This meter (well, the near-identical ZT-102) has survived high voltage transients which damaged the Fluke 87V - search YouTube for Joe Smith's tests. So although I'd be the first to say that the CAT ratings are fictitious - as is the case for most cheap (and some not-so-cheap) multimeters - I'd not be too concerned about using the meter to measure mains on the bench. But not in the consumer unit though
There is a PTC, only it's not visible in the supplied images. I've got more detailed images on
my review.
I agree the fuses are a minor pain. The manual says that you mustn't measure current in situations where more than 32V DC could exist which, when you read between the lines, is a tacit admission that these fuses won't necessarily open safely at higher DC voltages. The fuses themselves are rated at 250V AC, but obviously interrupting DC is another matter.
Although I have several of these meters, I still haven't got around to buying spare fuses. A lot of folk on the EEVblog forum have bought wire-ended fuses and chopped the wires off - I've not read of any issues with fit, in terms of diameter. I see that Farnell stock suitable fuses with no wires to cut off, but they are "while stocks last". RS and Farnell appear to have plenty of the versions with wires, but mostly appear to have the "bump" caused by the end caps that you mention - but the Littlefuse 776 series appear to be a better fit, so that'll be worth investigating...
The
BSIDE ZT301 that I mentioned a few times in that recent thread uses conventional 20mm fuses. They come with ceramic types. The AN860B also uses 20mm fuses, but the ones in my sample are glass - I recommend changing those for ceramic fuses.
Overall, I wouldn't say that Fluke fuses are any more "standard" than the 10mm jobs found in the ZT101. A lot more expensive though. A pair of fuses for a Fluke won't leave much change from £20 if you buy them from a reputable supplier. They are widely faked, so avoid the eBay ones. Looking just now, I note that the prices from RS and Farnell are a bit less than the last time I bought some, so that's a step in the right direction.
I've only ever blown a multimeter fuse once. It was the 440mA one in my Fluke 189, and it was in a pretty benign scenario - these fuses are very fast acting. I had a bit of a shock when I looked up the price of the replacement, and that was all the motivation I needed to be extra-careful when using Flukes! That was more than 10 years ago, I'm proud to say