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by mikewarot 974 days ago
When you get up to buying meters, the main advantage of Flukes is that you can accidentally put 500 volts into them, and they survive it. When soldering, it's important to wear Jeans, or other heavy non-plastic full length pants.
4 comments

Counterpoint: The IC at the heart of basically every cheap meter is a clone of the IC in an old Fluke DMM

https://www.pa3fwm.nl/technotes/tn27a-voltmeter.html

Honestly I would say cheap out on the DMM and splurge for a good oscilloscope, you get much farther with that.

But, I'm someone who doesn't do high voltage much, or really at all.

It's also possible to cheap out on the meter while still getting a quality product. I like to look here for good reviews/tests of multimeters: https://lygte-info.dk/info/DMMReviews.html
Something I've learned by looking at "clones" of my own products is that it's not a copy unless it copies my component sources, manufacturing, and quality standards.
so much this. Also, (1) if you are laying with 500V you should be careful. (2) cheap DMM will typically also survive (ask me how I know) (3) You can destroy 10 cheap DMM before is more rentable a durable Fluke
I am a fan of the grey market Fluke 17B+. You get many of the features of the high end Flukes like the 87V without the high cost. They are my go to for non critical lab measurements.
I would suspect the clamp diodes / protections would be external to the IC?
Right, I agree that if you're doing HV or need high accuracy, don't cheap on the DMM, otherwise I do think cheap DMMs are good enough for a lot of things and that being able to see the waveform is often more useful than a perfect static measurement
90% of the time when I'm using a multimeter, I'm just doing continuity checks anyway.
Yes, and while we're talking about probing, my favorite DMMs by far are the pen shaped DMMs because one hand holds both the DMM and the positive probe; small, no flat surface needed and always easy to read the screen. No more putting the DMM down on something and holding the probes on while craning my neck to read the DMM, pick up the DMM to move to another location, repeat, so tiring - I tried a pen DMM a few years ago on a whim and I'm always going to use a pen DMM now on.
I never tried the pen version. I actually have a very nice bench DMM that I picked up used for a good price. It's a bit of a "pearls before swine" piece of equipment in my hands, though. I've literally never needed the precision it has, or have done 4 wire measurements, or recorded a series of measurement over time, etc. But I enjoy knowing that I can if I ever need to.

That DMM gives me a similar convenience to what you describe, but I am almost never using a multimeter anywhere but on my bench -- that probably matters a lot.

You can put that into other quality meters as long as their CAT rating is sufficient and was verified by a reputable testing lab (Underwriter Labs, TÜV, etc.). Fluke isn't the only player in town with quality meters.

Also don't skimp on the meter, buy something decent. There is a lot to be said about the real life and noticeable differences in cheap and quality meters when testing or repairing electronics but in the realm of embedded device hacking I particularly found the following features handy:

- A high speed voltage bar at the bottom of the instrument which tells you if a voltage is indeed stable. You can detect the TX pin of serial lines with that. Cheap meters may have that bar but the update speed is way too slow to be useful

- A high speed and loud continuity tester. Many cheap meters (and some expensive as well) have a large delay between shorting out the leads and the buzzer going off. That's rather annoying when you can't make good contact long enough (also see below for test leads).

After working with a cheap meter for a while (Uni-T) I went for a Brymen BM869s and never looked back.

Also get yourself some high quality pointy, hard gold coated test leads. I personally can wholeheartedly recommend the Probemaster 8000 series.

I’ve fried my 3D printer board once because of using a cheap meter. My good meter was out of reach so I grabbed a closer dirt cheap one to measure the output of the 24V bed. Instantly shorted my board and welded the leads to the screw. Long story short, don’t cheap out on multimeters.
Sounds like you tried measuring voltage while your meter was set to measure amperage
I'm a beginner here, but I want to assume that if it was enough to weld it, the cheap meter wasn't the problem.
What exactly happened there, and why do you think it wouldn't happen with a more expensive meter?
My fluke has a fuse on the ammeter.
Yes, unfused 10A range would have been my guess, but if device under test doesn't have short-circuit protection, it might as well die during the few tens of milliseconds that the fuse needs to heat up and blow, as well as a user error to be measuring voltage with switch in current measurement position.
I've never had solder come anywhere near my clothes when soldering electronics.
I’ve seen more than once people tinning their solder irons by add some solder and flicking the solder onto the floor hard.
I did that for many years, and even hit my bare legs or feet a few times. But the solder cools really fast, and doing that doesn't cause a great deal of pain or damage. Just enough to remind you to be more careful.

These days, I flick the solder onto my soldering mat instead.

Yet :-)