Multimeter..

[Recursion]

I am away at school and while I'm at home I just have a pos Multimeter. I need one while I'm up at school so I guess I should get a good one. Im in Buffalo, NY and the only real place I know if is Sears or online, but well I really need one asap. I keep getting random system restarts.

From what sears has on there website, what do you guys recommend, even though I want a good one, I still don't have a ton of money to spend. keep it fairly cheap. like $170 max. But the cheaper the better.

[jivetrky]

I would recommend this one from Sears:

http://www.sears.com/sr/javasr/product.do?cat=Electrical+Shop&pid=03481438000&vertical=TOOL&subcat=Multi-Meters%2C+Testers+%26+Accessories&BV_UseBVCookie=Yes

Fluke is a great brand for DMM's. And at $100 this is in your price range and a great DMM

[Recursion]

am I better buying a cheap one at sears then a fluke one on eBay. they do seem much cheaper on there.

[jivetrky]

I've had 2 cheapos and both ended up being crapola. I've never used a craftsman, maybe they are OK. But I do know that Fluke is widely regarded as an excellent manufacturer of DMM's, temp probes, etc.

Definitely if you can get it cheaper on eBay or elsewhere, then do that! I'm sure if you look somewhere other than Sears, you will find it cheaper online.

[ThePCGuy]

I use a $3.99 Cen-tech Digital meter from Harborfreight :sn: .

- Jim

[jivetrky]

yeah, one of my "cheapos" is a CenTech from harborfreight, cost like $5-10. I have been using it the last couple of days and found out that it doesn't properly read voltage. I had 2 9v 300mA power adapters, and it was reading them in the 14-15v range. At first I got really scared that they were bad and were going to fry what they were powering. But I figured if both were reading that, the DMM must be crap.

If only I could afford a good new one. :(

[kayson]

I have a $10 dmm from radioshack and it does everything I need it to...

[ThePCGuy]

So far my Cen-tech has been spot on (checked against a higher end craftsman). When I eventually become more aquainted with electrical circuits and such, I'll step up to something better.

[klingens]

I had 2 9v 300mA power adapters, and it was reading them in the 14-15v range.

It's not your DMM that's wrong but it's what cheapo wall warts put out when there is no load at all. unregulated powersupply you know.

There are two reasons I can see to use a expensive DMM: you need displayed voltages to only have 0,1% variance instead of say 1% or you must have better buld quality. Otherwise: go with the 10$ model

[kayson]

Yeah I have an old 9v 300mA adapter thats putting out 12v

[jivetrky]

It's not your DMM that's wrong but it's what cheapo wall warts put out when three is no load at all. unregulated powersupply you know.

There are two reasons I can see to use a expensive DMM: you need displayed volates to only have 0,1% variance instead of say 1% or you must have better buld quality. Otherwise: go with the 10$ model


one was one of those multiple voltage selecting dealies, the other was the one from my old panasonic phone.

I also read several other things, such as the battery in my G7 mouse, a AA battery, and the voltage coming from a DB9 serial cable from my computer. It didn't read any of them at their rated specs...but above it. I think if all of those things were pushing higher, I'd be having a whole lot of issues. :)

[Adak]

one was one of those multiple voltage selecting dealies, the other was the one from my old panasonic phone.

I also read several other things, such as the battery in my G7 mouse, a AA battery, and the voltage coming from a DB9 serial cable from my computer. It didn't read any of them at their rated specs...but above it. I think if all of those things were pushing higher, I'd be having a whole lot of issues. :)

It's not the meter's fault - they are built in a way that will ALWAYS read DC voltage high, depending on the current. That's not a fault of the meter - it's a property of electrical power and the way mm's are made.

More expensive meters, measure true voltage, by adding more sophisticated and expensive circuitry. If you want true RMS voltage readouts, you'll have to get a more expensive mm with that feature.

For reading AC, etc., fairly accurately, you don't need the true RMS feature. The biggest problem with cheap dmm imo is their lag in settling on a final reading (which get's dang infuriating if you have a lot of tests to be made in a short amount of time), and their propensity to drop dead. :)

You select the wrong range, the wrong setting on the dial, they fall over on the bench when you're stretching out the leads to take a reading, etc. -- and Poof! They're gone to join their mm ancestors. :mad:

For my toolbox I use a real cheapo from Radio Shack - worked fine now for a dozen years- yes, it's entirely analog. :) For electronics trouble shooting, testing electrical problems on cars or my truck (lots of DC obviously), it's time for the Fluke. It knows all about RMS for DC circuits, digital, quick, and protects itself well from every wrong turn of the dial I've made, so far (I don't make many).

A good dmm is not an expense if your work/study requires one - it's an investment. Get a good one, and treat it well. Oh, and learn about RMS DC voltage, of course. :)

Adak

[jivetrky]

It's not the meter's fault - they are built in a way that will ALWAYS read DC voltage high, depending on the current. That's not a fault of the meter - it's a property of electrical power and the way mm's are made.

More expensive meters, measure true voltage, by adding more sophisticated and expensive circuitry. If you want true RMS voltage readouts, you'll have to get a more expensive mm with that feature.

For reading AC, etc., fairly accurately, you don't need the true RMS feature. The biggest problem with cheap dmm imo is their lag in settling on a final reading (which get's dang infuriating if you have a lot of tests to be made in a short amount of time), and their propensity to drop dead. :)

You select the wrong range, the wrong setting on the dial, they fall over on the bench when you're stretching out the leads to take a reading, etc. -- and Poof! They're gone to join their mm ancestors. :mad:

For my toolbox I use a real cheapo from Radio Shack - worked fine now for a dozen years- yes, it's entirely analog. :) For electronics trouble shooting, testing electrical problems on cars or my truck (lots of DC obviously), it's time for the Fluke. It knows all about RMS for DC circuits, digital, quick, and protects itself well from every wrong turn of the dial I've made, so far (I don't make many).

A good dmm is not an expense if your work/study requires one - it's an investment. Get a good one, and treat it well. Oh, and learn about RMS DC voltage, of course. :)

Adak


Definitely good to know. But I guess that kinda proves my point that a good DMM is a good idea. (pun not intended) Because, I would think that most of us would be doing more DC work than AC.

But I guess whatever works for any person is the best way to go. If a cheap DMM works, then there's nothing wrong with that. My cheap Cen-tech worked just fine for me up until recently when I started using it for more in depth projects.

And like I said, thanks for letting me (and others) know about the RMS readings. I've seen that marked on other DMM's but didn't really know what it meant. Now I do!