Uni-T launches the UT117C multimeter

[makz]

can someone upload a dump of EEPROM P24C02A?

Here is mine.

I tried to upload yours firmware, my device greatly underestimates the voltage (- 0.1%). I noticed that I have a soldered eprom, so the firmware may be from another unit

[makz]

can someone upload a dump of EEPROM P24C02A?

Ok! 

I've uploaded yours firmware, it's a little more accurate than mine. If someone else posts the firmware, I can choose the optimal one))

[geb]

I tried to upload yours firmware, my device greatly underestimates the voltage (- 0.1%). I noticed that I have a soldered eprom, so the firmware may be from another unit

Are you saying your EEPROM appears hand-soldered? Anything's possible, but the rework could be for a more innocent reason.

[makz]

I tried to upload yours firmware, my device greatly underestimates the voltage (- 0.1%). I noticed that I have a soldered eprom, so the firmware may be from another unit

Are you saying your EEPROM appears hand-soldered? Anything's possible, but the rework could be for a more innocent reason.

My unit was used and sold as new. So, its was deception. There are components on the board that are not yet factory, I’ll try to restore its accuracy. I hope eeprom from my device

I think I've found a calibration constant for DCV. Now DC voltage correct. I'll check other functions later

[geb]

Hmm, how do you know it was used? Reworking a board is normal, especially in early production. Was there other evidence besides the EEPROM?

I think I've found a calibration constant for DCV.

Excellent! Does the change affect all DCV ranges, or just one? And if it affects all DCV ranges, do you notice any change in resistance ranges?

[makz]

Hmm, how do you know it was used? Reworking a board is normal, especially in early production. Was there other evidence besides the EEPROM?

I think I've found a calibration constant for DCV.

Excellent! Does the change affect all DCV ranges, or just one? And if it affects all DCV ranges, do you notice any change in resistance ranges?

DCV all ranges more accurate now. I will compare with pm2525. Resistance range without any changes, im not sure

[makz]

old eeprom and new eeprom

[geb]

It's been a busy time, but I revisited UT117C briefly.

EEPROM offsets 01 and 02 are an overall DCV calibration value. 01 is the MSB, 02 is the LSB.

I discovered that my unit's DCV range isn't zeroed perfectly. So, as I calibrated DCV by manually updating the value in offset 02 of EEPROM, I checked both +5V and -5V. I updated offset 02 to a level where +5V is shown as three counts too high, and -5V is two counts too low.

Linearity is okay but not perfect when I check 1VDC, 2V, ... up to 6V. The 5V is a bit off and the 6V is off by quite a bit more.

[ru_tash]

Hi, nobody mention capacitors measurements, sad surprise for me - the resolution 1nF, so to measure 10000pF will display 9nF ((.
Other than that all ok.

[BILLPOD]

Mine reads 0.01uF......go figure.

[ru_tash]

I don't have reference voltage but I have set of resistors with 0.01%, is it reasonable to make conclusion regarding accuracy of VDC upon result of resistors measurements accuracy?

ps. update, it seems like my assumption correct, the resistors measurement of my specimen within 0.03%, and voltage taken from AD588AQ was 10.000V

[geb]

I don't have reference voltage but I have set of resistors with 0.01%, is it reasonable to make conclusion regarding accuracy of VDC upon result of resistors measurements accuracy?

The VDC and resistance calibration values seem to be stored separately.

My UT117C's VDC ranges are "bang-on" accurate at their low end such as 1.0V, 2.0V, but are off by 5-6 counts at 5.0V and are off by many more counts at 5.9V. In comparison, the 60K resistance range with my 0.01% resistors is off by the same amount throughout. My readings are typically five counts below the resistor's rated value at 10K, 20K, 30K, 40K, 50K.

[ru_tash]

I don't have reference voltage but I have set of resistors with 0.01%, is it reasonable to make conclusion regarding accuracy of VDC upon result of resistors measurements accuracy?

The VDC and resistance calibration values seem to be stored separately.

My UT117C's VDC ranges are "bang-on" accurate at their low end such as 1.0V, 2.0V, but are off by 5-6 counts at 5.0V and are off by many more counts at 5.9V. In comparison, the 60K resistance range with my 0.01% resistors is off by the same amount throughout. My readings are typically five counts below the resistor's rated value at 10K, 20K, 30K, 40K, 50K.

 it looks like nonlinear ADC

[scale]

What do you think about UT117c and UT185A which multimeter will be more accurate for measuring currents less than 2mA?

[ru_tash]

What do you think about UT117c and UT185A which multimeter will be more accurate for measuring currents less than 2mA?

UT117c resolution for current 0.1mA
UT185A - what is this?

[smokehead]

Does anyone test 117c vs 161e(61e+)? Any significant differences?which one better for the bench DMM?

[rej]

Comparison between UT117C, UT61E+ and a Fluke Calibrator
https://www.bilibili.com/video/BV1b8411f7pP/?spm_id_from=333.788.recommend_more_video.1

[Purvirs]

Hello everyone !

This DMM ut-117c has a BlueTooth driver. I like the USB interface of the ut-61e (and ut-71).

Does this ut-117c have a usb interface?

Thanks you !

1.  Do any of UNIT-T blurbs about this meter make any mention of USB?

2.  Do any of the photos a few posts above show any signs of a USB connector?

Answer those questions and you have the answer to your question.

in terms of USB connection to a computer, actually I've verified that using an USB-BLE dongle, the UT117C can be connected to a computer.
of course, need to install an app on computer called "TsDMMViewer", this app can discover and make connection to a lot of DMMs (bench type and handheld).
currently connecting to DMMs by BLE to the app on a PC, the only compatible dongle is called "BLED112-V1", with this dongle, data can be pulled and logged on the PC, charts and curved based on the pulling data are also available.
I've tried connecting to UT117C and F289 (need an IR3000FC adapter), both of them are working fine.

hope this can be helpful.

[ru_tash]

So, how to calibrate ut117c?

here is post from Chinese source https://www.mydigit.cn/forum.php?mod=viewthread&tid=393114&page=1#pid14696150

what is that SW1 jumper?
 

[valcher]

what is that SW1 jumper?
 

This is probably the MIN/MAX button.