EEVblog #712 – Uni-T UT71E Multimeter (Why Uni-T Meters Suck)


Dave shows why Uni-T multimeters generally suck in this teardown (and a little bit of a review) of the $180 UT71E 0.025% accuracy multimeter with power measurement capability.
He also opens the UT71A, UT61E, and compares the input protection and rating with a Brymen BM257.

MAX6190 Voltage Reference
OP1177 Opamp
Cyrustek ES51922 DMM chipset
Holtek HT1621 LCD driver
AD636 True RMS Converter chip

Forum HERE

Hires teardown photos:

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    • Miguel Rodrigues

      Awh men! Just bought a T-UNIT UT61D just a week ago based on a previous review.
      It was the most affordable i could get… Anyway is still better than a cheapo chinese 5€ multimeter that I have…

      • Same here.. :/ Just bought the UT61E. I also had one of these cheapos here before. Fluke would be nice but a little too expensive for me as poor young hobbyist isn’t it?
        Watched this Review: https://www.youtube.com/watch?v=Bz6CYDRl1M8 and it didn’t look thaat bad. But yeah you get what you pay, hope it will do the job as far for the next few months until there is money for a fluke DMM.

        • Miguel Rodrigues

          I will only use it for low power small projects. In worst case scenario will use it to measure mains 220v voltage. At least I’m sure that will not blow my hand apart when measuring. Not the same thing for the Chinese meter.

          • Yeah i think they are both fine and i don’t usually work with the mains.
            Sometimes if i have an old audi amp that i want to repair or these things, then it can happen that i measure 230v but usually i us it for Logic Level measuring (Microcontrollers, audio stuff etc.)
            Actually i took the UT61E because of the better resolution but primary because it’s price was reduced the time i bought it. (Payed $50 bucks)
            As Dave said in one of his Multimeter Vid’s i think for frequency it’s better to use an osciloscope. The Mainreason for me was the better resolution and the higher capacity range (don’t know the capacity range of the UT61D, could be equal, i compared it with the UT61B which was my alternative for this price)

            Yep thats true i think it will do the job. The Fluke ones are way to expensive for me, especially the fluke meters with the same features of the UT61D/E.
            Did you got an UT61 with the Serial or with the USB Adapter? Just wondering, sadly i only got the serial adapter. Could buy the USB adapter but currently i don’t need this feature.

            • Miguel Rodrigues

              I got both! 😛

              Didn’t tried the serial cable, but with an USB to RS232 Adapter should do the job.

              The software doesn’t do much. The main useful functionality is to allow to port measurement data into the computer and save in an Excel file for posterior analysis.

              Also allows to see graphically the acquired data (value per record driven), setting high and low acquirement value limit and, of course, view the latest measurement on big chunky “7 segment” digits, the same way as the meter does.

    • wlinaz

      First RadioShack, now this… Dave you’ve ruined my week! 🙂

    • Nic Perrin

      If you cross out all the claims of Cat III/IV rating, and don’t subject it to anything over 230v, it’s a reasonably accurate high count meter for not many $$.. I’m concerned about the long term reliability of the cheapy trimmers though.. and although the 61E looks okay, I wouldn’t trust the 71 with anything over a couple of amps with that screw through the current input.

    • Chris

      Dave, have you ever given any thought to designing your own meter for fun? Would be interesting to see the thought you would put into the layout and the parts and what not.(if you have mentioned any of this in a previous video, well my memory is pretty good, but not photographic)

      • marineio

        What about a nice bench style DMM, rather than a handheld? Then everything can be bigger / through hole, make it easier for us young players 🙂

    • muki16

      180 bucks for this crap….unbelievable. You get a decent 2nd hand Fluke for half of that. Unity’s marign must be in the thousands of percents

    • Patrick

      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.

      https://dl.dropboxusercontent.com/u/11083462/DSCN1240.JPG

      https://dl.dropboxusercontent.com/u/11083462/DSCN1241.JPG

      • Hasitier

        Mine is looking exactely the same inside and is also labelled/rated as yours Patrick. Maybe they produce a better one for Germany to meet the GS label?
        I like mine and have it since a year or so. Maybe we should send Dave a German version of a UNI-T to change his mind? 😉

        • Patrick

          Yes, we schould definitely send him a good german one 🙂

      • Nic Perrin

        It looks a totally different layout than Dave’s. Yours has resistors around the diode bridge at the inputs, and an isolation slot routed in the board.. If they’d omitted components or changed for cheaper lower spec I’d have more confidence, but who knows which PCB layout you’re going to get.. You can add a better fuse and a mov or two, but you can’t change the board.

    • Mark Palmer

      For me, a multimeter that you have to question if you can trust it under certain circumstances that it’s supposedly rated for is totally worthless. And that’s Uni-T. I wouldn’t waste any amount of money on those worthless things. Invest in a Fluke, and you’ll never look back.

    • Boffin

      I suspect you don’t have a UNI-T, but a Chinese copy of a Chinese meter. Hence the mods to use cheaper fuses, bad trimmers etc etc.

    • ShirlCollison2

      Just awesome topic! Thanks for the info, super helpful. I just filled out DA 7223-1 with an online software. It looked much better typed than hand-written. I used http://goo.gl/Ggmjhy

      and it’s very easy to use.

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