A look at the Uni-T UT210E

[mos6502]

I hate Uni-Turd with a passion. But since I was looking for a cheap meter to throw in the glove box/bike tool kit, I went ahead and ordered a UT210E. I paid about 25 Eurobucks on eBay. The unit that came was manufactured in September of 2017. Here are some observations:

• the PCB looks like it's of decent quality, but it was covered with some sort of white residue (like it was washed in dirty water) and there were quite a few loose solder balls stuck to it. Also, the leads of the input protection components were way too long and were poking holes in the back of the LCD. I know, it's a Uni-Turd, so I opened it up, cleaned the PCB with alcohol and trimmed the component leads before I even turned it on.
• the DC current measurement is quite sensitive to outside influences from metal objects and magnetic fields. This is due to the very wide gaps between the cores (plastic between the cores plus additional gaps from a crappy fit), leading to a very leaky magnetic circuit. My proper current clamp adapters have milled recesses at the contact points to mount the hall sensors so the cores can fit together without any gap.
• like most (all?) Uni-Turds, this thing cannot handle DC offsets in AC Volts mode. If you feed it, say, 5VDC that has a 500mV 50Hz sinewave on top of it, where a proper meter would simply read 500mV, the Uni-Turd will constantly beep and alternately flash random numbers and OL. This will bite you in the ass if you don't know about it. Like if you want to measure the AC on a car's alternator to see if any of the diodes are shot, this behavior would be very confusing.
• the display update rate is painfully slow. maybe 2 readings/sec? I wonder if this could be changed via an EEPROM setting?

All in all, you get about what you pay for.

[stj]

none of what you posted matches my experiences of unitrend products.
given how little you paid - you probably got a clone.

[mos6502]

Yeah, nah, it's not a clone. First off, nobody clones Uni-T. The same way how nobody clones dog turds. It came with the original box, pouch, probes, manual, etc. The PCB is identical to other photos and videos on the web. Here's the eBay link where I bought it: https://www.ebay.com/itm/UNI-T-UT210E-Digital-Clamp-Meter-Multimeter-Handheld-RMS-AC-DC-Mini-Resistanc/252445358891?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

none of what you posted matches my experiences of unitrend products.

What, your meter can read AC with a DC offset? It has a faster display update rate?

[Kbird]

Maybe it's cos you are too Close to the Earth's Magnetic Poles in Antarctica ?   

for the Price I think they do fine....

[bitseeker]

Antarctica is a pretty harsh environment for all kinds of equipment.

[Circlotron]

the DC current measurement is quite sensitive to outside influences from metal objects and magnetic fields. This is due to the very wide gaps between the cores (plastic between the cores plus additional gaps from a crappy fit), leading to a very leaky magnetic circuit. My proper current clamp adapters have milled recesses at the contact points to mount the hall sensors so the cores can fit together without any gap.

The next hack for someone here to try should be making the open ends of the jaws fit together more closely and see if that improves the situation. On the 2A DC amps range it is a bit of a pain having the reading wander around all over the place if the clamp orientation is changed.

[Johnex]

Hi!
Thanks so much for the mod values.

I went the solderless route and for any newcomers, here is how i did.

I am using a CH341A with a SOIC8 test clip from aliexpress, and the software for the device. Find where pin 1 on the clip is by buzzing it out, then following the markings on the silk screen to connect the test clip to the programmer like in the photos bellow. It will be the half of the slot farthest from the usb.






Connect the clip to the clamp in the right orientation.



Set the clamp to 2A or any other current mode. Run the program and find Type -> 24EEPROM, Manu -> Atmel, Name -> AT24C02A. Hit Read and the values should change from FF to others. Save these values to a bin file, they are your original memory backup. Now ready to mod, here are the values i used, they are a combination of the posts by flywheelz and stj, thanks guys:

Code: [Select]

UNI-T UT210E Modifications
--------------------------

ADDR : OLD | NEW
================

10000 Count (DM1106 chip ONLY, check it!)
---------
10: 70 10
11: 17 27
12: 98 D8
13: 08 27
14: BE D4
15: 00 03

2A Dotless Calibration (Copy values from 50 to 56, 51 to 57)
---------
56: 00 ??
57: 80 ??

2A Modes (1. Dotless DCA, 2. Dotless ACA, 3. Dot DCA, 4. Dot ACA)
---------
87: 17 1C
97: 16 1D
A7: 00 16
B7: 00 17

20A Modes (1. Dot DCA, 2. Dot ACA)
---------
8B: 19 18
9B: 18 19

100A Modes (1. Dot DCA, 2. Dot ACA)
---------
8D: 1B 1A
9D: 1A 1B

Expand 100A To 1000A (DM1106 chip)
---------
07: E8 10
08: 03 27

Extra Modes (1. Continuity, 2. Ohms, 3. Diode, 4. Capacitance)
---------
8F: 07 09
9F: 09 07
AF: 0A 0A
BF: 0B 0B

V Modes (1. DCV, 2. ACV, 3. DCmV, 4. ACmV)
---------
8E: 04 03
9E: 05 04
AE: 00 05
BE: 00 06

NCV, NCV mV
---------
9C: 00 02
AC: 00 1D

Power Off 1 Hour
---------
FB: 0F 3C

Endless Backlight
---------
FC: 0F 00

Low Battery Warning 15Sec
---------
FD: 80 8F


Copying calibration values is mandatory if you are using the dotless modes.

After altering the values of your choice hit Auto to do a chip erase, write and verify. Done Test it out.

Do not just copy the values in the screenshots bellow. Remember you have calibration values unique to your meter. Follow the text above wrapped in the code block, changing the values one by one carefully. You can look at the changes bellow as a reference to see what hex addresses should have changed.




Link to the CH341A:
https://www.aliexpress.com/item/CH341A-24-25-Series-EEPROM-Flash-BIOS-USB-Programmer-with-Software-Driver/32688496935.html

Link to the CH341A software:
https://tosiek.pl/ch341-eeprom-and-spi-flash-programmer/

Link to the test clip:
https://www.aliexpress.com/item/Free-Shipping-New-1Pcs-SOIC8-SOP8-Flash-Chip-IC-Test-Clips-Socket-Adpter-BIOS-24-25/1902568501.html

[Martini]

the software for the device

Which is...?

[Johnex]

the software for the device

Which is...?

Oh sorry, its called exactly the same as it says in the screenshots, "CH341A Programmer". You can find it here:
https://tosiek.pl/ch341-eeprom-and-spi-flash-programmer/

[mos6502]

So I'm guessing there's no datasheet available for the DM1106EN? How did you guys figure the EEPROM locations out? Trial and error? Personally, after using the meter for a while, the most useful hacks would be a) to increase the display update rate and b) to disable the beep every time you turn the dial ... god, that's annoying.

[Johnex]

From what i understood the only thing that really changed from the new chip and the old one is the counts? From pin and features they are the same, so the old datasheet would still apply:

http://www.kerrywong.com/blog/wp-content/uploads/2016/04/DTM0660DataSheet.pdf

There is no setting for the beeper. If it really bothers you, might as well desolder it?

[mos6502]

Thanks, after reading the datasheet, it's clear that both the update rate and the beeper function are not configurable. Oh well.

Little offtopic, but I just came across this clamp meter:

http://www.youyigao.com/en/cp2_1.asp?bid=136&tid=136&id=233

Only 10mA resolution, but has quite a few more features than the UT210E and can be had on ebay for slightly less. Seems more useful for automotive use.

Another alternative:

https://www.ebay.com/itm/MS2108A-Digital-Clamp-Multimeter-Current-Resistance-Capacitance-Frequency-Test/273045893087?hash=item3f92cdafdf:g:JSkAAOSwD39abuid

This has to be the cheapest DC clamp meter. Looks like it was made by the same manufacturer as the Uyigao. Similar case, similar features, but only 4,000 counts, no TRMS and no temperature. Maybe an older version of the above?

[Martini]

the software for the device

Which is...?

Oh sorry, its called exactly the same as it says in the screenshots, "CH341A Programmer". You can find it here:
https://tosiek.pl/ch341-eeprom-and-spi-flash-programmer/

Thanks.

[edgelog]

I succeeded in reprogramming the eeprom in my UT210E after minor struggles. Just reporting here how I did it, maybe it helps someone. Most (all?) of this has been mentioned here and there in this thread before.

Got the TL866A programmer with a lot of adapters from an Amazon seller, downloaded the software from xgecu.com. I hooked it up to the eeprom using the great little probes that came with my Saleae 8 bit logic analyzer. These probes are small enough to easily hook the legs of that eeprom without crowding out each other. They also have two pin connectors each, making it easy to hook up both the programmer and a scope probe to the same gripper.

Initially, I couldn't get the TL866A to program the eeprom, though it could read it out just fine. As you can see in the scope image, where CH1 is SDA, CH2 is SCL, and CH3 is WP, WP goes high during programming, which isn't right. (I'm also not clear on why SCL is missing during a large section of the programming.) I don't know if the programming isn't driving WP right, or if the UT210E pulls up too hard, but simply connecting WP directly to ground fixed that, and programming could proceed without a hitch. I should add: don't forget to set the main rotary switch on the UT210E to anything except "off". In short, I didn't need to modify the UT210E in any way, unsoldering anything, or adding in connector pins.

The original contents of the eeprom in my UT210E isn't exactly the same as others I've seen in this thread, so I'm including it here. I'm also including the changed contents after programming. My UT210E has the later main chip, the 1106.

[stj]

the reason your contents are slightly different is because it contains calibration data - so keep a backup! 

[Martini]

I received my 213C, currently trying to build-up the courage to open it up and see what's in it...

[lavardera]

I noticed that ExTech is selling what looks like a rebadged version of the UNI-T UT210E - look at their model MA63. I'm not sure if the specs are the same as the UNI-T. At least on one of the illustrations on the Amazon listing they are describing the MA63 as 6000 count, which makes me wonder about all code modifications discovered here.

ExTech als has a MA61 in the same form factor with out the Clamp DC Amps which appears similar to the UNI-T 210D?

Edit: I checked the ExTech web site and the spec on the MA63 is 6000 count. Love to see you all look at the code from that unit. Maybe you could find a way to make the 6000 count hold on the 210E? Link to MA63: http://www.extech.com/display/?id=17215

[lavardera]

This is not a case of the ExTech and the UNI-T sort of looking similar - the molding of the body, the display, the clamp - its all IDENTICAL.



The specs seem slightly different - note the Hz function on the Volts place on the dial for the ExTech. And the Amps ranges are different. What is the chance that the main board and processor is the same, and all the capabilities are being varied by software?

[perieanuo]

This is not a case of the ExTech and the UNI-T sort of looking similar - the molding of the body, the display, the clamp - its all IDENTICAL.



The specs seem slightly different - note the Hz function on the Volts place on the dial for the ExTech. And the Amps ranges are different. What is the chance that the main board and processor is the same, and all the capabilities are being varied by software?

99%

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

[Martini]

Gosh, the Extech is ugly

One thing I noticed only after having received the meter (and it bothers me): there is no manual range selection

[lavardera]

99%

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

99% what? 99% alike? Do you have the ExTech, have you opened it up?

[perieanuo]

You got your answer. You asked what is the probability bla bla bla, I said 99.what's unclear? Rebranding sounds familiar to you? Same shape, same LCD, same switch. No need to be aggressive if you don't know, put questions on the table without even putting together q and a.

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

[lavardera]

Sorry - you are misreading. No aggression intended. Just hoping there was more substance to your reply, but you don’t own one.

Interesting - I read elsewhere that ExTech had a recall on these models due to loose screws on a terminal contact. Found this on their site.  http://www.extech.com/display/?id=16536

[macboy]

You got your answer. You asked what is the probability bla bla bla, I said 99.what's unclear? Rebranding sounds familiar to you? Same shape, same LCD, same switch. No need to be aggressive if you don't know, put questions on the table without even putting together q and a.

Envoyé de mon HUAWEI NXT-L29 en utilisant Tapatalk

It is not the same. Look more carefully. The Extech has a 600 mA range for AC only (0.1 mA resolution) plus AC/DC 6 A and 60 A ranges.  The Uni-T has AC/DC 2 A (6 A with mods), 20 A (60 A with mods) and 100 A ranges.

[lavardera]

Correct - the Amp ranges are different between the MA63 and the UT210E. But the Amp ranges are also different between the UT210E and the UT210D. I believe somebody posting here has opened the two Uni-T models and said the boards were slightly different. So I'm curious how different the ExTechs are inside.

Here is something - if you look closely at the image at the bottom of the link above there is a picture of the back of the ExTech MA63. There is a sticker there that has an ETL seal and a Certification number. That would mean the meter was independently tested and the rating certified. The UT210E definitely does not have that. The one I bought does not, and I've not seen a certification affixed to any of the units posted here. Somebody would have spoken to that if it existed.

So I think that could spell out significant differences inside the units? I mean what would be needed to actually achieve the ratings posted? Some bus fuses? Or might the board designs be very similar? I can't justify spending the $200 to find out, but I'm curious.