I'm going to do simultaneous
measurements with a very nice expensive
on a fluke and then I also have myself a
$10 craftsman one that I picked up just
for this video so you're welcome and
we're going to work with both of these
side-by-side so the first thing I'm
going to do is just give a quick
comparison between the to denote how to
properly use them and why someone would
pay 150 to 400 for a fluke multimeter
here's a different fluke one that works
and why if you just want to measure a
couple things it's okay to get one of
these it's really not a big deal
especially if you're just starting out
or if you want to do a couple
measurements maybe you're installing a
ceiling fan and you're not quite sure
whether that brick or is really off or
not I've seen breakers that show off and
still have power flowing through them so
I'm going to open this one and then
we're going to do a quick comparison and
then we're going to get straight to it
alright so which is small time meter
well the one thing to notice is and this
is really indicative of all economical
or cheap meters is that they have what
seems to be more options if you're not
familiar what you're looking at because
you look at this more expensive one here
and it looks like hey okay it's it's
less words and you know perhaps it does
different functions but it's simpler
right maybe doesn't do as much then you
look at this one look wow look at all
these different ranges look what it can
do well this meter doesn't automatically
Zone in or automatic range what voltage
you want to measure you have to know
that somewhat ahead of time you're not
going to damage it it just won't give
you a correct reading that's all that's
all the difference as far as why this
one has between 600 and 200 millivolts
and you know this one here when it comes
to measuring DC take a look it just says
V it doesn't say anything else but that
so that's an important
reason why you may pay more for one of
these meters just because you don't have
to play around with for the most part if
you're just using a multimeter for
example you're installing a ceiling fan
or you're replacing a power outlet or a
septic Oh
you know these work pretty well if
you're looking for more precise
measurements obviously this might not be
the way to go if you're thinking about
using the multimeter a lot not just once
every you know month or so then I
definitely want to make sure you
probably grab yourself one that's bit
more industrial this for example may not
be as efficient in using the batteries
that you put in so this may only last a
couple hundred hours maybe this will
last another one lasts even more this
one may not have auto shutoff certainly
the ratings for electrical properties
resistance how much current it can hold
aren't going to be as high as something
like this in fact you can you can tell
for example right here this is a
category two okay now when we look at
this meter here it's talking about a
category four and category three
depending on what voltage level you're
dealing with 600 volts or a thousand
volts again this is a ten dollar
economical version you basically if you
want to measure voltage DC direct
current for example you want to measure
battery voltage then you would turn to
for example up to 20 volts and you would
measure it and you would connect the com
this is the central one and since you're
measuring voltage resistance maybe you
want maybe the internal resistance of a
battery if you want to measure the
resistance of a wire or you want to see
if the wire is broken this is where you
would go for something like this do you
want to measure a resistance of a
resistor there again that's what you
would use that for this test a diode
also beeps when there's connectivity
this one outputs voltage so this is why
this requires a 9-volt battery in order
to properly test the diode you need that
this one has a built-in feature
specifically to test a 9-volt battery or
1.5 volt battery it's
possible that this multimeter could be
putting a small load on these and
potentially giving a more accurate
reading than for example moving it up to
you know two volts over here
I don't know we can check that later now
the reason why that's gray is right here
saying if you want to measure current
you keep calm where it's at but you move
the voltage home and Milly answers to
here and the reason why there are two
basically has to do it the way it's
fused with these two connected and
you're measuring something like a
battery or small circuits maybe you're
trying to measure a fuse that's fine
we're measuring a small circuit with
power on that's what you need current
for right then this is okay but if you
take a close look you need to read
because what it says here is 200 milli
amp max right that's point 2 amps max
that you can take where you'll blow the
fuse out and this won't work if you want
to measure a current that's higher than
that up to 10 amps then you need to use
the calm and the 10 ampere into can
disconnect from here and connect to here
this 10 amp has an internal fuse and
this circuitry for this today should be
as separated away from the
microprocessor and the internals as
possible so that way if this blows it
doesn't affect the multimeter it doesn't
play with this because it's so much
current running through it doesn't
destroy it that's why they're separated
here okay now for comparison when we're
dealing with amperage
this one you would you would turn to
milliamp and if we zoom in real quick we
can see again we connect to calm here
just like we did with this one so this
one had to come here so for this
multimeter when we're talking about
measurements come here
milliamp here anything greater than 200
milliamp you would need to use this one
this is again just your measuring
current and be very very cautious about
keeping consistent with these readings
this is 10 a.m. for 30 seconds max okay
and this basically states that don't
just continue leave this measuring
current and think that it's okay for a
half hour you're going to blow this and
potentially blow this entire thing just
because it's cheap and I'm not sure how
much I would trust really how much I
would trust putting 10 amps is that is a
lot of juice at any rate when we go to
here this fuse portion up to 400
milliamps now this doesn't make it
better because the other one was 200
milliamps in this is 400 millions it's
just the way that this is designed and
again you see that there's a 10 amp here
up at 10 amps max now there's no time on
here that's something you need to look
at the manual for just because there's
no time doesn't mean that you can put 10
amps through this all day and all night
and expect that it's not going to be an
issue because 10 amps again is a lot of
juice the 400 milliamp or the small
milliamp rating in our economical
version as well as our voltage and our
resistance reading were all combined in
one okay and the high current was
separate
with this multimeter again this is a bit
more expensive one we see that they have
completely separated a circuitry to
measure mil amps amps voltage currents
and diodes so they've separated them
again probably more for numerical
finesse you want to make sure that you
get better resolution and to do that
sometimes it's just better to an easier
to separate the circuitry so that's the
difference there one other difference
that I should mention is that the probes
are certainly going to be different in
addition to having different category
rating the wires for example may not be
as great quality the tips may be of just
may have nickel or some type of metal on
there that can easily chip and in that
you know that could affect a reading
later on if it starts to peel whereas if
you have a bit more expensive probes you
may not experience that for example
these probes right here they're category
three for a thousand volts and category
four for 600 volts and this these can
handle 15 amps max so just order caution
if you're going to play around make sure
that whatever probes come with the
multimeter and you go that one you
wouldn't want to switch these probes
throw them on this multimeter and then
expect the same performance you would
notice you know it may be even
detrimental since these are category
three and these can be kept up to
category four of a thousand volts these
can only handle 600 volts so don't mix
and match they're not like shoes and
outfits at any rate so here we go we're
going to do something simple we're gonna
first we're going to measure a battery
so batteries are DC so we're going to
take our fluke
we're going to tell it we want to DC it
says auto range
hence wives have been partially more
expensive for this one since we're
measuring a battery we want to select
the range so we're going to say right
around 200 millivolts or just two volts
and let's go ahead and measure it so
we've got our trusty industrial battery
here move there we go with my cell phone
this so it's reading right around one
point to one point seven volt flying
back and forth a little bit now when I
use my little fun one let's take a look
at how it performs
again I'm connecting the negative and
here's the positive reason it shows 1615
because I showed where I selected 2,000
millivolt if I raise it up to just
between 20 volt now I'm getting one
point six two volt so you're not going
to damage the multimeter if you go way
over right when you go way under
it's not going to damage it but your
readings aren't going to look correct
and most of the time you can just feel
like clearly my battery's not 1613 volts
so there you go so you can see the
decimal point at the 200 you can see the
decimal point at the 20 the difference
between these two and you get better
resolution if I want to measure up to
200 volts you see that decimal point
moves back measure conductance I want to
see if something is conductive and you
can do that a couple ways some of the
readings actually make a tone other ones
you can just use the own so I'm going to
keep everything where I met since I'm
measuring ohm and what I'm going to
measure conductance opposite is a piece
of tape and I know that sounds kind of
odd but this is metallic tape and for a
project I actually use this as a lead I
was making a circuit board and I cut out
a couple patterns since I was using low
current and I was you know basically I
was using this as a wire even though
it's just you know fancy sticky tape so
let's say you didn't know whether it was
conductive because initially I didn't I
thought maybe there was some type of
plastic over this some type of polymer
there you go very very low resistance
so let's take a look if I put it on this
tape it jumps a little bit but that's it
so this tape is conductive so again I
was able to use my multimeter for
something that you wouldn't typically
think hey let's see if my tape is
conductive but indeed it is and as I
said you can use this for leads for a
circuit board if you want current to go
around something you could use it for
that anything you want since it's it's
it's very flexible now what about our
craftsman over here what are we going to
how is this one going to work well let's
take a look
since I'm measuring ohms I'm going to
just bring it down to 20k it doesn't
matter again you're not going to break
if you go over under but for our sake
let's just move it to 20k the middle and
then play around with whether we think
it should go up or whether we should go
down so we're going to going to connect
them right here so if you want to get
more specific if you want to see more
resolution we can just move it down now
we get a little bit more resolution now
we get even more because we have there
look of our period is that so we see 1.0
3.2 I mean it's jumping around as I'm
moving these leads because this isn't
perfectly flat and and for other such
reasons but adds for all really intents
and purposes this is a conductive wire
people parrot probably best nut homes
for resistance and so what I have here
is a resistor I don't know the value of
it so I just measure the value of it
okay so instead of seeing zero now we're
seeing one that means it's perfectly
conductive right well no because look
we're at 200 ohm our resolution is wacky
it's what I mean it's way too low so
let's move it up one this is 1000 but
1000 what so let's move it up to 20 K so
it's between 0.99 and 1.0 kilo so it's 1
kilo ohm resistor now we can certainly
verify that by so it's already at the
ohm reading know if that do anything so
let's go ahead and try it again
and I believe I was touching it before
so one point zero zero two kilo ohm
exactly what the other one stated so
perfect measuring resistors all right so
let's measure the voltage with this guy
when we're going to use this one first
all right so we've got our we've got our
two probes it doesn't matter since it
was measuring AC and it alternates back
and forth between positive negative
negative positive doesn't matter which
end you put in what does matter though
if you want accurate readings is what
setting you choose on here since we're
measuring voltage get knot current so it
stays where it's set that's what the V
is for we're going to measure voltage
and in the u.s. voltage is 120 right
guys voltage alternating current and
right around 200 that's what we would
expect to be it's going to be you know
120 so let's go ahead plug them right in
and nothing
they really disadvantage is that you
have to select your own and if you're
not paying attention if you looked at
this and you should voltage AC 200 I
don't know that you know most people
would say okay that that's it's it's
dead there's nothing in here if they
went to 600 then all suddenly 121 volts
and to be frank this is a problem okay
200 volts I don't think they should have
used that system of metrics knowing that
people are going to probably use this to
measure AC power of outlet C electrical
receptacles I think this was again a bad
design on their part because a lot of
people may assume hey it's a 120 volt
this is 200 volt right it's greater it
should show but it doesn't be very
careful
go up one more if you're not sure it'd
be worth getting one that maybe is
mid-range one that automatically selects
the voltage so you're not guessing or
you're not playing with it so on the
safe side I always go a little bit
higher just to make sure you know the
number is not really low sort of speak
fit was over here and you're seeing
zeros padded to the left of that that's
what's happening basically here right
it's 120 but the decimal point is here
so it's one two zero so this will be
point one two zero I guess it just feels
like it should not have to you know show
anything so that's not I would say that
this is a bad design bad design again
we're measuring voltage so I'll put them
in the voltage we're measuring AC solder
ranging so there's no threat of
accidentally not selecting the right one
I should just do a plug it right in I
try that again and get a davol tidge
from there 120 point one volts this one
shows a little bit of resolution it's
more expensive now I mentioned that you
know I wanted to show you how I would to
use a multimeter for and here's
something that I found out the other day
and this is something that we can
investigate together I haven't done this
yet
there's a switch on the wall that's over
that yonder that if I turn it off it
turns the power off on this here's the
interesting part though this right here
is a little light so I can see where I'm
going so I don't disturb my toe as often
and I have that switch off and yet this
is still partially on it's clearly a
wiring problem so I'm going to go and
shut off this and wise I've shut this
off you can see what this what the
reading becomes because I was very
surprised to see that and this is why
you would use a multimeter the switch is
off twenty five point six volt available
this switch is off and yet we're getting
some serious voltage obviously this
receptacle either needs to be replaced
there could be a grounding issue the
switch on the other side could have
grounding issues this can cause you know
issues not only with electronics in
general but also its safety
if fluke and other companies they make a
probe tester see if there's voltage and
all it does it lights up and goes misses
or beeps or blinks I have one myself if
I would have tested it on this outlet
right here it wouldn't have worked
because it's too low yet there you go
twenty five point six volts out readily
available so this is why you would use a
multimeter and this is why I always use
a multimeter to confirm that there's
nothing actually in here another option
available is the continuity test in a
diode current should only be flowing one
way if it flows the other way
we have problems the diode could be bad
for example what I really like about
this continuity test is that it makes
noise so it's like the own operation in
a sense but what it does is it
introduces voltage into the probes and
if that voltage reaches zero it makes a
beep so basically have an audible signal
rather than just having to read here and
here and here and here and here you
don't have time
to look at this each time you can just
sit there and listen actually why don't
we do that let's just probe the damn
thing all right so move it to a
continuity tester give it a quick test
good multimeters every single time you
touch it regardless of how long the
duration you should hear the beep these
cheaper multimeters a lot of times if
you go too fast it will act like as if
it didn't beep we'll give that test a
little later I want to see if this is
communicating with any other part of the
board I could okay so this means that
this point it is is connected all right
so this means that this diode has
somehow a direct connection on an
indirect connection but it's and that's
the advantage I can go and quickly probe
through a circuit board and test
continuity all right
continuity tester so let's do what I've
done with the other probe let's go
quickly through this and see if we can
you hear that
tolerance when it should be panned what
not should be perhaps it's too wide
right so it's not confidence
statistically speaking of course
and of course that's it's going to work
but if I went through and tested it real
quick may not catch it circuit analysis
probably not the best thing to do with
this little guy right here now
resistance as we spoke earlier basically
is the measure of how much voltage can
go through and it depends on the
properties of a resistor of the material
depends on the temperature sometimes the
pressure of whatever you're using in
this case we want to measure how much
current carrying ions that they're not
are in the water so here's what we're
going to do this is a fairly very easy
basic test now I put different problems
in here I'm just going to toss them
right in and turn this old reading to
where we can start getting some numbers
so 200 kilo ohm resistance that's when
it's currently at and it says 33 or 32
kilo ohm so 30 mm owns clear we're
getting different readings don't be
alarmed it all depends on quite a bit of
this depends on how far the distance
between the probes are where the ions
are this is just tap water so there's
going to be some ions floating around in
there which means it's somewhat
conductive now when we put this guy in
here salt what should we expect it to do
right watch what what should we expect
the resistance to be well I don't know
what the resistance is going to be but I
do know one thing I know that when we
add salt to water we're going to have
basically what's called an electrolyte
and so we basically have when we put
some of this in there is that sodium and
chlorine should disassociate should
break apart and as a result of that the
sodium which is conductive it's a metal
should didn't be able to basically be a
charge carrier and start allowing charge
to flow back and forth because can be
literally moving back and forth between
these probes as we do that we should
start noticing the resistance of these
guys going down now it's not predictable
how much down they're going to get it
doesn't matter all we're going to do is
just see if we can observe the
resistance going down a little salt
water or a little salt now it's not
necessarily going to be immediate I
probably should mix that a little bit
break the NaCl apart and it will start
carrying more current I'm just putting
more in right now to speed up the
process I'm a it's kind of cold in here
if I had hot water this would of course
be much much better we can see that the
fluke is now reading considerably less
now it's at three before was at eighteen
and it may have to move this craftsman
down a notch to give better resolution
there we go so it's not right about
three so now look at we're about getting
more consistent readings between the two
and that should make sense as I'm just
associating the sodium and the chloride
it means that this is becoming more
conductive as it becomes more conductive
we should see that the resistance should
reduce a little more here again I'm just
trying to speed up the process with a
little bit of work on my part you can
see that the resistance has dropped
initially this was showing 18 kilo homes
now it's around 1.6 this one was showing
30 kilo ohms now it's around 2.8 9 so
now I'm just going to have a little fun
now I'm going to be a little bad and I'm
just gonna pour a whole bunch in there
let's just have little extra fun dude
hmm
really just pour it on there that's nice
that's nice that is nice now if I wanted
now if my goal was to trying to see how
conductive I could get the easiest way
to do that is not to sit here and me to
do all the mechanical work of breaking
it apart it easiest way B to boil is if
I boil this who it'd be conductive quick
now I added a lot more salt in here you
can see the numbers are starting to
decrease again more rapidly most of the
salt as unfortunately is now collected
at the bottom it's really late and I
need to stay up because I want to finish
this video this is horrible
so um I'm gonna try a little salt water
maybe it's the cure-all maybe it'll just
make me stay awake and get this video
done right for you guys
probably gonna be pretty disgusting oh
good lord
mmm basic chemistry that reminds me
mmm if your glands are swollen this is
not a multimeter tip but if your glands
river swollen a little bit here gargle
saltwater when you're measuring light
bulbs and you want to check see if they
work you can really only do that with
these guys because they have a filament
that goes up zigzags its way across the
other end and connects back down so just
like a wire it has resistance and
continuity so you could for example
change it to the continuity
and keep one end on the outside and the
other firmly down
and you notice that it parently isn't
enough
for this continuity tester to go off so
we can move it to the resistance so it's
what's about 26 27 all all this is
telling us is that this light bulb still
works and I only mentioned this for
example if you're not sure whether you
should change the light bulb if you
change two or three of them and they are
none of them worked or you're just
curious whatever the reason is it's
another good reason to use the
multimeter for I'll try the continuity
tester on this first see if this one
goes off yeah sure enough it does so
it's saying 25 ohm so it within this
range it's saying hey coulier's
connection and that beep is going off
so I know that this light bulb works
depending on what you would use this
type of switch for this could be a kill
switch and oh switch red switch the
button that you used to launch a new
whatever but what if you didn't have the
schematics for this
maybe there's no writing or it was on
there and you couldn't see how this was
designed
my point is what if when I press down
which ones connect or disconnect how
would you know for certain let's say you
had to replace the switch with another
one and you had 10 minutes to do it and
you couldn't find the schematics you
have a multimeter but you don't have the
schematics does this close a circuit
does it open a circuit how would you
know well you could spend probably 10 15
minutes looking it up here they have
potentially a model number that may help
but more than a not more than not most
likely you'll have these switches and
you won't know exactly what the
connections are one of the ways that you
can do this is to simply just set it to
you can set it to own and you just start
probing from a common point and see so
let's keep it up
and let's test it out
so it's conductive there
not conductive they're not Cove there so
in other words
closed open open all right so now here's
the audible rather than just looking at
the resistance
closed
open open so that means that potentially
these two
when this Killswitch is active in
protecting potentially these could
disconnect and these two could connect I
don't know but this far what we know is
these two are connected these two are
not so now let's kill it
let's see if we can discover what just
occurred inside here
interesting my once closed is now
disconnected
no connection no connection
so thus far what I can be certain of is
that when this was open
these two
we're connected a closed circuit these
two were open circuit so what I'm going
to try now is to go down to this one
because I suspect that this is one set
and this is another set when it's open
as it is right now these two are
connecting these two are disconnecting
when it's closed
these two are disconnecting or an open
circuit this becomes a closed circuit or
it's connecting just what I'm assuming
and we can test that theory right now I
should hear an audible noise if now
these two are connected if my theory is
correct and indeed that's exactly what's
occurring and I should not hear any
noise on these two they should be
completely separate
so as expected so in very short order we
were able to basically find out the
internal schematics for this guy right
here I didn't need to look it up on
Google just simply by using the
continuity or the resistance reader you
could also use by the way on the
resistance meter does test switches to
see whether or not if you're using a a
rocker switch whether or not this good
connection maybe the switch is bad and
there's a high resistance when you press
a little bit when you press harder on it
then there's a less resistant all right
so on this particular multimeter it has
a nine volt and a 1.5 volt measurement
option and I'm really quite curious to
see if that's any fat readings going to
be any different than if I just go to my
DC and I measure it that way
I want basically what I'm trying to see
if there is a load if they put a like a
couple resistors in line and series just
to test whether because you can have a
high voltage battery that appears to be
high voltage but as soon as you pull
current from it as soon as you try and
load it with a load it fails and it
happens a lot with car batteries say 20
volts and again line this up and I'm
getting one point six 2 volts roughly
now I want to move it to the 1.50 and I
want to see if I get any different
reading on that so I'm getting a one
point five five five volt right to make
sure it's not me I'm going to switch it
back so there seems to be a little bit
of a difference barely so potentially it
could be putting a small load just to
get maybe a bit more of an accurate
reading so all of this basically means
that this batter should be good to go
for this next measurement I'm going to
measure current now a couple warnings
and please don't fast forward this part
especially if you're just not sure
of what I'm even referring to current is
what kills people not voltage if you
want proof of that think of the time in
winter when you're walking around and
you get shocked or you shock someone in
return that's twenty or thirty thousand
volts did you die current on the other
hand will kill and it only takes I'm not
mistaken something like one or two and
that depends on the body chemistry if
you're a lightweight if you drink salt
water like I just did if you went
exercising if it's a humid day or not
humid day all of those can drastically
affect how your body reacts to current
so be careful and if you're not sure
what you're doing then don't do it
because you don't want to get into an
accident you don't want to hurt yourself
or get yourself killed because you
didn't take appropriate steps to maybe
ask a professional ask someone who knows
what they're doing
another thing that I want to talk about
real quick is this in order to measure
current the multimeter isn't an
accessory or isn't seen as alien to the
circuit it is quite literally part of
the circuit this means that the
multimeter when it's connected will keep
the circuit going if you disconnect the
multimeter the circuit should no longer
work that's how you know you're
measuring current and that's why you
have to be so careful not only you have
to be careful not to touch the probes or
careful where you put the probes
especially if this in the close quarters
with high voltage or high current
components you also need to be careful
because this multimeter may not support
that rating this is ten amps but very
carefully if you utilize that point
earlier says only for thirty seconds max
and I wouldn't even go for that I have
no idea what the amperage rating on that
is the other thing is make sure your
probes are also compatible to measure
the amount of current and they should
they're certified the reading should say
so here it says cat three one thousand
volt but let me take a look on this
cable this cable says two thousand volts
eighteen American wire gauge can work up
to eighty degrees Celsius this one's
ready to cat three a thousand volt and
at ten amps so this is telling us again
and that and that should make sense
right it should make sense because if
the multimeter can take ten amps
certainly you would expect the probes
tool if it was any lower even
compatibility where this can measure
more but these won't all right let me
run through again what's happening I
have current traveling through that top
black probe this guy right here is
traveling through here it's going to
it's going to my multimeter which is
currently set at ten amps right now and
because we're measuring current I have
it in the gray one which I showed
earlier that must be connected when
you're measuring it ten amps and it's AC
ten amps so connect into the wall outlet
after that I've got it connected to the
red probe which is double clipped with
alligator clips to the main outlet then
it's going through the toaster it's
coming back out again into the black
connector finally it's returning home
through that screwdriver this is why you
don't give children screwdrivers because
you can very easily stick it into a wall
outlet ask my mom for details so I'm
going to turn it on notice not an issue
so far and what we're looking to do
again is we're looking to measure
current and keep in mind this is fairly
dangerous I do have live Kerner's
another lives so I have to be very
careful those two are close although
they're separated so just be cautious
here we go
there we go so right now it's measuring
six point seven three amps
so when someone has a toaster in the
microwave on it's very evident why a
fuse can go especially this older homes
have a 10 amp fuse you put a toaster on
you only have three point three amps
left before the fuse blows and you can
also notice that the resistance is
increasing because these coils are
getting hotter and hotter and hotter
inside this toast and as those coils get
hotter and hotter it increases
resistance all six and six and
three-quarters amps are going through
that multimeter this is why I encourage
you not to use these cheaper multimeters
because if an engineer in a different
country makes it
you can't verify whether the UL
certificate is justifiable whether when
they say up to a thousand volts or ten
amps whether that's really true or not
I've read many stories whether you
people have used these cheap amps and
they've run a test like this and thing
has blown or the probes have melted with
this much current coming through here
you know any of those situations can
occur so right now we're at six point
eight six amps my toast I can feel it oh
definitely getting heat through here all
that current that's making that toast
possible is going through that
multimeter and there we go we have
successfully measured current
hell of a lot better than saltwater
you