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Need Advice on Buying a Multimeter

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Never had a problem with the Flukes, but they are a bit pricey. I also have an Amprobe brand DMM that's been to hell and back.

Assuming the meter is quality enough that it won't blow up in your face, the biggest difference I see between cheaper meters and the more expensive ones it the auto ranging function. With the cheap stuff a bit of electrical noise seems to confuse the AR and the range jumps around to the point of being useless. Not a huge deal, you can just use manual ranges, but annoying.

Also, the magnetic strap that some offer is the best thing since sliced bread for field work. :D
 
buy true rms multimeter
 
For normal use I would go with middle range multimeter. I dont know why so many people dont seem to think that there are anything between a POS radio shack or $4 cheapo and a Fluke.

I have to agree with the quality drop in flukes designs. I have heard about it from a number of people who I associate with that the new stuff just doesn't last like the old stuff did. They die or develop problems shortly after the warranty is up.

I wouldn't buy a fluke given that there are so many great other brands out there that have the same and better ratings and warranties for far less cost!

Frying a $100 meter is far better than frying a $500 meter!
 
If accuracy is important, get a Fluke at any price. Otherwise, price is the determining factor. I have several of the same Micronta shirt pocket meters. Some lasted a week, some 20 years. You pays yer money and you takes yer chances......
 
Accuracy typically isn't that important, even the voltage range for most AC motors is +/- 10% Ballpark is good enough. An expensive meter also isn't necesarily going to be more repeatable or accurate just because it's expensive. You do get what you pay for, but some companies will bend you over, there's always a middle ground. Don't buy the Fluke, don't buy the chinese nockoff, find the company out there that has a middle ground meter that isn't gonna break the bank.
 
I personally run a 4.5 digit Metex and a 3.5 digit Wavetek and really like them.
They are my two main work horse meters and are pushing 15+ years old and have been beat, misused, left out in the rain, snow, and sun, for days at at time and still match anyones high dollar Flukes for in use head to head comparisons of accuracy and repeatability. I wouldn't take anything else after having them.

I dont follow what people seem to think accuracy is any way. My Metex reads AC line voltage to 100ths on the 200 volt range and down to 1/100000 of a volt on the 200 mv range. What more do you need? In practical application use thats still 100 times finer resolution than is needed.

If your just needing a good meter for normal day today stuff a good reputable name brand $50 - $100 meter will do you well.

Like I said for me Wavetek and Metex have proven themselves to me to be solid and reliable and both have good world wide reputations. :)
 
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I've been looking at new meters as well. I'd like something with capacitance and frequency.
Craftsman seems to have a lot of features for the money.
Any thoughts on their overall quality?
 
I have a simple Craftsman meter my mother in law gave me for Christmas, was inexpensive and it performs well, for a simple meter I was impressed by the fact that it had a nice rubber/plastic impact case around it that protected it from general abuse pretty well. I've not taken a look at any of their other meters though. The one I got was a basic autoranging small handheld not any advanced features.
 
Velleman got some freq/cap/temp. monitor meters at around USD40. But actually I haven't bothered about this 'velleman' until coming to this forum. Seems they're popular on other part of the world. Guess it'd be good. Frequency-20KHz, Temperature- 1000C, Capacitance-20uF...

I own a very basic 'Mastech' DMM and was not anything more than 6USD when converted. But eventually I'd like to replace it :)
 

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Some after-thoughts...

:rolleyes:Always I come up with a better answer after I study on it for a while....

I use a 4000 count Fluke for field troubleshooting, on instrumentation and computers, where 10 micro-volts IS important. Industrial scales are 0-20mV full scale. I once built a scale with 750,000 (3/4 million) pound capacity. The resolution was 10 pounds. I could tell if someone was out walking on the weigh bridge.....

The comment about general use is spot on, +/- 5% is usually more than sufficient.

My bench meter for calibration is an American Reliance 4-1/2 digit. Both it and the Fluke are "True RMS" meters. RMS is important if you are working with "non-symmetrical" waveforms. For D-C and 50/60 Hz line frequency, standard calibration is quite acceptable.

For the hobbiest, over-range tolerance and internal fusing is important. When the LCD display blows up in your face, the glass shards can draw blood. Not if, but when. It will happen, eventually. The more careful you are, the longer it takes. But it will happen.

High current capacity isn't really important; If your circuit is pulling 7-1/2 amps, light meter leads can get you burned. Use a shunt resistor, say 0.1 ohm and read the milli-volts across it.

Light-weight "pocket" meters are very handy, especially in the field, but I really don't trust them on anything over about 24 volts. Also, look for the cushioned case, with moisture seals. Conductive dust will zap you just as quick as a wet meter. And, you never know when. At least if the meter is wet you know to back out and dry it out.

For power circuits, especially dealing with motors and large inductive loads, an analog meter is more useful. And safer. I keep a Simpson 260, and a vintage Hickock for working on motor controls. Also an (very) old Micronta. From Radio Shack, back when they were still a division of Allied Radio. (before Tandy) But, it stays on the bench. The motion of the needle is useful working with large caps, as well.

Know well that a digital, especially newer models, WILL lie to you on inductive circuits. I have seen it both ways; telling me power was there when it wasn't. Or more important, the full line voltage WAS'T there when it was. At 480 volts, and high horsepower, that is definately not acceptable.

A digital will also tell you a glass fuse is good when it isn't. Use a test light, and NOT one of those neon lamp gizmos. Those things are just plain dangerous.

It has to do with input impedence. The digitals have input impedences in the multi-meg ohm region. Wonderful to keep down loading on sensitive circuits. But, there are places where the 20Kohm per volt loading makes a difference to the better.

And, digitals have quick resolution of RMS, if that is an issue. True RMS analog meters are pricey and slow to stabilize. And sensitive to temperature, as they normally use the "Joule Heating Effect" on a resistor to drive a milli-volt thermocouple.

Since I work with such a wide variety; heavy electrical, analog instrumentation, and computers (analog computers DO still exist), for tool-box use I have a Simpson(260/5), the Fluke(73), and a Square D "Wiggington" industrial voltage tester. The Ideal brand "Wiggy" is nicer and has a fuse tester built in. BUT, I've taken 480 phase to phase across the chest because their leads are not as well made as the Sq.D. (That zap is probably why my mind is so far out in left field:D)

The old man that taught me to troubleshoot at my first mill job carried 2 of the 220 volt shop lamps in series with 3 leads. DC cranes operate from 260-280 volts. That's a little :D heavy handed for the hobbiest but it was what worked for the situation.

Bottom line, there is no single "best" meter. Look at quality more than price. Sometimes it's hard to tell. And unusual conditions will ruin the best of the best. Airline baggage holds are not usually pressurized. When I traveled for Wang, I had to replace my Fluke two-three times a year. The low pressure ruined the LCD display.

This probably caused more confusion than help. But, I do hope it helps.

Bill
 
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