UNI-T UT61E Multimeter teardown photos.

[hans_ober]

The EU version is also sold by committed chinese vendors on Alibaba and Aliexpress but that's none of my business 

Is it? I've tried searching aliexpress for "ut61e gs" and "ut61e eu" but never found anything.

[analogix]

I also didn't find the European "GS" version on any of those Chinese sites (or perhaps I did but didn't trust if that was really true. Actually I believe I did find a "GS" version pictured somewhere, but asked and it turned out to be the wrong photo, meaning they sold the Chinese version anyway), assuming it's not possible for Chinese dealers to get it through the usual channels.
I ended up buying mine from Reichelt in Germany. Haven't opened it up yet though.

[Fungus]

I didn't know Uni-T made desktop meters. They're cute

Update:

a) I saw a picture of one in context, they're not cute at all, they're massive.     

b) I also saw a pic of what's inside. The oversized case is mostly filled with marketing:



Should we or should we  ?

[dinoboy]

assuming it's not possible for Chinese dealers to get it through the usual channels.

Sorry i confused Aliexpress with Alibaba .

Believe me, UNI-T factory sales reps are more than willing to sell their products at MOQ to any (serious) Chinese or non-Chinese company at MOQ, such as wholesalers or trading companies or importers. Vely small Aliexpress businesses or private individuals wouldn't be able to buy from UNI-T factory direct. I've got a quote from a "Manufacturer, Trading Company (Total Employees: 51 - 100 People)" on Alibaba who quotes the following prices no matter who you are (b2b client, international importer, local retailer, end consumer, or small business):

1000pcs UT61E Normal version - 35.0US$ Fob China port
1000pcs UT61E German version (TÜV/GS) - 57.0US$ Fob China port

So these are pretty much the lowest prices, if you (individual or business) go through a Chinese middleman. However I don't believe that Reichelt goes through any trading company but purchases their UNI-T stuff at MOQ off the UNI-T factory direct. At the same time I have reason to believe that the quote includes a rather low margin for that Alibaba Chinese trading company; exfac prices could be 20% lower, please don't quote me on that:
1000pcs UT61E Normal version - 28.0US$ exfac *my guess*
1000pcs UT61E German version (TÜV/GS) - 45.6US$ exfac *my guess*

The jump from 45.6$ to 85€ (Reichelt) is steep .. and my neighbor accepted it 

[001]

Huh-huh 

UT61E invented about 10 years ago

What new about nowday substitutions?

[Nawual]

After i have read 41 pages...ummm...where can i buy the versión gs with a good price?.Thanks

[Rango]

Slap the 3 low capacitance MOV units in, and be done with it. The limiting factor will be the PTC in any case, 1kV and it will fry itself apart in a second or so. Choose the voltage to suit your normal use, and as they mostly come from RS in packs of 10 you will have some spares. If you do blow them up the meter will not survive in any case.

In my case I just used 2 275V MOV units ( 7mm) in series, as I did have the remains of a 10 pack around, so using the 6 was easier than either placing an order and wait till I had the minimum order price in other parts, or paying the $20 courier charge RS puts on here for small orders. Still have 1 left, after replacing 3 MOV units on other equipment.

@SeanB so reading threw last 20 pages i gathered that slapping those 3 movs it would increased chances of input protection. Why 3 not 4 or 2? Which spots GS1 threw GS4 ? If only 2 then which spots? Wouldn't this 30pF Vishay Vishay VDRS - E Series Metal Oxide Varistor 30pF 5A, Clamping 1200V, Varistor 750V (178-059) be best option as it has lowest capacitance rating hence not throwing up capacitance rating too much out of calibration on 61e when measuring capacitance as compared to other once listed below? Would this affect any other measurement readings and to what degree will it effect capacitance rating? Also those come in pack of 5 so would also be ideal unlike pack of 10?

Does anyone know what those original green Mov's part numbers are on GS version PCB or would those movs listed below be better since their rating is higher for voltage? What about fuses replacement/upgrade/Siba? Would that effect mA readings for example?

It seems latest PCB versions of 61e are same as GS so it looks like installing those Movs would make this GS DMM minus 10A trimmer? Why is that trimmer missing and what effect having the trimmer in CHI version have with those movs do?

"it seems that the PCB is the same between the world-wide and German versions today, but I've not been able to verify that - the photos I've seen of the German PCB seem to be missing the 10A trimmer (by the 10A fuse, between the input sockets), amongst other differences.

There are a lot of beefy SMT diodes, which I presume are also for protection. We have a single IR LED for the PC interface, with a 4069 CMOS hex inverter next to it. Under the screen is the divider resistor network - I've not removed the screen to investigate further, but it appears to be encapsulated in plastic, so I can't tell if it's a nice thick-film network like Fluke use (as if it would be!). As with the UT210E, the crystal is 3.999MHz rather than the usual 4MHz."

https://www.markhennessy.co.uk/budget_multimeters/unit_ut61e.htm

If anyone else would like to jump in and help me out that would be greatly appreciated.

Any other Parts besides green movs that appear on GS PCB board that could be modded into CHI PCB board to reflect original GS design?

Here are the mov parts i gathered that can be used in GS1-GS4 spots

http://uk.rs-online.com/web/p/metal-oxide-varistors/0178059/?searchTerm=178059&relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B362C377D7C5C647B31307D7C28283F69292852537C5253207C52532D293F5C647B337D285C73293F5B5C732D2F255C2E2C5D285C73293F5C647B332C347D292426706F3D3126736E3D592673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D313738303539267374613D3031373830353926

https://www.mouser.com/ProductDetail/Bourns/MOV-07D681K/?qs=lgttKnAd%252b2CCDLVYA77ICw%3D%3D

http://uk.rs-online.com/web/p/metal-oxide-varistors/7606964/?searchTerm=7606964&relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B362C377D7C5C647B31307D7C28283F69292852537C5253207C52532D293F5C647B337D285C73293F5B5C732D2F255C2E2C5D285C73293F5C647B332C347D292426706F3D3126736E3D592673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D37363036393634267374613D3736303639363426

http://uk.rs-online.com/web/p/metal-oxide-varistors/7118149/?searchTerm=7118149&relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B362C377D7C5C647B31307D7C28283F69292852537C5253207C52532D293F5C647B337D285C73293F5B5C732D2F255C2E2C5D285C73293F5C647B332C347D292426706F3D3126736E3D592673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D37313138313439267374613D3731313831343926

http://uk.rs-online.com/web/p/metal-oxide-varistors/2897109/?searchTerm=2897109&relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B362C377D7C5C647B31307D7C28283F69292852537C5253207C52532D293F5C647B337D285C73293F5B5C732D2F255C2E2C5D285C73293F5C647B332C347D292426706F3D3126736E3D592673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D32383937313039267374613D3238393731303926

This one does not state capacity rating anywhere
https://www.tme.eu/gb/details/siov-s20k625/tht-varistors/epcos/b72220s0621k101/

Here is an idea how about we open up fund me page for joe smith and each of us fund few $ to buy 61e and just add movs and put it threw his test without any other board modifications (cutting pcb lines and other stuff he did)? That way we know if it survives input protection of not and no one has to sacrifice it's meter and cost to each of us would be $2-4. 

Pic attached Not mine UT61e GS PCB board

[Rango]

I picked up a brand new UT61E.   It appears identical to the one 5KY had sent.   Metal can and all.   

So, what I would like to do if modify this meter with the MOVs people are recommending, or use the parts that are available in the one being supplied to Germany.   I will then retest it to failure and see if there are any improvements. 

Keep in mind the 61E and D never made it to the mini surge test.  They both failed ESD with that little grill starter.

@joesmith did you ever mod chi 61e with only movs seen in GS version (which btw is also same movs as in your 181A i think) to see if it survived ESD test and maybe up 1000V test? Basically that would be my goal with movs and fuses upgrade. I'm not sure why 1000v fuses are so damn expensive. It's just a wire inside isn't?

I see Holdpeak 35$ meter pretty much survived almost all of your test. Makes you go hmmm.

[racemaniac]

I recently also received a UT61E from china, seems like a fun device.
bought it since i wanted something basic that could log data.

One issue i had with mine when it arrived was a few segments of the LCD not lighting up properly (you could only see them light up when looking at an angle) (which luckily meant the signal was there, and the segments weren't broken ).
Googled a bit and found videos of people cleaning the pads on fluke multimeter pcb's that connect to the lcd. Opened up my ut61e, and i saw the same style of pads, and a few were very clearly dirty, cleaned them up with a q-tip with some acetone on it, and the lcd is now showing perfectly .

[Nisei]

GS model and regular model next to eachother.

[wasyoungonce]

Urggh

My UT61E is again out of calibration, see here: 
https://www.eevblog.com/forum/testgear/how-good-is-the-ut61-series/msg1214739/#msg1214739

Was measuring 12V it read around 10.2V. Its done this before.  I don't have the PCB ver and spare pads to install an LT1970 Vref...although I could do it.  But that's not the issue...it keeps going out of cal by quite a bit.  Any suggestions?  Maybe I should first change the POT I mean there is not much to go wrong here looking at the schematic.

An unreliable multimeter is useless..so I have to fix it.  Using one of my many backuo meters atm

Brendan

[evgen.05]

Urggh

My UT61E is again out of calibration, see here: 
https://www.eevblog.com/forum/testgear/how-good-is-the-ut61-series/msg1214739/#msg1214739

Was measuring 12V it read around 10.2V. Its done this before.  I don't have the PCB ver and spare pads to install an LT1970 Vref...although I could do it.  But that's not the issue...it keeps going out of cal by quite a bit.  Any suggestions?  Maybe I should first change the POT I mean there is not much to go wrong here looking at the schematic.

An unreliable multimeter is useless..so I have to fix it.  Using one of my many backuo meters atm

Brendan

Blue trimmer VR1 - is bullshit. I have the same problem. Replace and calibrate it - and calibration will never goes out.

[wasyoungonce]

Blue trimmer VR1 - is bullshit. I have the same problem. Replace and calibrate it - and calibration will never goes out.

Many thanks I'll do that and post back.

Brendan

edit:
Pot ordered.

[Stinger]

Hello,

No 2018 version of UT61E with backlight ? 

[wasyoungonce]

Ok re: my UT61E was loosing cal and was all over the place DC volts.  Put in new 2K pot adjusted roughly with variable PSU...its all appears ok time will tell.  Waiting for cheap fleabay voltage reference to arrive to cal it better.

https://www.ebay.com.au/itm/262940287208

Yes I know they are not that great but its good enough for me.

I'll post back when I get it an re-cal. Thanks to all.
Brendan

[wasyoungonce]

Ok meter Cal was all over the place...replace 2K POT dud rough Cal to variable PSU now have Cheap Chinese voltage std AD584KH, on ref IC, says AD584-M on plastic case.
Here.  Has inbuilt battery and odd USB recharge connector.  Sigh I hate that but I couldn't build it for that price ~ $20 Aud.

Didn't come with any Cal info. 

Anyway my UT61E wasn'yt out much and is behaving much better since the Pot change, no wild changes in calibration.  I did tweak the Cal a little, its all good.  Now I want a Resistance std...probably just get some precision resistors.  I think I'm just been bitten by the bug!  Oh my older multimeters are shall we say..."in need of calibration"

Many thanks to the forum members for help.

[escape]

Chinese vs EU version differences aside, are there any counterfeit/knockoff UT61Es out there?  If so, how can you tell it's a knockoff?

I'm seeing a bunch of them on US ebay for under $35 (including free shipping from within US), and wondering why the price is so low.  I'm guessing they don't carry official Uni-T warranty.

[escape]

Didn't come with any Cal info. 

Without actual calibration info against a known reference meter, that AD584 box is fairly useless.  It should have come with actual reference values printed on a sticker attached to the bottom of that AD584 rig.  Mine looks like this:



Of course there is some controversy as to whether these sticker values are actual measured values or just some random numbers that someone made up or copied from another sticker.   

[Stinger]

We believe a F version with factory backlight and ESR mesurement. 

[joeqsmith]

Didn't come with any Cal info. 

Without actual calibration info against a known reference meter, that AD584 box is fairly useless.  It should have come with actual reference values printed on a sticker attached to the bottom of that AD584 rig.  Mine looks like this:



Of course there is some controversy as to whether these sticker values are actual measured values or just some random numbers that someone made up or copied from another sticker.   

Even with the sticker, and even if they did correctly copy it from some random HP34401A, you have no idea if the meter they checked it against was even in current cal.   You could have the standard sent in and get a NIST traceable report for it but it may cost far more than the little device cost.   

[DiddlyJackSquat]

One of my mates blew up his UT61E that i sold him 

idk how he blew it exactly as details are scarce but he told me he blew it in current mode measuring a lipo in current, with the 10A ports and I told big fat bad idea... Now all readings are off.

I'm getting it later from him so i might be able assess the damage

[escape]

Speaking of blow ups, I had a major brain fart yesterday... I had my UT61E in "A" position, test leads connected to COM and 10A sockets.  One test lead was connected to negative terminal of a fully charged 12V car battery, and then I attempted to touch the positive battery terminal with the other test lead.  I only touched the positive terminal for a split second since I saw a spark at the positive terminal and heard the DMM beep.

The DMM still measures voltage, but not current on the 10A socket.  Hopefully I only blew the fuse and nothing else.  Is BS1362 the correct replacement fuse?  I have the Chinese version, not the German version.

Thanks!

[DiddlyJackSquat]

Speaking of blow ups, I had a major brain fart yesterday... I had my UT61E in "A" position, test leads connected to COM and 10A sockets.  One test lead was connected to negative terminal of a fully charged 12V car battery, and then I attempted to touch the positive battery terminal with the other test lead.  I only touched the positive terminal for a split second since I saw a spark at the positive terminal and heard the DMM beep.

The DMM still measures voltage, but not current on the 10A socket.  Hopefully I only blew the fuse and nothing else.  Is BS1362 the correct replacement fuse?  I have the Chinese version, not the German version.

Thanks!

Yes, BS1362 is the correct replacement fuse.

[wasyoungonce]

To member "Sonny"....you PM'd me but I cannt reply as your post box is full....

So I'll post here and hope you notice as it was wrt to this thread.....

Sorry for the late response...I've been in hospital for last 6 weeks...yet another spinal fusion (I've had quite a few lumber and cervical).   This one worked very well but I've been spending some times on drugs and on the net...a dangerous combination.....

Anyway as for the PCB ver...I think I posted pics but am looking for them...or I'll tear it apart when I can.

Pot I used was 2K , 785-9828 RS mrn.  785-9828

Its a 3296Z Bourns pot, 2K 10% +/-100PPM/C, so yeah could have done better here!   I think it was what I could get at the time!.  Another Problem is its centre legs is offset so I had a bit of bending to do prior to fitting...

I'll do pics soon ummm it didn't have pads to vref IC!

Oh yeah its kept cal ever since changing the pot!

Brendan

edit:
Jeez Sonny your postbox is still full....I cannot PM back to you till ya empty !
And correct pot should have been Bourns 3296x pot as these pins are inline pins and its side adjust or 3296W for a top adj pot.  I'm sure top adj will fit ok. The RS 3296X pot is RS number: 521-9912, mfgr mrn: 3296X-1-202LF, RS cost $4.30 ea.

 

[sonny]

Jeez Sonny your postbox is still full....I cannot PM back to you till ya empty !

Hello,
Thanks for your post. My postbox is 340% full, I suppose Dave did another shrink to the accounts some time ago. I removed 15 messages and my inbox is still full. Do you know where are the requirements for the accounts, because I can't find them.

I hope you are doing well now after your spinal fusion?

I also noticed that it's not Bourns 3296Z, because of the pins alignment. Bourns 3296X seems to be the best choice. I measured the pot in my UT61E and it shows around 500 ohms. I think 3296X with 1k will be the perfect fit and it will provide better resolution for the calibration.
Regards,