A look at the Uni-T UT210E

[kkontak]

Just found out this hack and tried on my UT210E. Worked great!

Two observations:

1. By adding a 2nd feature (AC mV) in NCV mode, using the below 2-byte hack, you also add a 3rd feature (AC A 6000A) which seems silly to me. The $1D byte is really useful for the mV feature to work? Because all it does, is to enable the 3rd feature.

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

2. When I opened my unit, I noticed a QC fail. The R37 resistor was soldered only in one of the pads. Still worked tho, even after years of beatings around in the toolbag on many work fieldtrips.

[ceut]

Time has passed since my contribution here...2017   
A quick follow up of a problem of one of my 2 UT210E (the one I have given to my brother).
I have to fix his FAAC D600 motherboard (from a motor garage door) which has failed and some burned part on it.

So, after having fixed it at home, I have gone to his home, and when I have rechecked the power voltage line, his UT210E reads 51V DC    (for a 24AC 86VA transfomer, which I have checked at home at 24.85V RMS on my Keysight U1233A and with my Siglent DSO 68V peak-peak (34V max and -34V min)).

=>So big fail for this 6 years UT210e old that I have flashed and contributed for mod it here  https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/msg1316832/#msg1316832

I have worked on it for about 3 hours, reflashing other 24C02 calibration file, checking many parts etc..
All other functions worked well.
Then I have removed fully the motherboard, and found the issue 
==> Wear of the rotary switch !   
2 traces have lost their solder mask  as you will see on the photos.
I have put a piece af tape, and it is working again, with the good calibration I have made 6 years ago 
Now I have to find how I can isolate this traces... will try some UV solder mask

[kloetpatra]

I mainly use mine in 2A mode (once a week). A while ago I noticed incorrect Amp readings or mode changes (beep) without touching. Firmly pressing the selector wheel the issue goes away. So I think it's a bad contact in my case.

Just checked the inside and I can see there's way much more grease. Maybe you should add some grease too?
While the traces still show no signs of wear there's a little bit of green residue on one of the copper spring contacts.

[ceut]

I mainly use mine in 2A mode (once a week). A while ago I noticed incorrect Amp readings or mode changes (beep) without touching. Firmly pressing the selector wheel the issue goes away. So I think it's a bad contact in my case.

Just checked the inside and I can see there's way much more grease. Maybe you should add some grease too?
While the traces still show no signs of wear there's a little bit of green residue on one of the copper spring contacts.

wow 
This grease was put originally from factory ? Is it a recent batch ?

On my 2 UT210e from 2017: no grease at all inside.

I have fixed the 2 mine which were having the exactly same wear problem on the same place/traces.
=>Fixed with UV solder mask, then a very little WD40 on the rotary switch+trace - hope it will last with that.

[kloetpatra]

This grease was put originally from factory ? Is it a recent batch ?

Yes, I didn't add anything. I think it's from 2015. Nice fix, I hope it'll last long. I'd rather recommend silicone based grease. WD40 technically is not a lubricant. Moreover it is hydrocarbon based. Amorphous plastics and hydrocarbons don’t play well together. Hydrocarbons attack the chemical structure of amorphous plastics and break them down. It would be safe for crystalline plastics.

amorphous: PC, Styrene (including ABS), PVC
crystalline: PP, PET, PE (all types), Nylon

[cybermaus]

Apologies if this was mentioned before in this very long post.

I have a UT210E, and it has a DM1106EN chip
But I have had it for a very long time. Maybe since 2015 or so, so it may be one of the first ones. PCB reads "UT210E Rev.1"

I hate the backlight going off too soon, and always having to move it to DC, so finding this tweak seems useful. And I had all the stuff like CH304 and clamp already in a drawer, so I thought I give it a try.
Using this video and this specific post as a guideline.

And it all went very well. EXCEPT.... The content of my EEPROM is SOOO much different then the examples shown. None of the BEFORE values in the aforementioned post match.
So I do not dare to make the changes

Any suggestions?


Edit: anyone know how to link a YT video without it immediatly expanding and taking up all space?)

Edit2: Figured it out. Bad USB cable (too long for the CH304, erratic results)
When I plugged the CH304 directly into the laptop, it went correct the first time, all values as expected, all mods worked. (well, I did no test 1000 Amps yet)

[KungFuJosh]

Edit: anyone know how to link a YT video without it immediatly expanding and taking up all space?)

Usually the shortened "Share" URLs don't get embedded as the full video.

[cybermaus]

Usually the shortened "Share" URLs don't get embedded as the full video.

Indeed, thanks.

[jewelie]

Am I right in thinking this CPC/Farnell TENMA 72-2985 appears to be a UL tested, certified version of the UNI-T UT210E?

https://cpc.farnell.com/tenma/72-2985/clamp-meter-mini-200a-ac-dc/dp/IN07620?st=dc%20clamp%20meters

[cybermaus]

Am I right in thinking this CPC/Farnell TENMA 72-2985 appears to be a UL tested, certified version of the UNI-T UT210E?

https://cpc.farnell.com/tenma/72-2985/clamp-meter-mini-200a-ac-dc/dp/IN07620?st=dc%20clamp%20meters

Sure looks like it. Mind you, legal mumbo jumbo not being my forté: Does "conforms to UL" mean the same as "UL certified"
I once had a discussion about IEC-61131, where a device I helped designing "conformed to IEC-61131", but it was never send for certification.

[Oszitrek]

<sup>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</sup>


Hi everyone ,

I modified follow page 20, and detect a problems with value of  switch Range up : example 10000 counts , they set address 12,13  =27D8H =10200 mean when DMM counter over 10200 will be switch range , but if voltage measure is 10v so it will show OL on screen , really not good  . Solution is set switch range up= 9800 and switch range down =960 so we will cover full range , voltage display auto switch range when over 9800 count , ex: 9.700v ->9.799v -> 09.80v -> 10.00v ->50.00v , down 10.00 ->09.80 ->09.70v ->9.600v ->9.500v . should be better

Hello,
You right! This is the good upper and lower range.
UPPER RANGE: 26 48 = 9800
LOWER RANGE: 03 C0 = 960

[Paul T]

Time has passed since my contribution here...2017   
A quick follow up of a problem of one of my 2 UT210E (the one I have given to my brother).
I have to fix his FAAC D600 motherboard (from a motor garage door) which has failed and some burned part on it.

So, after having fixed it at home, I have gone to his home, and when I have rechecked the power voltage line, his UT210E reads 51V DC    (for a 24AC 86VA transfomer, which I have checked at home at 24.85V RMS on my Keysight U1233A and with my Siglent DSO 68V peak-peak (34V max and -34V min)).

=>So big fail for this 6 years UT210e old that I have flashed and contributed for mod it here  https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/msg1316832/#msg1316832

I have worked on it for about 3 hours, reflashing other 24C02 calibration file, checking many parts etc..
All other functions worked well.
Then I have removed fully the motherboard, and found the issue 
==> Wear of the rotary switch !   
2 traces have lost their solder mask  as you will see on the photos.
I have put a piece af tape, and it is working again, with the good calibration I have made 6 years ago 
Now I have to find how I can isolate this traces... will try some UV solder mask

I would (and did) use a very small amount of dielectric grease and be done with it.  By adding tape, a non-conductive material is introduced, which can wear much faster than the copper trace would, potentially polluting the contact area.  Also, the edges of the tape have exposed adhesive with can also liberate and cause connection issues.  And tape deteriorates more quickly than the copper and soldermask. 

Based on what I saw with mine, the multimeter range selector without modification could last through tens of thousands of cycles without risk of broken traces, but the same cannot be said of the tape or whatever material that is used.  The lower strength soldermask was broken, not the copper.  And now the soldermask over the trace is gone.  Problem already solved.

If they used gold-plated spring contacts, I might feel differently.  You don't want high quality gold surfaces polluted with copper residue.

BTW, my PCB needed really aggressive cleaning due to get rid of a problem where a megohm resistance was detected without leads connected.  It developed this issue after only one year, never exposed to "the elements". 

The selector wheel also had stubborn operation and needed pulled apart, surfaces smoothed, and reassembled with grease.  Now I can easily change the range with one finger again.

[joeqsmith]

Time has passed since my contribution here...2017   
...
Then I have removed fully the motherboard, and found the issue 
==> Wear of the rotary switch !   
...

I stopped contributing once Behemot joined and the mods got involved.   
https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/msg1048561/#msg1048561
Behemot posted a comment on my YT channel not too long ago.  Guessing they thought I would not remember them.   

Later, I did post about some mods I made to increase the BW.   This was a major hack making the probe work my like my vintage Tektronix RF current probe using a separate DC and AC path.   
https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/msg1101265/#msg1101265

Seven years later,  noticed your post about the switch failures.   We purchased six or so of these and I have two at home.  I started to see switch failures in the first 2 years.  Most are being used for a current probe only.   So far, I have been able to recover them by cleaning the contacts and have been applying dielectric grease to the ones that have had a problem. 

The only one I am aware of that was damaged so far was used to measure the output of a mag on a lawn mower.   I really wish UNI-T had done a better job with this product.  It's been very useful.

***
Catch you in another six.

[cybermaus]

My brother accidentally bought a UT211B after I advised him the UT210E
They sure do look alike.

Since he too plans to mostly use it DC (for his camper) I also managed to mod AC default to DC default, but the UT211B is slightly different.
Mostly the switch position colums are swapped. Here is the original EEPROM, and the mods I made, as well as what I figured out.

Differences (not exhaustive) EDIT/ERROR: value 1F for Hz seems correct for 210B, but not for 210E


Original EEPROM


Modded EEPROM


Also, my programmer image indicates the incorrect chip position, even though it is the same 24C02A
Also do not forget to set the rotary switch in a Amp or NCV position to read/program

[darkcastle]

I like this model and form-factor, however, I would like to have the ability to get the max/min value of DC current. I tried looking to see if there's another Uni-T like this one with max/min added and couldn't find one. I thought I'd check here in case I missed it or if there's one very similar to this model that can measure DC current with similar measuring range and max/min.

[Aldo22]

I like this model and form-factor, however, I would like to have the ability to get the max/min value of DC current. I tried looking to see if there's another Uni-T like this one with max/min added and couldn't find one. I thought I'd check here in case I missed it or if there's one very similar to this model that can measure DC current with similar measuring range and max/min.

With the Owon CM2100B you can log everything and view it on your smartphone, for example.
Maybe that would be something for you?

[cybermaus]

With the Owon CM2100B you can log everything and view it on your smartphone, for example.
Maybe that would be something for you?

I think @darkcastle was thinking more of a peak-hold function.
Or at least, that is what I in the past was missing, maybe that is why I understood his suggestion as I did.

The difference is a simple peak hold holds the highest of the samples at the 6 samples per second sample rate of a typical DMM
Logging would only get you the value if it holds for a second or more.

And yes, it would be nice if we discovered another Uni-t with peak-hold and figured out the internal function byte for it, and then discovered that function was still working on this model. But I am not holding my breath.

[Aldo22]

The difference is a simple peak hold holds the highest of the samples at the 6 samples per second sample rate of a typical DMM
Logging would only get you the value if it holds for a second or more.

I don't think there's a big difference.
Uni-T writes: "2~3 times/s sampling rate"
Owon CM2100: "Numerical Value Conversion Rate: 3 times/second".
You can also see from the screenshot above that it logs at least 2 readings per second.
Both are not oscilloscopes. 

[darkcastle]

With the Owon CM2100B you can log everything and view it on your smartphone, for example.
Maybe that would be something for you?

I think @darkcastle was thinking more of a peak-hold function.
Or at least, that is what I in the past was missing, maybe that is why I understood his suggestion as I did.

The difference is a simple peak hold holds the highest of the samples at the 6 samples per second sample rate of a typical DMM
Logging would only get you the value if it holds for a second or more.

And yes, it would be nice if we discovered another Uni-t with peak-hold and figured out the internal function byte for it, and then discovered that function was still working on this model. But I am not holding my breath.

Yes, that’s correct, but the Owon CM2100B is an interesting suggestion. So I am about to order the UT203+, is that a good option?

[Aldo22]

Yes, that’s correct, but the Owon CM2100B is an interesting suggestion. So I am about to order the UT203+, is that a good option?

I don't know the UT203+, but just a tip:
Don't underestimate the possibilities that a Bluetooth connection on the clamp meter gives you!

You can't always mount the clamp in such a way that it is easy to read.

For example, you can attach the CM2100B somewhere deep in the engine compartment of your car and then sit in the car and conveniently read the measured values on your smartphone.
You can also have them recorded and read them out later on your smartphone.

That's pretty cool.

[cybermaus]

Don't underestimate the possibilities that a Bluetooth connection on the clamp meter gives you!

The logging is tempting. I have been in situations where I could have used that. Equal for the readout from weird constricted angles.
But I already have too many DDM's.

Small worries would be battery life, and app life (given Dave's recent video about an Agilent bluetooth DMM where the app is no longer available in the store)
And can I hack the eeprom to do DC first and extent backlight/sleeptime?

[kmoonwalker]

Small worries would be battery life, and app life (given Dave's recent video about an Agilent bluetooth DMM where the app is no longer available in the store)

usually 3-4 versions of android backwards are supported and sadly they always tend to design actual control app edition to older version of Android so often this problem including toys for kids to control via mobile, etc :/

then on most modern phones you cannot instal from apk on SD like in old days without rooting it to disable app versions protection

[Aldo22]

Small worries would be battery life, and app life (given Dave's recent video about an Agilent bluetooth DMM where the app is no longer available in the store)

If you log longer (hours, days), you can turn off BT. This saves batteries.
Then turn BT back on and read the buffer with your smartphone.

I use the app with an old android 6.0 phone without any problems.
It also works with other OWON BT devices, which increases the likelihood that it won't just disappear.
https://play.google.com/store/apps/details?id=com.owon.imeter
https://apps.apple.com/de/app/owon-imeter/id1607020484

The data can also be read with ESP32 or Linux.
I have tried it with ESP32 (easiest way imo). It works.
https://github.com/sercona/Owon-Multimeters

Oops, we're off-topic: https://www.eevblog.com/forum/testgear/owon-cm2100b-is-uni-t-ut210e-inspired/

[geralds]

I hope I am not drifting off here... Has anyone tried the Ziboo UT210E?

Apparently DC mA range starts at 1mA, though accuracy is stated at 3%+30. Does this mean that if say 5mA is displayed, this could also mean 35mA?

Maybe I just get the UT210E and look at the mods.

Link to Ziboo: https://ziboo.online/collections/clamp-meter

Copy of manual attached (I received this from Ziboo)

[cybermaus]

I hope I am not drifting off here... Has anyone tried the Ziboo UT210E?

It is another drift yes. Interesting they choose model label UT210E. Like they are not even trying to hide who they are copying.
Or maybe they hope people accidentally select the wrong one when buying a fathers day gift.

Slightly back on topic (as this is true for the Uni-T as well): Afaik *ALL* DC current clamps in the mA range have a offset problem. Meaning even if they display/claim 1mA, with or without 3% error, you should assume that local static magnetic fields will cause it to have a offset of 10's to 100's of mA

Meaning you need to keep the clamp as close to the measured line as possible, in the angle you are going to measure it, so it has the local magnetic flux, then press the zero button, and then do your measurement. So touch the wire without opening the clamp, press zero, then open the clamp and measure.

Mine had a few 10's when I bought it, but over time it increased to 100's, probably due to self-magnitizing.
I did try to demagnetize the head (https://www.aliexpress.com/item/1005004157270142.html) but it only got marginally better.