Re: Multimeter Ohms

Ralph Mowery wrote:
"Peetie Wheatstraw" <peetie.wheatstraw@xxxxxxxxx> wrote in message
news:8t13c49g2kmikdogskq19gqqts2ak28q85@xxxxxxxxxx


I've never really understood about MM readouts for ohms.

I have here a Chinee-Sears digital MM (maybe $15 on sale) and a
circuit that
should measure 450-550 ohms. I set the MM to 2k ohms, the MM reads
say .500.

Is it telling me it measures .5 x 2000 = 1000 ohms? If not, what?

Being as it's digital, shouldn't it report actual integer ohms? More
expensive MM's do this?

Thx,
Peetie

When you set the MM scale to the 2K position, that is the full scale.
It will not read a resistance of a higher value than 2000 ohms and
should show an OL, OR or some other indication you have exceeded the
range, just as an open circuit will show. You could have a 4000
ohm resistor hooked up to the leads and on the 2 K range it will show
as an open circuit. Some meters may have a slight overange and not
top out at exectally 2000 ohms on that scale.

When it shows .500 it is actually telling you that you have a 500 ohm
resistance between the leads.
In other words, the number is the actual resistance in numbers and
you have to place the decimal point in the correct place.

I don't think that's right for an analog meter. If you set the meter to the
1 Megohm range and place a 100-ohm resistor across the terminals, the meter
will read 100 ohms - you just won't be able to tell it. The setting is for
the SENSITIVITY not the allowable range.

Conversely, the setting for reading voltage does imply a maximum range.

It's pretty much the same for a digital meter. The readings will be
accurate, just not precise.


.

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