UNI-T UT161E voltage range calibration. - Page 1
Forum section: electronics / repair

author: MisterWilli
author_rank: Newbie
timestamp: January 11, 2024, 01:58:23 pm
content: Hello, I'm a new guy and I hope, I choosed the correct section.I didn't find anything when searching and have the following question:Is it possible to calibrate the UNI-T UT161E in the voltage range, but in the classic way with a trimmer potentometer (and a reference voltage source)?I ordered the device and have to wait a few days to hold it in my hands and now I'm collecting interesting details.Thank you for every answer and greetings from good-old-Germany!

author: BILLPOD
author_rank: Frequent Contributor
timestamp: January 11, 2024, 02:48:17 pm
content: I wouldn't think a 'BRAND NEW' DMM would need calibration. What is your reference voltage source? And will this be your ONLY DMM? Sorry for answering your question with more questions, but I'm confused.

author: MisterWilli
author_rank: Newbie
timestamp: January 11, 2024, 04:11:11 pm
content: For God's sake, I didn't want to cause confusion! But I'm happy to satisfy your curiosity.As a scientific engineer, I follow the motto: "It's never wrong to increase your knowledge."I don't want to calibrate a brand new device either, I just asked if it was possible.I own multimeters in the 250 - 300 USD class (based on European sales prices) from Fluke and Keysight, it is my first (significantly cheaper) UNI-T device.At my employer I have access to regularly calibrated high-resolution laboratory measuring devices from Keithley.With these I can check a calibrator from Gossen Metrawatt (a German brand), which I could then use for calibration.More would certainly not be necessary with the UNI-T, like my other devices.Since I'm very curious overall, may I ask how this information helps?I suspect that you have a useful answer to my question and I look forward to it.Kind regards to you and the forum members!

author: Gyro
author_rank: Super Contributor
timestamp: January 11, 2024, 04:35:15 pm
content: The UT61E is nice and 'dumb', it has a (not very good quality) multiturn pot for basic DCaccuracyadjust and other pots / caps for other ranges. There's even an adjust for the 10A shunt.Joe Smith did an interesting set of videos on the internals and performance...https://www.youtube.com/@joesmith-je3tq/search?query=UT61E

author: MisterWilli
author_rank: Newbie
timestamp: January 11, 2024, 04:57:40 pm
content: Hello Chris,Thank you for this interesting information.However, this is the UT161E [= 61 + 100] which costs more and, from what I've looked through YouTube videos so far, its hardware is very different from the 61E.Well, in the end I'll be able to take a look at it from the inside in a few days and maybe I'll be wiser!Kind regards, Willi.

author: Gyro
author_rank: Super Contributor
timestamp: January 11, 2024, 05:01:45 pm
content: Doh!

author: Vovk_Z
author_rank: Super Contributor
timestamp: January 11, 2024, 05:32:24 pm
content: As I know 161E and 61E had to be the same DMM (161 and all other +100 is EU certified). But possibly manufacturer changed its design recent years.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: January 11, 2024, 06:02:29 pm
content: Hello again MisterWilliTopic, Your complete reply to my reply satisfied my curiosity. Please post your accuracy and calibration results as I'm sure many here would be interested.

author: MisterWilli
author_rank: Newbie
timestamp: January 11, 2024, 06:21:25 pm
content: Quote from: Vovk_Z on January 11, 2024, 05:32:24 pmI am not shure about it but I will report it later.

author: jackobo
author_rank: Contributor
timestamp: February 11, 2024, 03:45:57 pm
content: Quote from: Vovk_Z on January 11, 2024, 05:32:24 pmUT161E is EU tested and safety approved version of UT61E+ and provides more advanced high voltage input protection than 61E+. 61E is older version and also had EU version, with GS and TUV certifications on the body.Are there real owners of UT161E here, could you measure resistance measuring mode output voltage? The problem is, UT61E (older version) provides 200mV voltage in this mode allowing measuring circuits like transistor>resistor properly. Whereas let say UT61E+ provides ~600mV in resistance AUTO mode thus it opens the transistor base and provides false reading.

author: r6502
author_rank: Regular Contributor
timestamp: February 17, 2024, 12:31:45 pm
content: Hello all, and welcome MisterWilli,I think, you mixed up something: calibration and adjustment. This is a common misunderstanding in the meaning the terms with respect to metrology, even here in this forum.Calibration is only a comparison of the DUT with respect to it's specified uncertainty to a known standard with a smaller degree of uncertainty. The known standard is typical linked to a national standard, when this is done at a calibration lab. The result will be in or out of specification. If the DUT is out of it's specification an adjustment can follow, if needed.So back to your question: what you described is the adjustment process, of the DUT, that follows, when the DUT is out of spec.Some links:https://en.wikipedia.org/wiki/Calibrationhttps://eu.flukecal.com/de/literature/about-calibrationGuido