Connect and fasten the SOP8-DIP8 board to the CH341A programmer. The SOP8-DIP8 board pin 1 should be farthest from the USB connector and adjacent to the fastener so as to align with the 24CXX DIP8 outline on the programmer. Further it is possible to switch the selector on 20A, to press the ZERO button and to nullify indications. At the same time the instrument in hand not to hold, give time for that that indications calmed down, to place the instrument where least of all el./magn. noises and the more so far away from magnets. Overall it's a small device that fits well into the hand. The display is mounted in such a way that it can be awkward to read, either because it's at an angle when pointing the clamp away from you, or because you're covering it with your hand when holding it with your right hand and your thumb on the clamp opening mechanism. Larger clamp meters have the display at the very bottom for this reason I guess. I recorded video of process of resetting to zero of the current indications in the DC mode at UT210E. This method allows to reduce residual indications in the mode of measurement of a direct current (DC 2A Dotless, 2A,20A,100A) without the need for EEPROM correction without the programmator. Thanks of kDnZP from a Russian-speaking forum!

Select/VFC (Blue): Will select secondary functions, holding down the button will enable a low pass filter for AC measurement (VFC). The circuit board has some input protection with two PTC's and 3 MOV's. The input resistors (R37A, R37B, R37C, R37D: 4x2.5Mohm) is split into 4 resistors, between these resistors and the input is a PTC. Screen update rate is unusually fast for Uni-T at around 4 updates per second. Unfortunately, other things are slow: the latched continuity tester is usable, but certainly not fast. Resistance autoranging is slow. Reading current with the clamp is also a tad slow, it usually a second or two for the value to come up to the right area, and then 2-3 seconds more for the last digit to stabilize, so current isn't instant. A big thank you to Dave and his videos on DMM's wow can you imagine being his apprentice, my head would explode after a days work so much info from one guy and i'm not even to sure his videos are cut and edited.Changing the PROM will not impact the drift.I suspect you could run 100 of them an they would all drift roughly the same.I suspect you two main problem will be temperature and placement.When Maxlor posted 10mA in a minute, I can believe it.When I ran that test I was careful to try and hold the temperature as tight as possible and not move the clamp. Measure current with the clamp, use the blue button to select between AC and DC. Zero must be used on DC range The big IC (DM1106EN) is the main multimeter chip and the frontend for the clamp is mounted close to it (U4:OPA4330 Quad OpAmp). REALLY happy after all of the Chinese crap I requested and reviewed. Finally--got a nice clamp meter for DC current and work! Stoked. I've looked at many different clamp meters, and typically they come with one or more of these limitations:

A full set of teardown pictures are here. https://photos.google.com/share/AF1QipPykJgrz2vMySXTkFdst6YsfoTs0Mzs1vmWZXa-XQ5EGBxVeRmFiqj-jO2c44IFcA?key=T01ITXVCa015U0x5WV9UZUV6dUdiSGdXUTBENF93 Cable position within the clamp does not matter btw. As long as the cable goes through the clamp, you get the same measurement. When using the NCV function the display will show a number of -, depending on the electric field. This can usual be used to see if a mains outlet or cable is powered or trace a cable that is just under the wall. This function is always a guideline and not a 100% confirmation of voltage or no voltage. There are two larger chips. The one on the left is a TI OPA4330 quad opamp (Markings: TI O4330A 44K G4 AN50), the one on the right is the Hycom DMM Chip (Markings: Hycom H203 DTM0660L R3MR81A)

UNI-T UT210E Current Clamp/Multimeter

To produce the modified EEPROM image, an original EEPROM image is necessary because there is device-specific calibration data contained in the image. An example original EEPROM image is included at bin/orig.bin, as well as its default modified image as produced by make at bin/mod.bin. There are no major transmission lines visible from my location, and local power is distributed via underground wires. I took the meter outside and tested in two different locations separated by 100 feet or so. Before being zeroed, the meter reads in the 320-430mA range. After zeroing the meter, I tested variability based on orientation. Slightly rotated and tilted up and it read 130mA . Tilted it down, -75mA. The variation was similar when tested in the other location. (Biggest change tends to happen when tilting up vs down.) So today, outside, the variation is around 210mA. I saw earlier in the thread that the meter could become magnetized and require degaussing. I understand this could cause an offset in the reading, but it's not clear to me if it could also cause the variation based on orientation that I'm seeing. Also, I'm not sure which of my power tools or appliances would leak enough EMF to use as a degausser.

When I get a spare moment, I’m going to solder a couple of wires on to the thing and see if my hunch is correct. If so, this will be the cheapest 6000 count meter with RS232 (some soldering required) on the market. :¬) This will read the original EEPROM image, bin/orig.bin, and produce the modified image, bin/mod.bin. To read and write to the EEPROM, ch341eeprom[3] must be present. Dependencies HardwareThey only work with high currents. The lowest range on many devices is 20A or 40A, which gives you 10mA resolution.

It included the DMM, a pair of probes, a pouch and a manual (Both a English and a Chinese version).Zero: Save the current measurement and show the following measurements relative to that value (Very important for DC clamps). Narrowed it down to two, UNI-T UT210D and the UNI-T UT204, just want to see if other guys have brought. One this side is another string of resistors (R27A, R27B, R27C: 3x300kohm), but strange enough they are connected directly to the input terminal without any protection. The NCV voltage led (LED3) and the transistor to drive it (Q2) is also placed here. The clamp claims Cat II 600V and Cat III 300V, and opens to about 16mm, which is plenty. The movement has no play and feels solid. Between 15N and 20N of pressure is required to open the clamp. So my question is is this typical behavior for the meter, or should I exchange it for another? What do others see?