A look at the Uni-T UT210E

[hgg]

I have been unable to recreate the results you are showing

Sorry, I forgot to mention that the 60Hz AC waveform is above the 0V line and the lowest troughs touch
the 0V line.    Its a positive AC waveform. 

Only the Brymens fail this test.   Can you try again ?

[indman]

hgg ,to perform the same measurement, only via the separating condenser.

P.S. hgg in this case to you it is possible to use such mode of measurement, as on a photo

[Fleetz]

Just ordered a UT210E....appreciate all that contributed their feedback.

[milamber]

Great job!
Also ordered a Voltcraft VC-330 (31€, exactly the same PCB even labeled as UT210E )
Programmed the EEPROM (24C02A @SOIC8) with TLC866A and the recommended SOIC8 adapter http://www.ebay.com/itm/252135254293.
Just writing this comment to repeat the importat hint from flywheelz: Switch UT210E to ~V mode otherwise it won't work.

Has anyone yet found a way to disable the the beeping sound when switching between the measurement modes? Kerry D. Wong did not: http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/
As far as I read the thread, RS232 and Min/Max do not seem to be supported by the UT210E Firmware.

[hgg]

hgg in this case to you it is possible to use such mode of measurement, as on a photo

Just tried the AC+DC function on the Brymen and although the AC+DC value is correct, the AC component
is still showing wrong values after around 450mV.

If you do not know beforehand that your signal is a positive AC waveform you might get completely
wrong readings.  Brymen should sell them with a decoupling capacitor free of charge...   
To be fair, the AC+DC reading is spot on with the oscilloscope.

[Ivan7enych]

Made an output for oscilloscope.
To remove offset I use 1.1V from C15 as a ground.

To make output better, it's worth to add opamp with 20KHz lowpass filter to remove high frequency noise generated by microcontroller.

[evava]

Why you did not use shielded cable instead?
Or at least twisted cables?

[IanB]

Does anyone know how to adjust this meter to improve the accuracy of the DC current readings? My sample of the meter is consistently reading about 2% low on the 2 A range and it would be nice to tune it up a bit.

There are three trim pots inside and joeqsmith mentioned adjusting them in a previous post. But I'm not clear exactly what they do or how to adjust them to best effect. Has anyone got any info on what each of them is for?

[IanB]

There are three presets marked VR4, VR+ and VR-. Does anyone have an idea what they do?

You guys have been hacking the firmware, so surely three little presets are not such a mystery? 

[Macbeth]

There are three presets marked VR4, VR+ and VR-. Does anyone have an idea what they do?

You guys have been hacking the firmware, so surely three little presets are not such a mystery? 

I disagree. These guys are hacking the "settings" of this meter, or the artificial limits. The ones pre-programmed to allow the seller to charge much more for a different model using pretty much the same hardware. I think this is a common theme lately.

The firmware is out of bounds, though interesting hacks are possible beyond what the firmware programmers envisioned as can be seen.

As for the VR's, this is analog stuff - surely you can work this out yourself with a rudimentary "reverse engineering" using a multimeter. Make sure you measure all your VR's and take a photo before twiddling and then mess about to your hearts content - tabulate some data and work out from that how they affect V/R/I.

You will always be able to turn it back to "factory" if you cock up. You could also find something interesting

[dav]

Just curious to know if UT210E shares same hardware of UT211B.

[mikga32]

The one I got a week or so ago was DOA
All it did was beep and when pressing the Zero key showed a Err.8
Sent back...

[retiredcaps]

Sent back...

Was shipping back more than the cost of the meter if you sent requesting Canada Post tracking/signature?

[tszaboo]

I just got my UT210E. This meter is neat. Now I have to see if it discharges rechargeables to 0V and kills them or not.
I have a question though. DC 2A range has some 0.3A offset. I understand an offset in the DC A is possible, but this looks little on the high side for me. How much offset do you guys have?

[hgg]

30ma - 100ma depending on location.

[evava]

400-450mA.

I think that joeqsmith somewhere wrote how it can be compensated, but only after demagnetizing of the clamp.

Just zero it.

[hgg]

When I was writing the firmware and trying out some changes I left a small wire still connected.
The offset then was around 10mV... 

When I removed the small wire, it returned back to its 40-100mV offset.

[Fennec]

80-100mA max.

I left a small wire still connected.

?? connect to what ?

[hgg]

If I remember correctly, to the capacitor connected to the reset pin.

[smile]

What good does 6200 count hack do if the UT210E is ±?2%+3) DC Current (A).

According to this:
https://www.electronics-related.com/showthread/sci.electronics.basics/62666-1.php

There are 2000, 3200, 4000, 6000 etc count meters on the market that all
use 4 digits.

The really important difference is in the accuracy built into each model
 -   there is really no point in having more than 2000 counts shown if the
basic accuracy is only 1%.

Generally, 2000 count meters have 0.5 % DC accuracy, 3200 count meters
0.3%, 4000 count 0.25% and 6000 count 0.15%.

[smile]

Now if somebody would add MIN MAX features that would be enough for me to try and hack it.

[Fennec]

What good does 6200 count hack do if the UT210E is ±?2%+3) DC Current (A).

Thats crap. Accuracy and counts are total different things.

[smile]

The video explains it that seeing more digits does not mean more accurate measurement !
Same thing as I said.

The hack does increase accuracy from ±?2%+3) DC Current (A).

Hand held it's hard to measure within 15-20mA DC Current (2A scale anyway)

[Fennec]

The hack does increase accuracy from ±?2%+3) DC Current (A).

NO ! Watch the Video again.

[macboy]

What good does 6200 count hack do if the UT210E is ±?2%+3) DC Current (A).

According to this:
https://www.electronics-related.com/showthread/sci.electronics.basics/62666-1.php

There are 2000, 3200, 4000, 6000 etc count meters on the market that all
use 4 digits.

The really important difference is in the accuracy built into each model
 -   there is really no point in having more than 2000 counts shown if the
basic accuracy is only 1%.

Generally, 2000 count meters have 0.5 % DC accuracy, 3200 count meters
0.3%, 4000 count 0.25% and 6000 count 0.15%.

Accuracy is very different from Resolution.

If extra digits of resolution beyond the accuracy of the instrument were actually worthless, then all those people who buy $10000 8.5 digit multimeters like the 3458A must be fools. After all, 5.5 digits is enough for a 0.0008% (1 year spec) instrument, right? So why are those extra three digits so valuable? One reason is that they can let you see a small change in the value that is even smaller than the absolute total error of the measurement.

This thread is about this meter, and largely, how to hack this meter to add features, adjust calibration and so on. If you would rather discuss Accuracy vs Resolution, don't derail this thread. Instead, go discuss it in the metrology forum. You will find no lack of bright folks there to inform you.