Old thread I know, but thought I'd throw this here for anybody in the future.
I think I've found that Ultimate Lithiums are not good for use in the Extech EX330. With them the resistance auto range would not lock. In fact no resistance range would lock. Swap the batteries out for some part used alkalines (~1.3v) and all seems back to normal. In fact the (rather annoying) NCV function seems to work better as well.
I originally went with the ultimate lithium as I had them sat around, and I know my meters are used little and infrequently enough that having a 10year non-leaking battery in there (well, I've never seen one leak) would have suited my 'work pattern' nicely. I'll consider picking up some more Ikea aaa LADDAs and putting those in.
At least now I might not bin the EX330, which I was seriously considering yesterday. It still has annoyances, and I wish when I got it a few years back I'd seen the Brymen recommendations ;-) I'll work myself up to getting one of those, maybe. I've lost a little bit of faith in the EX330, and if you can't trust your meter then, well, it's not really of use is it!
Annoying things about the EX330 for me then:
- the NCV function cannot be turned off. The manual states 'works in all dial positions' - yeah, even in the *off* position. So, when you can hear the NCV buzzing away in your tool bag as something is pressing on the button, you have to wonder if the meter will still be alive when you next need it :-(
- even though the resistance auto range now works, it is *slow*. So slow I thought it was still broken. You can visually watch it slowly walking through the ranges trying to find a match. It was taking 3-4s to lock on a 3k3 resistor. My old 2nd hand Fluke 73-ii took maybe 0.5s.
Well, I hope some of that helps somebody in the future :-)