First off you need at least TWO meters. How else can you know if your meter works and gives correct readings unless it agrees with some other meter?
Next for this kind of work you don't need a lot of precision. You just need to see if there is "about 24V" on the power lines and even 10% accuracy is good enough for simple diagnostics. If you own several meters yo don't even cars about reliability so much, if one fails you still have a a couple more. So, It's OK to use those free meters that Harbor Freight gives you when you make a$10 purchase. They are better low end but I have at lest four of them and I test their calibration and they are not bad. The build nullity is nothing compared to my Fluke meter. I also just bought a used HP meter. It has 6 digits and is very easy to calibrate and has A feature that most hand held meters lack: It can do 4-wire resistance measurements so that the resisters of the test leads is accounted for. This allows you to measure way down to mili-Ohms. You can use this to test transformers or to measure the resistance of a few feet of wire. These are discontinued so the only source for is eBay. www.keysight.com/...34401A... <http://www.keysight.com/en/pd-1000001295%3Aepsg%3Apro-pn-34401A/digital-multimeter-6-digit?cc=US&lc=eng> SO for basic debugging I'd suggest at least one "good" meter and s few backups (which are either way or free) But for general design some more advanced debugging you have to have an oscilloscope. New digital scope are SO MUCH BETTER then used ones that I can not longer recommend buying used unless budget is real tight For your one god meter it can be a bench type, use HP DMMs is a great value. Used Fake is good also. These are build so well that even used ones will last "forever" and calibrated Calibration is the next issue. It does no good to have 3 digits in the display to the meter reader 20% "off". A New Fluke meter is hold factory calibration for a year or two. Voltage standards suitable for meter calibration are available on eBay at all different price points starting at $5 and doing way up. All user manuals are available on-line for all name brand meters, even the free Harbor Freight ones. Download and read there BEFORE you buy On Sun, Jul 9, 2017 at 9:07 PM, David Berndt <[email protected]> wrote: > Apologies, this might be slightly OT, but I imagine we all use a > Multi-meter a few times a month in our EMC related work. > > It seems my Micronta 22-174b has given up on life, or has suffered a brain > injury at the very least. After not using the meter for about 3 weeks I > dusted it off and was double checking some wiring for a 24v servo brake, > everything went fine, there was no funny event, no smoke, no fire, not even > any brimstone, but the meter didn't read 24v on the 24v line, more like > 19v, and I notice the ohm mode reads 32ohms all the time, even when it > should be displaying open circuit. > > Nothing internally seems amiss, no obviously blown traces, componenents, > no burnt smell. Board says 1992, I guess 25 years is enough, maybe it's > time to consider a new unit. > > Soooo... Anyone have any recommendations for a hobbyist level meter. > > > Dave > > ------------------------------------------------------------ > ------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
