How to use a Multimeter for beginners: Part 3 - Resistance and Continuity

I'll you choose thanks again for joining me for this series on how to use a multimeter for beginners: in this series was actually the last part all this series for beginners because of this we gonna switch to a series when we come to pass and more advanced features a malt meters and how to make support vans measurements up but in this series part 3 we came to look at and constant UT and resistance and again will have some analogies explaining that but this get stuck into the response to the question I had to act in the last one which is basically that initially when power transmission all power generation first started I DC was initially employed and then they switch to pay see and what the reason was behind that and again thanks to everyone who you post Houston on so again it doesn't matter if you're our answer is way off and its was good just person on set and then learn from what other people have that post themselves now read probably two or three which I think economists correct are sort of with San say no San Gabriel and basically in his response he was saying that and it was a war currents and in the US Sen 1882 keep ties into the edison westinghouse and Tesla and then there was Steinmetz inside and out citizen was prominence planet to DC mostly for financial reasons as it once did DC laced panties to come you pictures BBQ to this and making lots of money Tesla advanced AC technology and westinghouse pushed the a/c system in opposition to you edison AC-one about 1891 say as I recall from watching some history programs I think they is austere daughter choosing that but there was a another on so that I kiosk that hours and looking for and and a user or a view record Beeb fan posted basically gave some maths about and other losses showing the losses thats occur in DC can this is AC current and I haven't actually gone unchecked is Matt's but it's basically EC if you trying to pass let's say it's %uh Mike 76 what's on AC you'd be you dealt to transmit about ATM DC but on AC you can do about 390 continuously and then probably the most correct on sir was and QB 15 and he said its easy to adjust the voltage or AC using transformers you want high voltage for long-distance transmissions to minimize power loss the lines heavy don't want those high voltages delivered to consumers it's a lot more difficult and expensive even these days said just voltage levels I'll DC and that is probably the most accurate cancer because in effect that is your problem you going to have this issue trying to transmit and electricity at the long long distances ya can have losses particularly voltage drop so you want to transmit acts at higher higher voltage and I know in in the a DC debt when they're using DC that basie hat hat loads of kinda booster stations along the way to get that PC at the right levels to consumers now SADC there's a problem with and transmitting high-voltage DC and then changing and then changing that voltage to you low voltage and if you transmit hi current with the with DC say that they too high voltage you then need really really fast conductors to you transmit thats that electricity whereas with AC you can transmit high-voltage far easy keep current life is so you're you're wise are far smaller and a course as said the transmission changing AC down to you low voltage and an Aussie checking out the current is far too easy a so that was around to that anyway let's get stuck in and have a look at continuity testing and resistance K so let's say I have a look at some and energies an act to try and get a better understanding of what on what we gonna make it today with a multimeter that being constant unity and resistance but again festival I need to thank contest again for the line 0 their click wonderful 74 the series I S is said its it's a nice and chill a multimeter in a few Grange which i think would suit a lot of people if you actually starting out and doing electronics electrical work but so let's get stuck in and have a closer look at this and hopefully I can get and gets a thus across with some reasonable understanding terms what we gonna be mission when we get to the multimeter site continuity if we go back to you hose pipe again and attack which is pushing water throughout hosepipe and water is pouring out the and continuity in essence just checked to see that we have a continuous part of from one day navarre conductor to another I K so if we happen to be cut this chopped this pipe over here and the water flow stopped coming outs at this end over here would have a problem and we want to try and find out where that break is and that's in essence what we do with our continuity tester on a multimeter is to check that we've got at a flow of electricity or if you like a flow water along a certain route or through a pipe between two points now this can be without again I say we are going to have a more advanced series we get a bit more down into your electronics and and how it all works but on a circuit that can be quite tricky and as a few things you need to remember here and these a a point in each member when we start using the multimeter for both continuity and resistance you should have your your secrets that you testing d energized meaning you shouldn't have power apply it to your sick it because it can be potentially dangerous an issue really know what you doing and or what have you do not have your circuit energized right so going back sconce newtie if you if this was a minute if this is a electrical circuit Sep 10 this is copper couple while on a circuit board and we got some point say we got a break over here and we've got some components over here and got a break yeah and we got to exit points over here if I had to take time my multimeter and and chip kahn snooty between II these two points over here and let me just label them save got point a be and see if I check between point ANP have we go to continue spar now it's fairly straightforward you can see we've got a break so this is a pipe we have water gushing out share we wouldn't have water coming out to point B where we want it and that to be a break in continuity and with a multimeter reported over here and it that the test which are mostly gonna demonstrate later we would not get out be so then we'd have to start troubleshooting and we take %uh multimeter and we would could take between another two points and so could have him check yes would have continuity over there rx take between these two points over here and we do last night we didn't and neck we could then start isolating and troubleshooting where outbreak Nasik it is now this can be quite complicated if we were an example na maging trying to check continuity between point a and see we would have continuity I can let's say we still had a break in a suit could have you here which we was a problem for us we needed flow across this component IVF pretending there's a component over here and is a component to be here icon snooty test in theory if the resistance was right would work and if we put up up leads Irish yeah weird we'd get a I the signal coming back to us and if you put our leads at this point down share and see we'd also continuity because we would have a part 3 here if we went down over here after this break and see we would still have continuity because we have a park flight flowing well flying straight up no here so in this case in a circuit like this you'd need to start removing components to help troubleshoot because you can have multiple pols I to you that the tests point and to troubleshoot that correctly you'd have to start removing components to try and eliminate points points have continuity say can find out where your break his now that's getting a little more advance but I just watched quickly highlighted that continuity testing can get quite tricky sometimes and you have to be very wary that if you doing it across the electrical an electronic or electrical circuit with multiple parts and components and you have to stop pulling things out to start isolating where your continuity break could be right so that sconce munity and I think I to you up before we get into resistance let's have a quick look at the mall to meet and see how we can do continue to check okay so you've got a multimeter it switched off at the moment and I said for this exercise we've got the fluke wonderful 7 and most multimeters do you have some sort so a continuity test although I'm some don't and then you may have to resort to using and the resistance test but tell you what will cover that offer me get to resistant I can use the resistance test all measurement part time I'll treat check continuity in essence it's the same thing except the continuity tester has a nice buzzer to let you know when you do you have continuity right side leets again the black one guys im sure common connector I can and then your 81 you'll have to look on your multimeter it normally guys into you the one with the voltage and the home some symbol i cant and that on the small to me too is that when I this year then we turned a multimeter on and reflected right round to this symbol over here and which is like i neva sound all almost like a SoundDock coming out of a speaker because that's where it is continuity now want to highlight I say the one handy feature on a flute which if you look at my multimeter reviews is something the Fuchs Arnone for and the way to first the one thing to do is always to check that your you you me trees working correctly hold you to it leads to get in touch make sure you get a good response said you don't start testing if you bat your something's wrong with your lead so we meet at you suddenly start getting the results you want but the flukes Jimmy have speaking have a latched continuity tester which is very quick and clear and that's if you if you are more serious issues over multimedia community Chris Cohan usefulness especially be checking small electrical electronic components size just something I want to highlight having a good conscientious test a certain and a lot of value right so we've got it day and basically as you can see the reason we getting that as which means we getting a complete blow from end to end between two points is because because test leads it's sending a test current and voltage through the wire to the multimeter to see that it's got a continuous flow between this point and through the multimeter and we put them together we get that beeping sound snow when it comes to safety as an as an example I've got the switch yet now i cant it could be there are 101 devices in bits and pieces that you can test for continuity could simply be a piece of wire and you don't know if there's a break in a piece of electrical cooled and you can and I said just remember what I said in the when I shiny the analogy always de-energized the circus that you want to test sconce community for but if you got that piece of electrical why he simply replace but private one end to the other probe the other and see whether you get up by as whether it's intermittent sometimes as bad as can be the worst problems you get something that works on of if you really are wire around you can then tell a spaceship got a good continuity tester with you gotta an intermittent fault for not but here we've got a switch and even on switches like this this which happens to be a doubles double pole double throw if I remember correctly sets got social connection parts inside online might not know which one of these connection tabs on the switch are connected when it's on so I'm actually just can't put let me just put the wants me to down there so the beauties we don't need to look at the display for this example we waiting to hear the sound so I put my one probe over there to see if his flow ok a connection between these two points nothing but put it today now be here nothing what I generally do you when I'm doing this because I always want to check that my multimeter is working in that might probes working I sometimes come back to %um i initial probe is I even touch might not directly touched the pro but I attach the same piece a wire the same piece of contact to make sure things are working right now I'm gonna flip the switch so when I flicked the switch that way one might logically think that these two points are here are connected sign I get my one probe tip and I get the other one I put them there nothing and not take them to these two cash finger so when the switches switch that way I now know that these two points are electrically connected this check that to you far points not connected these two not keys to our stress is a little example on how test a test to switch and Tess continuity and the switch and but of course testing continent she's got thousands abuses when trying to troubleshoot an electrical problems and is one of the most common uses the site itself measuring the voltage your continuity test is probably going to be one of the most most-used features on a multimeter for troubleshooting electrical or intimate mentioned electrical connection problems okay this go back to that piece of paper and have a look at resistance okay snipe him we back to I either a hosepipe or I'll out pipe which is has got water flying in it and you can imagine if we have a normal pipe I with water gushing out a bit I K and you get your hand and he squeeze it tight in the middle as i've represented here either squeeze it or you got a narrowing in the pipe what's gonna happen to you the blow the flow rate and the pressure of water coming out the other end budget pressure so that whole pressure that would be flying against you is going to drop and reduce and so will the floor right I K and and that means that basically so I talk about up for rates and volume we we talking about both your current in essence the amounts water which will come out here and the voltage is going to drop and that is in essence what resistance does on a piece of wire now getting kits it gets little more complicated when you got multiple pieces all I'm what-have-you but that's what no we we covering of a week or a single piece a while that single pot with water flying through it you have a restriction see the squeezed orange commission here got a piece of pipe and I got a plates in the middle weapon you got a small hole and and the cross-section that pipe what's gonna happen he said he had to slot that in you can sign you gonna get a reduction in that pressure and the flow rate and that in it in essence is what resistance is and Shia is a is a resistor and resistance NY basically do resistance is brought on by a the cross-section cross-sectional area all a conduct or material site could be cop could be steel could be silicon the topic material will have an effect on resistance and its cross-sectional area and as you can imagine you know this %uh the so that the cross section is like the size you're to pipe and then potentially the type of pipe that you've got war affects that live so you could have a I ATM pipe with very slippery signs in essence which kinda represents like material like copper or gold which allows watched flow very easily and you could have a pipe which let's this analogy is perhaps not the most active let's say we have a pipe with for all I'm fair or carpet inside it I K and it's a different kind of pot that may relate to I am hey a material like select and all or something like that which doesn't allow electricity to flow as easily or carbon for that matter it doesn't allow electricity player as easily says the cross-sectional let the cross-sectional area of material and and the top material so what happened so this is a a resistor which we our game to you measure right now but just against in without getting 2 in depth and and getting going into times law on on what happens with resistors in circuits when you have that that lost a resistor you lost now some your pressure and your playwright and if you remember back in science things just don't get lost energy doesn't get lost okay and its dissipated and what happens in there is a stroke this sort it dissipates the I am the those losses as heat you'll get heat coming off your sister so let's move on to the multimeter and see how I we measure that okay so let's get down to how we actually measure resistance with a multimeter axo again has we had before a black one is in the common connect on them on multimeter are 8-1 is on that Amiga sign who homes on the mall to meet which is normally shared with your book your voltage measurement and then we just flick our are selected through to the home all that Amiga sign again and the the mall to meet is set up to you am or to arrange I K and by default you'll see it's it's a in this overload might cause my skis got nothing to measure now then one interesting test is something tonight is at even your multimeter leads can have resistance which can affect your reading okay so watch continue is pretty sure probes together and just night as you can see there is even point 10 points to on I'm resistance in these leads nice as a couple things then this either potentially calibration on the or accuracy of your multimeter all that literally is the resistance in your leads now if you measuring something really critical you might meet action night that and on and on some multimeters you'll have a button that you can push a relative baton to cancel that out so to keep in essence 0 who and take a relatively reading way that at discounts that's that's reading on the screen but that's just something tonight okay so let's get to our switch so if we have it in that position like we did before and we'd put out two probes between those two points you can see we've got the over overload on screen name because it hasn't got any reading there's no continuity between those two points I should go to the east to because actually depending on where the switches could be either dashes and the bus which at this well. think when I checked his Nikon snooty there because I hear and there we go we've got that point to point for nasa remember basically Raza said there was a resistance potential in the lead sir in essence we've got and up close to you 0 resistance going through here I can satin as I play around you can see it's getting we getting a just about one I'm so this is also where you can check continuity if you don't have continuity buzzer is to put it to the resistance a setting on your multimeter and check resistance and you kinda what else is close to zero as possible to show that you've got good continuity right so now let's get to the resistor have this can be difficult my nephews prestech but so here we have our system what I'm gonna do first some gonna take the test in fact I'm gonna get some prospects that's gonna be just a little bit challenging without moving around fine take a measurement on the signed up that resistor on that wire we can see we've got basically almost zero times now to go to this other side across the resistor it is one killer I'm so one point 000 killer I'm so that is a thousand I'm its across that resistor let's get another resistor and again you might this is out circuit cuz if you're trying to measure find resistance in a circuit you you basically measuring the resistance between all the components between your two probes so if you want to measure something specifically sometimes you have to be very careful you have to take it out to the circuits to actually get a good keen reading are all she could have other components I within a circuit which could upset you reading but here we go we put the two probes on either side the resistor asked pushed down to make sure get a good tea and Erica 390 points 3 I'm now I can remember so this is a 390 I'm I resistor that point 2.3 at the end could be is that potentially the resistance which is sitting in your leads to save it something really critically measuring just remember you can have to account for even resistance in your annual lease itself and military its as straight forward as that spassky on the side and picking up the reading you can even see a measure the resistance of some interesting things like through my body so there we go I'm holding with his probe stocks in my hands and there's about one mega I'm I K and if yet to certain do it on on the same finger now that's interesting 2.3 make a.m. are thought it would have been this the other way around which can be some quite interesting things I'm just gonna quickie lick my finger very crisis but she Rica we take a reading and look at that having moisture on my hand is changing the resistance so the flow of electricity between those two points anyway there we get it's as simple as that and I hope you found this this whole series useful and interesting I will be starting up a the next series which is kinda the more advanced uses offer a multimeter and and advanced measurements Square will get into things like measuring current with current prime Group and shunt resistors and measuring consumption energy consumption like kinda thing say be keen to join for that or think someone else might be then certainly do share these videos or subscribe and again if you've gained any value Anna then pieced idk but give it a thumbs up and in the next series all fine and you said if quiz questions so that we can a post them in on Salam and hopefully they'll they'll give us a better understanding of electricity and electricity measurement thanks very much for watching

Channel: mjlorton

Views: 1,008,666

Rating: 4.8986626 out of 5

Keywords: mutimeters, for, dummies, novice, technician, auto, electrican, multi-meter, voltmeter, volt, meter, electrocution, electric, shock, electricity, electronics, resistance, ohms, continuity, silicone, test, leads, probes, polarity, Automobile

Id: InJhgwmj2So

Length: 27min 11sec (1631 seconds)

Published: Wed Feb 08 2012