Buying a Digital Multimeter
Buying a Digital Multimeter
(OP)
I'm thinking of purchasing a digital multi-meter.... I'd like to make an economic purchase. Any suggestions? I'm also not sure if I need a 46-Range or what? What does this refer to?
Thanks
Thanks





RE: Buying a Digital Multimeter
TTFN
RE: Buying a Digital Multimeter
Resolution: 3 1/2 digits (counts to 1999 or 3999) are common, 4 1/2 digit will add a bit of a price jump. More than that and you're talking expensive bench type meter. What do you need?
Range is how those counts are used. 199.9 mV , 1.999, 19.99, 199.9 volts full scale. That's four ranges there.
With some meters, you have to select the range, others will autoscale to the correct range.
Ability to measure AC and DC voltage would be eight ranges (four of each). Adding AC & DC current will bring your total to 16 ranges.
Resistance measurement will add another set of ranges to your total.
That's the basics. Then you can get into some more elegant or specialized measurements.
True RMS voltage and current will add a pretty good price jump. Personally, I think it's well worth it.
Other functions you may want: frequency, capacitance, inductance, temperature measurements, transistor checker; all will cost you. Some more than others.
And keep in mind that generally, any meter that can make lots and lots of types of measurements may not be able to do all of them well. A frequency counter will generally have better range, resolution and accuracy than a 3 and a half digit multimeter on its frequency setting.
Some meters (Fluke for one) include measuring seimens. (The inverse of resistance. Useful to measure the quality of insulating materials.) Some meters may have extra high or low range measurements. For example, most hand held meters have resistance ranges that can measure with a resolution down to 0.1 ohm, or up to 20 megaOhms or so (but not at the same time). Do you need to measure much lower than that, or much higher? That will add cost.
Some meters also allow you to log measurements. For example, make a voltage measurement every 10 seconds and store a couple hundred readings that you can recall later. This also costs. Some meters allow a computer interface.
So, think about what you want, need, and can afford. Go to the website of some distributors or manufacturers and see what's available. (DigiKey or Active Electronics as example distributors, Fluke, HP, Tektronix and others make meters.)
RE: Buying a Digital Multimeter
A.
RE: Buying a Digital Multimeter
I agree too with jimkirk. Whatever you get get; "True RMS", a continuity tester(beeper), and a diode test function. Those three extras are pretty much a must as you will eventually regret not having each and every one of them.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
JRaef.com
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Buying a Digital Multimeter
Hey skoggs(MIA) should have some suggestions for you jraef.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
You are probably scaring the OP - that sounds like a portable power analyser, not a multimeter!
TimjTurner: you need to consider what YOU need from a multimeter. Your requirements might be very different to those of a user from a different industry. My industry needs something tough, simple, reasonably accurate and totally reliable as a general hand-held instrument. Fluke's 20 series is a long-term favourite, even with its limitations (no true RMS
An hour spent poking around on the Fluke website http://www.fluke.com/ looking at the different types of meter and their limitations and capabilities will help you work out which functions are "must have" and which are either "nice to have" or "don't cares". Once you have identifed those factors you will be in a much better position to buy a meter. Fluke's technical notes are obviously biased toward their products, but there is a huge amount of general information too. I've no particular allegiance to Fluke other than as a long time user of their products.
One other thought is that good quality meters frequently appear on eBay. You could save a fair bit of money on a meter which would be expensive through regular channels.
----------------------------------
Sometimes I only open my mouth to swap feet...
RE: Buying a Digital Multimeter
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
I like their multimeters. Their scopemeters are a pale shadow of the Tektronix equivalents. Some people love 'em. Just depends on personal preference! Whose multimeters do you like?
RE: Buying a Digital Multimeter
There is a lot said about how necessary TRMS is. Yes, mostly, but not always. Consider measuring current out of a battery charger. What would you use? Mean or TRMS? Why?
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Buying a Digital Multimeter
Can it do watts verse VA?
Also, I wanted to see the unit well, but I can't find a single picture that I can actually read a button on..
Scotty; mostly higher end mutts $100-200 variety. When I get to the office today I'll look.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Buying a Digital Multimeter
Here it is. Picture made for you! Fresh from camera.
I didn't bother with test leads. It is so sensitive that you can just move your fingers across the connectors to get some millivolts to record. The meter is in max/min mode and shows actual voltage in the main display while it shows minimum and maximum voltage so far in the to extra displays. That works also in W mode where you have watts in the main and V plus A in the extra displays. Or AV voltage, you can then have V in main and frequency in one of the extra displays. Forgot what you get in the third display. See why I love it? Have had it for five years or more.
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Buying a Digital Multimeter
We poked fun at the red shields over the sockets not used for the selected range, primarily because the owner of that meter is the youngest in our group and we are opportunists looking for an excuse to tease him. Weeks later someone had a bit of a fright when he measured voltage on a high energy 415V board using the current range. No more laughter about little red shields. Incidentally, that near-miss would have been much more serious if he had not been using fused probes. They are a pain for many tasks because they are large and clumsy. On high energy circuits they might save you from serious injury.
----------------------------------
Sometimes I only open my mouth to swap feet...
RE: Buying a Digital Multimeter
Hey thanks Gunnar! I see. It's auto ranging.
Q1) How fast does it settle on the correct range?
Q2) On the minimum reading is it smart enough to, sort of, figure out what the minimum is after hookup or do you hit the 'clear button' after hookup?
Q3) What's that 4.2V hole on the bottom right?
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
RE: Buying a Digital Multimeter
A1 I have no exact number. Half a second or so. But you can press the MAN button to have a fixed range. I usually do.
A2 No. It ain't that smart. You have to press CLEAR to start a new min/max measurement.
A3 It is for the mains adapter. Power measurements do consume batteries (probably a lot more activity to calculate everything) so a kWh measurement over several days needs external power supply.
Scotty,
I did use those clumsy fused probes earlier. Those with 10 A HRC fuses in them. Never felt comfortable with them. I now use another type, much more like normal test pins. They have 500 mA fuses in them and a current-limiting resistor that avoids high currents. They are marked 600 V 50 kA and are also much lower cost than those 10 A fused ones. There is one little problem, though; do not forget the internal resistance in the test pins if you are measuring resistance. I just remove the pins and use 4 mm banana plug test leads when I do resistance measurements.
And, thanks for that manual link. I have lost my original manual. This new one looks a lot easier to follow. Wow! It is like having a new instrument to explore!
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Buying a Digital Multimeter
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Buying a Digital Multimeter
Fluke does/did have some type of lifetime warranty plan. I killed a Fluke 87 that was around here for years and they fixed it for free. I was quite proud of the fact - it's almost impossible to kill those things. It wasn't very dead though - it just needed some protection components replaced. Typical wrong range or wrong test lead connections don't hurt them. Attempting to measure voltage in a current range requires a new fuse.
I would like these as basics;
Autoranging
AC/DC volts to 1000V
AC/DC Current to 10A
Resistance
Diode
Frequency
Continuity
True RMS
Min/Max capture
CAT III 1000V, CAT IV 600V
Temperature - it it's a good probe
For me, that covers the basics and anything else is a bonus. For you ????.
RE: Buying a Digital Multimeter
Or at least a filter that takes all PWM out of the signal so one can read the fundamental. I know only one meter (a current clamp with V range) that has such a filter. But no DMM.
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Buying a Digital Multimeter
My email is amitjones101@hotmail.com
RE: Buying a Digital Multimeter
RE: Buying a Digital Multimeter
About $40.00 Canadian.
Auto ranging
AC
DC
Ohms/diodes/continuity(beeper)
Capacitance
Frequency
mA
Hold
Relative measurements. Take a sample measurement and subsequent measurements will be given as relative to the sample.
Illuminated Display.
Little led spotlights in the ends of the probes.
Talking. A nice voice gives you the reading, at the push of a button on the positive probe or a button on the meter.
You may also set it to talk every few seconds.
It has a good feel.
This will be my "Kicking around" meter. The meter I can afford to lose, break, have stolen or whatever.
http://do
When I win the lottery, I want a meter like Gunnars.
respectfully
RE: Buying a Digital Multimeter
RE: Buying a Digital Multimeter
RE: Buying a Digital Multimeter
Oh, for heaven's sake! I have seen some truly memorable foul-ups from dummies with DMM's. I certainly would wish that nobody publishes a book encouraging them...
old field guy