Re: Question about buying a multimeter



David Nebenzahl wrote:
On 3/29/2009 4:50 PM Tony Hwang spake thus:

David Nebenzahl wrote:
On 3/29/2009 2:41 PM Jon Danniken spake thus:

"svu geek" wrote:
>
I need to buy a multimeter. I noticed that for the resistance some
have 2000k and some have 20M, which I believe are totally different.
Which one is better to have? Or does it even matter? I'm mostly
interested in testing something that's around 2M. So I don't know if
it matters which multimeter I get.

For resistance measurements, more is better. A short circuit is ideally zero ohms, and it goes up from there.

Practically speaking, you might never need to measure more than 2 MegOhms, which is a high enough value for most uses.

You're confusing the *resistance* range of a meter to its *impedance*. Both are measured in ohms. The impedance has nothing to do with how high a resistance the meter will measure.

On digital meters input impedance is pretty high already. High Z gives more accuracy by not loading circuit under measurement but some times it is not useful for it's high sensitivity. That is why I still have old tank Simpson 260, Fluke, and even an old VTVM when dealing wth high frequency circuit. On top of that o'scope if I need to see something when numbers don't help. Some times also simple test light is enough.

But we weren't talking about that aspect of meters, so you're just further confusing the subject.


Hi,
If I were buying one now I'd go to eBay, look for used Fluke for a good price.
.



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