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Default Question about buying a multimeter

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.
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Default Question about buying a multimeter

On Mar 29, 2:32*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.


Partly it may be matter of what you will use it for!
For household electrics the cheapest one may be fine.
It's also a matter of knowing how to use it; practically not
theoretically.
If you are measuring batteries, home electrcity etc.it doesn't matter
much.
If you are tinkering or repairing with electronic circuits, it may be
desirable to have one that has a high resistance so that it affects
what one is working on the least.
For example if you put a meter of 2,000 kilohms (That's 2 megs by the
way) across a circuit that itself has resistance of say 2 megs you
will get a wrong reading (a very wrong reading). That's why high
quality bench testers can be 50 meg-ohms, so they have virtually no
effect on what they are measuring.
If testing 12 volts DC for the car, or whether an electric heater of
around 10 ohms is OK, or 115 or 230 volts AC it won't matter!
Megohm = 10^6 or one million ohms
Kilohm = 10^3 or one thousand ohms
Ohm = one ohm
All are measurments in units of resistance to the flow of electric
current.
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Default Question about buying a multimeter

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).

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Default Question about buying a multimeter

"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.

Jon


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Default Question about buying a multimeter

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.


Hi,
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.


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Default Question about buying a multimeter

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.


--
Made From Pears: Pretty good chance that the product is at least
mostly pears.
Made With Pears: Pretty good chance that pears will be detectable in
the product.
Contains Pears: One pear seed per multiple tons of product.

(with apologies to Dorothy L. Sayers)
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Default 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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Default Question about buying a multimeter

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.


--
Made From Pears: Pretty good chance that the product is at least
mostly pears.
Made With Pears: Pretty good chance that pears will be detectable in
the product.
Contains Pears: One pear seed per multiple tons of product.

(with apologies to Dorothy L. Sayers)
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Default Question about buying a multimeter

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.


The real question is: What is the use of the multimeter? If you were an
electronics pro, you wouldn't be asking this question. If you just want
to fix stuff around the house, go cheap. Maybe not $5 Big Lots cheap,
but say $15 or $20 cheap at Walmart or the big box hardware chain
stores. I'd pay more for digital, myself, just for the convenience.





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On Sun, 29 Mar 2009 10:32:59 -0700 (PDT), 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.


The resistance you plan measure, 2M ?, had nothing to do with the
resistance of the meter. All mulitmeters can measure a wide range of
voltages, probably enough for anything you'll want, unless your
intrests broaden a lot. (For example, you need a special probe to
measure the 25000 volts on a color tv picture tube, but you will never
do that. And if you need to see if there's voltage to a picture tube,
you can just put a little neon bulb in a soda straw, and hold it near
the thick wire. If it lights up, you have voltage. )

So I don't know if
it matters which multimeter I get.


Just for the record, on an analog meter and iiuc on a digital meter,
it's 2K or 2meg ohms/volt, ohms per volt. I think that means that the
resistance in the meter circuit is 2K or 2M times the greatest value
at the right end of each analog scale. That is, the resistance
changes for each dial setting. Not sure what it means in digital, but
something parallel.

I hate to like new-fangled stuff, but I do in this case. I think you
can easily learn to ignore phantom voltages in AC current and that is
pretty much the only drawback to high impedance meters. While there
are high-impedance analog meters (Like FET-VOMs) they are quite
uncommon. Most are digital and the advantages of digital are
auto-polarity (no need to get the red and black right when measuring
voltage), auto-zeroing and auto-maximum for resistance measuring, and
for some slightly more expensive meters, auto-ranging (no need to set
a dial to the 2, 20, 200, or 2000 volt scale, etc. It figures it out)

Analog don't and can't afaik have any of these things.

OTOH, analog have the advantage that you can put the meter on
resistance and watch a capacitor charge or discharge. After a while,
I felt I could tell a good cap by the way the needle moved. You can
also watch a discharge with the meter on DC voltage, but iirc for all
but really small caps, it takes too long.


It's nice to have a continuity tester with a buzzer built-in, so you
don't have to look at the meter for this simple task. The very cheap
Harbor Freight meters don't have that, and maybe some others don't, so
if you want that, check if it has it.



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On Mar 30, 2:59*am, mm wrote:
On Sun, 29 Mar 2009 10:32:59 -0700 (PDT), 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.


The resistance you plan measure, 2M ?, had nothing to do with the
resistance of the meter. * All multimeters can measure a wide range of
voltages, probably enough for anything you'll want, unless your
interests broaden a lot. (For example, you need a special probe to
measure the 25000 volts on a color tv picture tube, but you will never
do that. *And if you need to see if there's voltage to a picture tube,
you can just put a little neon bulb in a soda straw, and hold it near
the thick wire. *If it lights up, you have voltage. * )

So I don't know if
it matters which multimeter I get.


Just for the record, on an analog meter and iiuc on a digital meter,
it's 2K or 2meg ohms/volt, ohms per volt. I think that means that the
resistance in the meter circuit is 2K or 2M times the greatest value
at the right end of each analog scale. *That is, the resistance
changes for each dial setting. *Not sure what it means in digital, but
something parallel.

I hate to like new-fangled stuff, but I do in this case. *I think you
can easily learn to ignore phantom voltages in AC current and that is
pretty much the only drawback to high impedance meters. * While there
are high-impedance analog meters (Like FET-VOMs) they are quite
uncommon. *Most are digital and the advantages of digital are
auto-polarity (no need to get the red and black right when measuring
voltage), auto-zeroing and auto-maximum for resistance measuring, and
for some slightly more expensive meters, auto-ranging (no need to set
a dial to the 2, 20, 200, or 2000 volt scale, etc. *It figures it out)

Analog don't and can't AFAIK have any of these things.

OTOH, analog have the advantage that you can put the meter on
resistance and watch a capacitor charge or discharge. *After a while,
I felt I could tell a good cap by the way the needle moved. *You can
also watch a discharge with the meter on DC voltage, but iirc for all
but really small caps, it takes too long.

It's nice to have a continuity tester with a buzzer built-in, so you
don't have to look at the meter for this simple task. *The very cheap
Harbor Freight meters don't have that, and maybe some others don't, so
if you want that, check if it has it.


So: With that overload of technical information by some very
knowledgeable posters it comes back to; "What do you want to use it
for?".

If just to test household stuff a reasonably cheap digital display
meter under $20 probably OK.

Learn how to use it, keep the internal battery (replaced) although
they last a long time. Although some/many digitals will shut
themselves off after a few minutes to conserve the battery, anyway.

Check that it has, or make good test leads. The sort that have
substantial rubber over a spring clip are good, so fingers don't have
to touch metal clips contacting possibly live wiring. An extra lead
and/or extension can sometimes be helpful and can be stored in the
same case with the meter.

Make sure electric power to a circuit IS turned off before using the
ohmmeter scale .... that's the one where the meter is most vulnerable
and is using it's own internal low voltage battery to test a 'dead'
circuit. You don't need to hook that setting of the meter,
inadvertently, to say a 115 volts wall outlet and blow the proverbial
you know what out of the meter!

However many do have a special small protective fuse (usually a few
milliamps) inside and some even provide a spare fuse! Resist the
temptation to 'fix' the fuse with Al foil (unless very temporarily and
you know exactly what you are doing) because next time one makes a
mistake (and we all do occasionally!) It's very easy perched on an
awkward ladder with cramp in the bad left leg to forget that you were
just testing for continuity with the ohmmeter setting; and then touch
it on 115 or 230 volts ...................... darn!!!!!!!!! That may
very well damage the meter!

Congratulations to the OP for asking though.
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Default Question about buying a multimeter

Bert Byfield wrote:
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.


The real question is: What is the use of the multimeter? If you were
an electronics pro, you wouldn't be asking this question. If you just
want to fix stuff around the house, go cheap. Maybe not $5 Big Lots
cheap, but say $15 or $20 cheap at Walmart or the big box hardware
chain stores. I'd pay more for digital, myself, just for the
convenience.


The $3-4 harbor freight cheap is OK too.


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stan wrote:
On Mar 30, 2:59 am, mm wrote:
On Sun, 29 Mar 2009 10:32:59 -0700 (PDT), 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.


The resistance you plan measure, 2M ?, had nothing to do with the
resistance of the meter. All multimeters can measure a wide range of
voltages, probably enough for anything you'll want, unless your
interests broaden a lot. (For example, you need a special probe to
measure the 25000 volts on a color tv picture tube, but you will
never do that. And if you need to see if there's voltage to a
picture tube, you can just put a little neon bulb in a soda straw,
and hold it near the thick wire. If it lights up, you have voltage.
)

So I don't know if
it matters which multimeter I get.


Just for the record, on an analog meter and iiuc on a digital meter,
it's 2K or 2meg ohms/volt, ohms per volt. I think that means that the
resistance in the meter circuit is 2K or 2M times the greatest value
at the right end of each analog scale. That is, the resistance
changes for each dial setting. Not sure what it means in digital, but
something parallel.

I hate to like new-fangled stuff, but I do in this case. I think you
can easily learn to ignore phantom voltages in AC current and that is
pretty much the only drawback to high impedance meters. While there
are high-impedance analog meters (Like FET-VOMs) they are quite
uncommon. Most are digital and the advantages of digital are
auto-polarity (no need to get the red and black right when measuring
voltage), auto-zeroing and auto-maximum for resistance measuring, and
for some slightly more expensive meters, auto-ranging (no need to set
a dial to the 2, 20, 200, or 2000 volt scale, etc. It figures it out)

Analog don't and can't AFAIK have any of these things.

OTOH, analog have the advantage that you can put the meter on
resistance and watch a capacitor charge or discharge. After a while,
I felt I could tell a good cap by the way the needle moved. You can
also watch a discharge with the meter on DC voltage, but iirc for all
but really small caps, it takes too long.

It's nice to have a continuity tester with a buzzer built-in, so you
don't have to look at the meter for this simple task. The very cheap
Harbor Freight meters don't have that, and maybe some others don't,
so if you want that, check if it has it.


So: With that overload of technical information by some very
knowledgeable posters it comes back to; "What do you want to use it
for?".

If just to test household stuff a reasonably cheap digital display
meter under $20 probably OK.

Learn how to use it, keep the internal battery (replaced) although
they last a long time. Although some/many digitals will shut
themselves off after a few minutes to conserve the battery, anyway.

Check that it has, or make good test leads. The sort that have
substantial rubber over a spring clip are good, so fingers don't have
to touch metal clips contacting possibly live wiring. An extra lead
and/or extension can sometimes be helpful and can be stored in the
same case with the meter.

Make sure electric power to a circuit IS turned off before using the
ohmmeter scale .... that's the one where the meter is most vulnerable
and is using it's own internal low voltage battery to test a 'dead'
circuit. You don't need to hook that setting of the meter,
inadvertently, to say a 115 volts wall outlet and blow the proverbial
you know what out of the meter!

However many do have a special small protective fuse (usually a few
milliamps) inside and some even provide a spare fuse! Resist the
temptation to 'fix' the fuse with Al foil (unless very temporarily and
you know exactly what you are doing) because next time one makes a
mistake (and we all do occasionally!) It's very easy perched on an
awkward ladder with cramp in the bad left leg to forget that you were
just testing for continuity with the ohmmeter setting; and then touch
it on 115 or 230 volts ...................... darn!!!!!!!!! That may
very well damage the meter!


In my experience, testing on the amp ranges is where the greatest risk to the
meter comes in.


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On Sun, 29 Mar 2009 10:32:59 -0700 (PDT), 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.



k stands for 1000
M stands for 1,000,000

For 2M (or 2 million), set the dial to 10M (or slightly higher). With
a digital readout, all you are doing is moving the decimal point. I
bought a Radio Shack multimeter 25 years ago, still going strong.
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I own several of the cheap HF ones. Far as I can tell, they
work just fine. They go high enough voltage to do AC line
current. And enough DC amps to test flash lights. Works for
me.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Bob F" wrote in message
...

The $3-4 harbor freight cheap is OK too.





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I've fried several Fluke fuses, at about $12 a pop (yes,
they do pop when they blow). Finally decided to use my $4 HF
meter whenever possible. At least their pops are cheaper.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Bob F"
wrote in message ...

However many do have a special small protective fuse
(usually a few
milliamps) inside and some even provide a spare fuse!
Resist the
temptation to 'fix' the fuse with Al foil (unless very
temporarily and
you know exactly what you are doing) because next time one
makes a
mistake (and we all do occasionally!) It's very easy
perched on an
awkward ladder with cramp in the bad left leg to forget
that you were
just testing for continuity with the ohmmeter setting; and
then touch
it on 115 or 230 volts ......................
darn!!!!!!!!! That may
very well damage the meter!


In my experience, testing on the amp ranges is where the
greatest risk to the
meter comes in.



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"David Nebenzahl" wrote in message
s.com...
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.


No, the OPs question is concerning the upper limit in resistance
measurements, *not* the meter's impedence.

I think you might want to reconsider who is confused here.

Jon


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"Stormin Mormon" wrote in
:

I own several of the cheap HF ones. Far as I can tell, they
work just fine. They go high enough voltage to do AC line
current. And enough DC amps to test flash lights. Works for
me.


first one I bought read a 1.5v battery at 1.8V,very inaccurate.
the 2nd tested better.

plus,they are only 1 Megohm input impedance;most DMMs are 10 Megohm,less
circuit loading.

--
Jim Yanik
jyanik
at
kua.net
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Stormin Mormon wrote:
I've fried several Fluke fuses, at about $12 a pop (yes,
they do pop when they blow). Finally decided to use my $4 HF
meter whenever possible. At least their pops are cheaper.


If you are measuring on circuits with high available current you might
appreciate the Fluke fuse. Particularly on a residential service and
many commercial/industrial locations you want a meter that is "category"
rated for the hazard of the location. Fluke will be rated (may not all
be rated for the most severe). I wouldn't bet HF is. You could wind up
wearing the meter. Fortunately that is not much of a hazard in a house
except the service panel. If you are using a meter for work it could be
an OSHA issue.
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Jon Danniken wrote:
"David Nebenzahl" wrote in message
s.com...
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.


No, the OPs question is concerning the upper limit in resistance
measurements, *not* the meter's impedence.

I think you might want to reconsider who is confused here.


I was thinking that several people were confused.




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Default Question about buying a multimeter

Jim Yanik wrote:
"Stormin Mormon" wrote in
:

I own several of the cheap HF ones. Far as I can tell, they
work just fine. They go high enough voltage to do AC line
current. And enough DC amps to test flash lights. Works for
me.


first one I bought read a 1.5v battery at 1.8V,very inaccurate.
the 2nd tested better.


Mine does that when the battery gets low. So does my Fluke.



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I suspect the HF meters also have fuses. What irritates me,
is that the fuses are twelve bucks each. I can buy the glass
car fuses for under a buck each, and the plastic push in
fuses, also under a buck. However, with the Fluke meter,
only a Fluke fuse will fit.

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"bud--" wrote in message
.. .

If you are measuring on circuits with high available current
you might
appreciate the Fluke fuse. Particularly on a residential
service and
many commercial/industrial locations you want a meter that
is "category"
rated for the hazard of the location. Fluke will be rated
(may not all
be rated for the most severe). I wouldn't bet HF is. You
could wind up
wearing the meter. Fortunately that is not much of a hazard
in a house
except the service panel. If you are using a meter for work
it could be
an OSHA issue.


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Default Question about buying a multimeter

Stormin Mormon wrote:
I suspect the HF meters also have fuses. What irritates me,
is that the fuses are twelve bucks each. I can buy the glass
car fuses for under a buck each, and the plastic push in
fuses, also under a buck. However, with the Fluke meter,
only a Fluke fuse will fit.


Having a fuse does not mean the meter won't explode on a high capacity
circuit.

Glass fuses used in a car are probably rated 32V. The same size ceramic
body fuses might be rated up to 250V. None of them have an adequate
current interrupt capacity (for a short circuit). Buss FRN fuses are
rated for circuits with a source current capacity of 200,000A. That is
different from the fuse current rating, which might only be 20A. The
source current capacity ("available fault current") for a house is
probably 5,000-10,000A.

Fluke fuses are high interrupt capacity.

--
bud--
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Default Question about buying a multimeter

"Stormin Mormon" wrote in
:

I suspect the HF meters also have fuses. What irritates me,
is that the fuses are twelve bucks each. I can buy the glass
car fuses for under a buck each, and the plastic push in
fuses, also under a buck. However, with the Fluke meter,
only a Fluke fuse will fit.


I just opened up my HF DMM(no-backlight model),and it has a 5x20mm fuse.

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