i am new to the Arduino Platform, i just bought my first Arduino UNO Rev3 board & a basic starter kit, i need some suggestions & recommendations on what type of Multimeter should i buy for my projects?
I have 3 cheap DVMs, inluding a Mastech MS8260 with measures capacitance and inductance.
If you're planning on working with AC measurements, forget about them, and get a DVM that is True RMS, such as the Fluke 114 (and 115, 116, 117, etc), although it is significantly more expensive.
You should keep in mind that the inductance and capacitance measurment on Mastech DVMs have a quite limited range and high error margin, making this feature useless in most cases.
The Mastech MAS830L is a clone of several 830 DVM. Most DVMs with 830 in their model numbers are basically the same thing internally, featuring only external cosmetic differences (and sometimes backlight). They are very simple, very basic DMVs, but quite usable for hobbists that won't be doing much AC measurements (because they aren't True RMS)
If possible, get a Fluke. Otherwise, any DMV will do.
If you're NOT going to get anywhere near household voltages (110V, 220V), go to someplace like harbor freight and get a couple of their really cheap digital meters. http://www.harborfreight.com/7-function-multimeter-98025.html (they frequently go on sale for about half that price...) It's not a fluke, and it's not even safe to use on 440V industrial AC (110V is "marginal"), and it won't have stellar accuracy. But it's almost certainly good enough for almost anything arduino-associated, and having two (to simultaneously measure current and voltage) is more useful than having a better meter. IMO.
westfw:
If you're NOT going to get anywhere near household voltages (110V, 220V), go to someplace like harbor freight and get a couple of their really cheap digital meters. http://www.harborfreight.com/7-function-multimeter-98025.html (they frequently go on sale for about half that price...)
Sometimes, if you wait long enough, you'll get or find a flyer with a coupon on it to get a free one.
westfw:
It's not a fluke, and it's not even safe to use on 440V industrial AC (110V is "marginal"), and it won't have stellar accuracy. But it's almost certainly good enough for almost anything arduino-associated, and having two (to simultaneously measure current and voltage) is more useful than having a better meter. IMO.
I've never had a problem with measuring household voltages using one, but YMMV I suppose; I certainly wouldn't go beyond such a voltage, and I agree that they are perfect for Arduino hobbyist use. Also, don't attempt to measure high currents with them - the wire the leads are made out of vary considerably in quality (I once had some leads with only 4-5 strands of wire in them).
I was using one of these today changing out wall outlets at a friend's house. I find I use this meter 95% of the time. The only thing really missing from it is an audio beep when checking continuity. I missed getting a free one last week in a get one free with any purchase. I've got a couple, but like reading glasses, seems like I can always use some more.
You can build a circuit with two 555 timers to measure capacitance down to a resolution of 0.1pF using your meter on the 200.0mV scale. Use a stable capacitor for C1, a poly or mylar capacitor as annotated.
Hah! I just noticed that I put a note on the top left corner on when Max Headroom was on.
Hi to all, from my point of view a multimeter is something you'll use during a lot of years, my recomendation is to save a little bit of money more, and buy a totally reliable one, from my point of view nothing compares to the multimeters made by Fluke, please have a look.
Yes, Fluke is good but expensive. Save your money towards an oscilloscope! Buy two really cheap meters from the likes of Ebay, they will be accurate enough for most purposes.
I have an expensive bench multimeter (Xerox) that I keep for when I need the accuracy or true rms but 99% of the time I use one of my two Chinese ones.
but these two are the only Multimeters i can get my hands on considering my budget & availability of them at my location.
Get the best one your budget can afford, but the least expensive one should handle most arduino projects. Capacitance is useful if you plan on using grab bag ceramic capacitors as the labeling on them is often hard to read. AC current is useful with home projects.
Hi Russellz, I agree with you, Fluke could be expensive, but one of my Flukes is working since 20 years ago, and I always trust on it, I have bad experiences in the industry with DMMs not reliable at all, never really knowing if high voltage, 250 VAC, were existing or not, for me to look at the screen and know what I'm reading is true is a life warranty, a multimeter for 20 years and more is not expensive at all.
OK, the two meters you cite correspond to about $15 and $10 US. They are probably reasonable quality and if you can afford the better one, by all means.
That said, I have to agree with various other comments here; you can get a meter for less than $5 US which will do the vast majority of what you need to do with Arduinox. I have about half a dozen of these lying around - just like my reading glasses - including in the car glove box or tool box and at work. The alternative is to have one and carry it around everywhere? I don't think so.
I also have a Fluke 87 which is nice. Can't recall where I obtained it second hand.
Other points:
The MS8221A using three AAA cells is very practical. they are generally cheaper to replace than 9V "PP3" batteries and should last longer. In this respect, the Auto Power Off is a very important feature as you are certain to leave it on from time to time and few meters last more than 24 hours turned on - if that.
The MAS830L doesn't look too bad. It has the buzzer function too. It uses the "PP3" battery and does not have automatic turn off. That feature alone may rapidly pay off the difference in price of the more expensive one!
You will very rarely need to measure AC current. If you do, a purpose-built power monitor for the mains which necessarily is "true RMS" and can measure usage of switchmode and reactive loads would be more appropriate - these can be obtained in the $12 to $15 US range.
I use the cheap meters for checking the mains (240+ volts here) - occasionally and very carefully - the most risky parts are the leads.
Capacitance and inductance meters which also test and identify semiconductors using the "Ardumeter" project are available for about $12 US - without a case! They tend to have more appropriate sockets for inserting component leads because it is rarely useful to test in-circuit. I also have a couple of the Electronics Australia ESR meters.
You do not often need the light. Theoretically, for taking mains measurements in dark places.
I have a mix of meters. I have usually had one good meter that is the best I can reasonably afford, and use. Then several very inexpensive pocket meters.
Craftsman meters, IMHO, are garbage. I have two. I just had one begin dying in a dangerous way - it reads low on AC voltage. I opened it up. It has electrolytics with damaged or missing heatshrink covers, chips in ceramic capacitors, bad solder, etc. $70 piece of garbage no better than the free red meters from Harbor Freight.
BTW, never use those cheap HF meters on your house wiring. I opened a few up, there were solder balls and strings of solder everywhere. Some joints were incompletely soldered, some didn't even have solder wetting both the wire and the pad. The fuses are glass, making a joke of the supposed Cat III rating.
And my boss did exactly the failure mode I was most worried about - he had the probes plugged into 10A terminals and connected it to a 240V dryer socket. Fortunately he was holding only the probes, as the meter blew to pieces. The thin wires in the leads could have just as easily have melted and electrocuted him instead.
As far as I am concerned, an oscilloscope is a requirement. Even if you get an analog 20MHz scope, dual trace if at all possible, that's good!
Don't bother with those nano scopes. Smaller than your cell phone screen, terrible frequency response that changes depending on the V/div setting, waste of money.
polymorph:
As far as I am concerned, an oscilloscope is a requirement. Even if you get an analog 20MHz scope, dual trace if at all possible, that's good!
Couldn't agree more. I designed and built my first oscilloscope at the age of 16 using a scrounged radar crt and valves out of scrapped television sets. It worked, although not very well, but taught me a lot.
Yes, those nanoscopes on Ebay look to be a waste of money but if you don't have room for a proper 'scope the BitScope looks to be better.
