On Mar 29, 12:32*pm, 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.


A low impedance meter actually works better for home electrical
testing. For electronics testing the high impedance meter works
best. The higher the impedance the less the meter itself will affect
the circuit being measured. If you are measuring outlets in your home
you would want the meter to reject currents that are induced into
adjacent wires. If measuring a resistor in-circuit on a PC board in
an electronic device you would want a high-impedance meter so that the
meter itself has little effect on the thing being measured.

An analog VOM meter would be an example of a low-impedance meter, most
DMM's are high impedance (like an old VTVM meter).

(I'm assuming you are asking about the rated impedance of different
meters and not the choices on the selector knobs since you mentioned a
20meg ohm vs 2k ohm meters).