Well, the meter survived quite well the torture - thanks for doing this.
For a UNI-T product, overall, I couldn't agree more but not when compared with the better brands I have looked at.
Then again, having the meter modified may have saved it from the total destruction we are use to seeing with this brand. It's not good enough for me to want to invest more time into looking at the brand again. After 13 products, I think we have learned our lesson.
Indeed. The transient test could have swayed you out of the switch test a lot earlier in the process. However, as we stand today, the state of the contacts and PCB held much better than the other single-test brands you did (apart from UEI, of course).
The break of the stands is an unfortunate event that muddles the waters, so it prevents us from saying one way or another: i.e., that UT61E+ has a crap switch or an "above average" one.
A few unknowns, especially due to the dramatic self-healing, but that happened with the other meters as well.
Well, let's be clear. If we are talking about the contacts opening up (>1kohm) some meters have self healed. Cycle3 shows the five worse meters I have looked at. All of these went open before 7000 cycles. It's good to see Keysight in the mix with UNI-T and the free HF meter.
But consider the other five meters in Cycle4. None of these meters ever opened up during the entire duration of the test. Note that even Dave's 121GW with it's cobbled switch and countless contacts hung in there. While Dave's test limited the measurement to 10 ohms, I like being able to see the higher values and trusting the HP bench meter.
Indeed they didn't open, although the cheapest of the bunch (17B+) was the only one completely unfazed during the test cycle. Also, they are Shift-left the price of an UT61E+ (apart from the Keysight, of course), so there is something to be said about bang per buck (something I also commented on Youtube - didn't read yet your reply there).
After 50k the status of its contacts and PCB are quite interesting. No way to compare with the 17B+, but still...
True but again, the wiper contacts were not locked to the knob. How would the meter have held up had the pins not broke? What if they hadn't spec'ed the frequency counter to 200MHz and the meter still had the original components? Would a small ESE event have damaged it?
Yes, the breakoff was quite unfortunate and we don't know
when this happened in the test. If they indeed copied Fluke's patent as mentioned by floobydust above, they skimped on materials or were incompetent in their redesign.
As for the other specs, that is my biggest beef with Uni-T, Aneng and others: they lie through their teeth with regards to CAT ratings (and, in this particular case of the Uni-T, specifications themselves). If they slap a CAT II 300V on their gear, I would have much more respect for them.
Full disclaimer, I have a Uni-T and a pair of Agilents and they are so far holding well while being used with certain regularity for the best part of five or six years - nowhere near 50k operations, obviously. As I mentioned many times before, the Fluke 87V and 179 rotary switches are kings to me: they are the sturdiest and most well put together that I have ever seen. Unfortunately I don't have the capex to put my Agilent meters through a similar torture contraption as I need them for various tasks and, as you could well see, youtube videos do not bring enough revenue to justify such adventure.
Overall, thanks again for doing the test and publishing these results. That is a great advancement for the manufacturers.