reasons, even things as simple as protection diodes that cost a little extra in production. If that were false, the LCR’s from industry leader Agilent would look like a Uni-T inside also- which they don’t. 

The made in China point is moot when or if it comes to service .  Will I have to throw the Applent away if it fails out of warranty?  That I don't know for sure.  I also wouldn't know that answer for sure if I owned a Uni-T.  Time will tell all, that is why I did the thread on the AT825.  My intent isn't to steal this thread, only to show how another example of an LCR in this same price range is made and/or how it differs.  I did notice from earlier reading here at EEVBlog that Uni-T is sort of leading the way in the Multimeters that do not appear to meet their safety specs thread though, which is not uncommon to things made with the most cost-cutting at the heart of the design.     
 
-Mark-

Hey hey hey wait now, I would be more than happy to buy that toasted one off of you for spare parts! 

Also how did you toast it in the first place?

Also the Chinese manufacturers are not all bad, Japan either. As a matter of fact the beloved Fluke and other brands are also made there 

Now speaking from experience in import, export, and wholesale, the actual manufacturers are good at making their customers happy. The problem is the middle men, the drop shippers and suppliers that you all deal with, they are NOT a reflection of the company. For many manufacturers they are working their way up and do not have a robust customer service department that speaks various languages, thats why they choose to only freight to resalers and suppliers. I have found that it is fairly easy to get what you need when you need it via DHL in 3 days from China if you talk to the right person!!! 

[HiTech]

MCCSolutions - I think you missed the part where M. Palmer said the smokey appearance is due to the camera's flash reflecting off the pcb.

[MCCSolutions]

MCCSolutions - I think you missed the part where M. Palmer said the smokey appearance is due to the camera's flash reflecting off the pcb.

Yea I know, I think he was being sarcastic but you never know lol 

[papabol_24]

Hello, joined this forum to say thanks to all who posted photos of this lcr meter, I screwed mine today by accendentally putting 120vac on the inputs (long story)... I managed to repair it with the help of the photos posted here, 3 smd input resistors R1, R11, R10 where burned and chared, replaced them and crossed my fingers and yes!!! Got it working again, thanks guys...

[Chupacabras]

Good review. It's already a few years ago from now.
But do actual batches have the same weakness in LCD display? I mean that viewing angle.

[leonerd]

Anyone managed a successful 4wire mod on this? Looking at those PCB traces it does look eminently doable.

I'd be more interested in that than the guard - I regularly want to measure resistances below 1ohm, whereas I don't think I've ever cared about anything bigger than 100k, let alone a meg. Having 4 wire would definitely count more than guard, so I think I'd just repurpose those two guard sockets into 4wire mode instead.

[Pr0metheus]

Dissipation Factor (tan D) max values chart.
Update 18May2017

[Pr0metheus]

Added more capacitors + LoadLife values

[Wytnucls]

Thanks Pr0metheus.
Useful table f0r tr0ublesh00ting. 

[seasalt]

Great review, was thinking about getting one and after the review I'm going for one.

[rauldm]

In conclusion, really matter the 4W of DE-5000? really has more accuracy than UT612? DE-5000 is not comes with 4W probes, in my country the price difference between DE-5000 and ut612 is around 30 usd more for DE-5000, but ut612 comes with all accesorys and case. The 4W improves accuracy only on DC resistance test? I have a 4W bench meter with this  function.

[Bad_Driver]

After going through different boards here to get a better understanding of this LCR thing I decided for a brand new UNI-T UT612.

Thanks for all the efforts and advices in this board during the last years. In the beginning I considered a DE 5000, but after reading the tests of Wytnucles
and the long Youtube video of DefProm I go now with the UT. It seems to have the same chip set but looks much fresher ;-) than the DE-5000. (btw: the DE-5000 is till now only available
via direct import from Japan or the USA, the risk of import taxes is given)

The UT612 is a big improvement over my old Atmega based 10€ LCR meter! For my hobby needs it should be ok.

I don't have any planning to run a calibration shop  (as some others when I read the postings here)

Since I own a decent DMM (34401A) with Kelvin clamps for R (as many others I'm sure, no one buys a LCR meter as first device) I do not really care about the wide and broad  discussed
pros and cons of 4W measurements with all the named devices.

It came as described in a plastic box and all the adaptors and cables. Build quality is good for that price point (130€) and it came from a german reseller. (PinSonne Elektronik)
It has a good LCD screen now (2020). The earlier (years ago) mentioned weaknesses of it are not noticeable.

It does the job!
Thanks again for all the efforts, tips and hints here!

[fkfaraz]

post the pic man

also pic of lcd too..