Which DMM to use? - Page 1
Forum section: electronics / beginners

author: trilerian
author_rank: Regular Contributor
timestamp: June 10, 2024, 05:22:03 pm
content: The thread title is kind of click bait, sorry...I've done a decent amount of reading on these forums and one thing that I end up seeing a lot of is: I have this dmm as my daily driver and this 7.5 digit dmm for when I really need the accuracy. Or something similar...So my question is, what is the reason for not using the big bad dmm that you spent a ton of money on as your daily driver? Looking through data sheets on dmm's usually will give you a time that the dmm has to be powered up for to be within spec. I understand this as electronics have to warm up and get to their stable operating temps. So if someone wants to be really accurate with their big bad meter that reads 7.5+ digits, they have to let it warm up for awhile before using it, or do you always have it on and just wait for the opportunity to use it?I ask this because I have accumulated 3 bench dmms (we'll not talk about hand units...) over this past year of being in the hobby. And my big bad dmm (only a 6.5 digit, lol) is my favorite dmm to use. There are a lot of features on it that I like and use over my other 2 dmms and is my go to meter. Generally my other meters are only used when I need multiple readings at the same time.Is there a reason I need to change this? Is it bad for my expensive meter to be the one I go to and have running all the time? In my mind, I spent quite a bit on money on this meter, it should not have issues running 16 hours a day and being used.

author: exmadscientist
author_rank: Frequent Contributor
timestamp: June 10, 2024, 05:43:59 pm
content: If you are working at your bench, and you have a nice bench DMM, of course you should use it!The only real risk from leaving them on constantly is that the displays on certain models wear out. The meters themselves usually like it just fine.I typically turn mine off because the accuracy straight out of cold power-up is almost always quite good enough.

author: BennoG
author_rank: Frequent Contributor
timestamp: June 10, 2024, 07:43:44 pm
content: also if you make a mishap with your expensive 6 1/2 meter it is an expensive mishap, e.g. measure mains AC while meter is in ohm range.If you blow up a cheap 3.5 meter that does a lot less pain.And this will happen to everybody some time, or multiple times.Benno

author: BeBuLamar
author_rank: Super Contributor
timestamp: June 10, 2024, 08:07:56 pm
content: A lot of times I need to make measurement not at the bench or even where I can have a convenient outlet so I use the portable DMM with 3.5 or 4.5 digits.

author: Kleinstein
author_rank: Super Contributor
timestamp: June 10, 2024, 08:48:12 pm
content: For many uses there is nothing wrong with using the good meter even for simple tasks - at least if the meter is left on anyway.A simpler meter, especially a portable battery powered one can have some advantages: fast "boot" turn on time, low common moder leakage and common mode noise.The very high accuracy meters tend to not have very good protection and may be an issue with large spikes / high power. Stronger ESD events may damage / degrade a high end DMM over time.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: June 11, 2024, 09:59:14 am
content: Having spent my working life in the electronics industry, and more than 50 years in hobby electronics (mostly radio), I fail to see why any "beginner" would need a multi-digit bench meter. The accuracy is only as good as when it was last calibrated and you are tied to using it on a bench, and it may be less robust than a hand held meter.FWIW, I have a couple of BM235 meters (as recommended by Dave Jones of this blog forum) and a Fluke 177. Both meters are relatively immune to user errors, in the worse case you blow an expensive fuse.SJ

author: Laval
author_rank: Regular Contributor
timestamp: June 11, 2024, 10:16:07 am
content: I guess it depends on what you are doing. Hand-held multimeters are handy. You can bring them close to the circuit you are probing which can be very useful. The high precision multimeters don't always have all the features you may need when troubleshooting a circuit. For example, Keithley 2001 and HP3458A don't have continuity or PN junction test (which you can always do without but still handy). High precision multimeters often need to warmup a bit before they stabilize and using all their accuracy often require a setup (controlling noise, etc). If you have one, of course you can use it but sometimes it's more handy to use a good hand-held multimeter. High precision is often not that important.

author: trilerian
author_rank: Regular Contributor
timestamp: June 11, 2024, 12:21:35 pm
content: Thanks for the replies. I will continue to use my good meter as my go to. Some may question whether or not I need it, I'm not going to die on that hill. I'll just say I already have what I have and I will use it since there is no harm in doing so.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: June 11, 2024, 07:28:51 pm
content: Good Morning Trilerian, I'm curious how you are able to get by with only having 2 meters. How are you able to resist the siren call of 'yet another meter'. I have over a dozen, but I usually pick which I will grab by the function I need to measure. Most meters have at least one feature or function that distinguishes it from all the others. Maybe it has a very fast continuity test, or it has an LED that lights up along with the beeper. Or maybe the diode test has a higher voltage and allows you to test zeners. Or maybe it gives a little beep on the diode test. I have a couple that have a gorgeous display, but it is just average in all other aspects. Or, you will like a particular meter for reasons you can't explain. Such is my UT117C. I've had it for only a few months, but I find myself reaching for it most often. And like you, I have a very nice 6.5 digit bench meter, but I don't turn it on very often. You are lucky you only have 2 meters to choose from.....or are you

author: bingo600
author_rank: Super Contributor
timestamp: June 11, 2024, 07:37:31 pm
content: I'm mostly using my Mastech Bench meter or my Brymen257 for daily work.They both turn on instantly.The 34401, K2015 are only used if high precision is needed.The 58' is mostly used for datalogging.

author: David Hess
author_rank: Super Contributor
timestamp: June 11, 2024, 08:54:29 pm
content: I do not use my best bench digital multimeter for routine stuff because it risks damaging it for no good reason.High resolution bench multimeters often have lower voltage and current limits.

author: aeberbach
author_rank: Regular Contributor
timestamp: June 11, 2024, 10:16:45 pm
content: I have had one good meter for over 20 years. In that time I have bought another couple but generally despise them as they are slow to update, have controls that are less good, screens that are less good, but worst of all they have a continuity beeper that sounds like a sick beetle farting underwater, a pathetic stuttering barely audible bleat that is really not very useful. How do so many meter manufacturers get this wrong?

author: HobGoblyn
author_rank: Unknown
timestamp: June 11, 2024, 10:20:26 pm
content: I’ve got two cheap VC8145 bench multi meters (£130 each) and two £40 - £50 hand held (Uni-t UT61E and Aneng AN870).So none of mine are really expensive, hence if I did blow one up, while annoying, it wouldn’t cost a fortune to replace.I use them all, but the two bench ones are on a shelf at eye level (if I’m sitting upright, not hunched over the desk), if I need a few quick readings, I often find it’s easier to have one of the hand helds next to whatever I’m doing, as it’s far easier just to glance left/right to my handheld than it is to lift my head up and look at the bench ones.

author: trilerian
author_rank: Regular Contributor
timestamp: June 11, 2024, 10:58:04 pm
content: Quote from: BILLPOD on June 11, 2024, 07:28:51 pmWell, my good meter has a touch display which I love, has a rel function which is awesome for when I am using it for current shunts, and when I don't have filters enabled it is a lot faster than my other meters. All these things are a plus. If I am doing anything I consider to be possibly damaging I get out my handheld BM235, because well, everyone on eevblog has one of those, right? I do have a couple of purpose built meters, like a milliohm meter and a cheap hand held LCR meter as well... So the bug got me too, and there are plenty more out there I will eventually get.My good meter, well, I agonized over buying for about 2 months before I finally caved. I read every post I could about it and its very popular 6.5 digit competition, until I finally justified getting it. But I am the type that if I spend the extra for something better, I want to use it not let it sit and look pretty. Maybe one day I will actually figure out how to use it for other stuff too, it has a lot of features...

author: exmadscientist
author_rank: Frequent Contributor
timestamp: June 11, 2024, 11:25:25 pm
content: Okay, sure, an 8½-digit 3458A is not a great daily driver.But I still say that a 6½-digit 34401A is anamazingdaily driver, and is pretty hard to kill (see AoE 3e, §4x.16 if you want to debate).

author: Laval
author_rank: Regular Contributor
timestamp: June 12, 2024, 11:32:25 am
content: Quote from: exmadscientist on June 11, 2024, 11:25:25 pmThis is a great meter. I have a 34410A, pretty close to yours, and I use it as my main on the bench. This multimeter is blazingly fast stable and accurate. It also has all the handy features (continuity, diode) an the ergonomy is great (except perhaps for the fan noise but you get used to it). I use handheld multimeters when i need the meter to stay close (avoid turning my head around too much) or when I need good input protection. As for high precision meters, I only use them when measuring high precision circuits or calibrating another device.As for electrometers and the like, they are specialty equipments.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 12, 2024, 04:08:09 pm
content: 34401a, 34410a, 34411a are very good, cloned vfd's are available, recap if needed and recalibrate and good for many yearsi don't thrust any of the 34461 series ( mcu failures and supply lines failures) and 34465 (who seems more reliable ?)Keithley dmm 6500 etc ....some K2000 series too (reversed schematics) but the unobtanium smd resistor TF245 is a killer if it fail ...

author: Laval
author_rank: Regular Contributor
timestamp: June 12, 2024, 06:25:45 pm
content: Quote from: coromonadalix on June 12, 2024, 04:08:09 pmI didn't know about the 461 which I almost bought instead of my 410A. Good to know.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 13, 2024, 04:23:47 pm
content: not sounding alarmist, but there is a few threads here and there about failures in the meter, if the meter is under the warranty, that's okay ? or not ?but the used price for many stuff is excessive, before covid you had very good prices, snatched a few 34401a for low prices, 1x had a power xformer failure, other needed some recapping, and one was calibrated, and after all theses years, it was pretty solid, still in specs ....bought a 34410a put a cloned vfd for 55$ usd, had to be careful and precise, but worth the price, and now their prices are pffffffffffdepends of your needs, logging ? or other functions ... usb gpib lan ... scan card ....

author: Laval
author_rank: Regular Contributor
timestamp: June 14, 2024, 12:10:39 pm
content: Quote from: coromonadalix on June 13, 2024, 04:23:47 pm34410A is an easy one to recap too. Only 4 or 5 caps to change. Just have to remove the case, the chassis gives you access to both sides of the board. You don't need to tear the whole thing apart.I agree on the price, it's just ridiculous.

author: kevin.gibbs
author_rank: Regular Contributor
timestamp: October 23, 2024, 01:33:59 pm
content: High accuracy is not always necessary; sometimes, mobility is more important. That's when simple multimeters work well. But while you are working at your desk, it is logical to use your favorite device.

author: BeBuLamar
author_rank: Super Contributor
timestamp: October 23, 2024, 05:45:15 pm
content: Quote from: exmadscientist on June 11, 2024, 11:25:25 pmDoes it run on battery? If not then it can't be my daily driver.

author: u666sa
author_rank: Frequent Contributor
timestamp: October 24, 2024, 07:23:31 am
content: Well I have UT61E+ as my daily driver, but I also have B41T+ laying on the shielf, which I'm not using because you can't use two multimeters at the same time, but which I bought because the price was really nice.The only time I use it is to verify something. Like day before yesterday, I was making a video and had to verify amps taken.Hard to say if I would use a bench multimeter if I had it. I don't think it would be compofortable with all the speghetti wires and the reach to switch things. Then there is the why, because cheap-o multimeter does everything just fine.