How to use a multimeter like a pro, the ultimate guide

a multimeter at first could seem intimidating but by the end of this video you'll know everything you need to know to fully use your multimeter from what every sign means to what they do we'll also look at some examples and demonstrations on how each feature could be used finally we'll take a quick look at different multimeters and compare their features to decide which is best for you now every multimeter has different features but there are standard measurements and symbols across most units so let's take a look at that first first off we have voltage represented by a capital V this will allow you to measure voltage of power lines and devices the power in your home is alternating current also known as AC and is represented by a wave sign then we have DC current which is also known as direct current and this is represented by two lines one solid and the other dotted you'll usually have two voltage selectors on your meter one for alternating current and one for direct current the most devices that are intended to be plugged in or charged will have a label indicating their voltage and current type this battery for example outputs 18 volts direct current this jigsa for example has an input of 20 volts so let's use our multimeter and test this battery at the top of the battery we have labels which tells us which terminal is which after setting our multimeter to voltage direct current we then place our red wire on the positive and the black one on on the negative if the voltage is not matching the device requirements there's likely something wrong with your battery or your device in this case our range is pretty good and we have a good battery here now alternating current is what you'll usually find in the outlets of your house so before testing our Outlet proceed with Extreme Caution high voltage can cause death and serious injuries so to test this set your meter to voltage alternating current then place your probes in the socket when placing the probes the other could become instantly electrified so do not come in contact with the probes after placing them in the socket when testing deadly high voltage like this many recommend just using one hand as opposed to two by using two hands you're at risk of completing a circuit through your chest leaving you at greater risk of death from current passing through your body depending where you are in the world you'll read between 100 and 240 volts this multimeter shows us the results automatically by ranging by itself later in the video we'll talk about manual range ing multimeters which are these that have a bunch of numbers our next feature is ohms this is a measurement of resistance essentially how difficult it is for an electrical current to pass through a material if we place the probes on a copper wire for example we'll get a resistance of nearly zero this is because it's very easy for current to flow through the copper wire if we place the Probe on the rubber however we get o meaning open loop this is because little to no current can flow through the rubber which is why we use it to protect the from the wires and we use it to insulate wires in other words it's very difficult for electricity to pass through rubber we then have resistors these are devices that help us precisely regulate resistance to test these again it's quite simple we set our meter to ohms and place the probes on the leads this resistor for example is 21,600 ohms we'll talk about letter values later on in the video but this is 21.6 k k meaning Kila so this is 21,600 ohms an important thing to mention is that if you're testing a resistor on a circuit for example you can and will likely get a false reading this is because there's other paths with less resistance on the circuit that could give you a false reading leading you to believe that the resistor is damaged so you should always isolate what you're testing when possible the next common feature is continuity and this is one of the simplest and surprisingly useful features on a multimeter so this feature essentially just makes a tone when continuity is found with low enough resistance this feature can be used for example if we have a large row of wire like this and we want to verify that the wire inside is not broken anywhere now verifying that the wire inside is connected and functioning is virtually impossible without cutting it open except with a multimeter using the continuity we simply place our leads on each side of the wire if we get a tone we can verify that this wire is good it's unbroken and it's all good within this wire this feature is also helpful for finding wire positions let's say for example we want to know what pin this circuit goes to we place the Probe on the circuit and then with the other probe we touch each one of the pins to see which one it is we'll finally get a tone and now we know that this pin corresponds to this circuit these three features voltage ohms and continuity are the most common but we have a lot more things that multimeters can do next we have capacitance which is represented by this symbol capacitors are devices that store energy for later use in high demand applications to test these we set our meter to the option and in our case we have to press the selector button to switch to capacitance here at the top we get a capital f meaning farad which is what we need now before we test this capacitors are extremely dangerous exercise Extreme Caution these capacitors can be charged with high voltages that are very dangerous we have capacitors that are both polarized and non-polarized most capacitors should be labeled with their voltage and capacitance ratings by farads now usually farads are measured in micro scale so you'll usually have this symbol meaning micro this capacitor is reading 230 microfarads which is pretty standard it will usually have some tolerances we then have this one which is non-polarized at 7.5 microfarads with a 5% tolerance if we test it we get a reading Which is higher but it is within that 5% range moving on in our case on the same setting we have a diode symbol this is a diode and this device simply allows for current to pass in One Direction but not the other to test this we place our leads on the diode and get a reading if we reverse it however we should get no reading or open loop this diode is working properly as voltage can pass in One Direction but not the other if you get a reading in both directions or no reading in both directions then your diode is damaged our next feature is Herz or also known as frequency this is simply the speed of an electrical generator meaning the frequency of this alternating curve wave depending on where you are in the world you'll have somewhere between 50 and 60 HZ in your outlet and as usual whenever working with electricity exercise Extreme Caution so what we'll do is simply place our leads in the terminals of the outlet and we'll get 59.98 Herz now this is just barely off the 60 HZ standard of the United States many multimeters will also say Duty or have a percentage sign this is known as duty cycle and this tells us what percentage of the time there's positive current so when an alternating current is spinning you'll usually have 50% % on and 50% off in this case we have dead on 50% there's other applications where you have square waves that aren't on 50% of the time another common feature is the temperature probe this will either be represented by Celsius or Fahrenheit or a temperature symbol like this this one's pretty simple and straightforward it tells us either surface or ambient temperature meters with this feature will usually come with a separate probe that we have to connect to our meter and this should give us temperature this probe should not be wet another less common feature is HF this stands for hybrid parameter forward current gain common emitter it essentially measures transistors and in this case we have to use an adapter and place it on our input we then get our diode and have to figure out whether it's PNP or npn if we don't know what kind it is we look at the number and look for the data sheet on this transistor and it'll tell us which is the emitter base and collector we then align our transistor on the adapter and connect it to the board this should give us a current gain which we could verify again on the data sheet clearly this is a bit more of a specialized and complicated feature but it's good to know it's there here at the bottom we have amperage to test amperage we have two main options which is clamp and in series most meters will have a separate input for amperage testing this is often times because it's fused inside and has to take different paths also testing amperage in Series has its limitations from not exceeding 10 amps to not doing it for longer than 10 20 seconds if you exceed the limit of your meter a fuse inside will pop and you'll need to replace it by disassembling the unit and changing the fuse so to test amperage like this you'll have to break the connection of the device and reconnect it with your probes so I'm going to show you by connecting this in series with my power line to this charger now exercise Extreme Caution and do not repeat this demonstration without a thorough understanding and the necessary safety precautions so we'll change our probe to the amperage setting we'll connect the wires and complete the loop with the meter and our meter will display how many amps are being drawn by the device and that's how you test amps but a much safer way to test amps is with the clamp option to test with the clamp you must isolate one of the wires if you put both wires in the clamp the charges will cancel themselves out and give you no results to demonstrate this we'll use our welder which allows us to PL the clamps on the anode or in other words the positive wire we could set our amperage on the device and see if what we're getting is the correct amount so we'll simply set our meter to amps and put the clamp on the PO positive wire and that's how we get amperage readings from the clamp and of course this is a much simpler safer way to read amperage another feature common on these clamp devices is ncv which is no contact voltage this is a setting that the device will alert you when you approach voltage with the tip of the device this is just an extra safety feature for finding live wires I wouldn't usually rely on this feature and those are the most common features on a multimeter but there's a few more things we have to learn to fully understand everything on on a meter another important thing to learn is measurement units those measurement units are capital M which is million capital K which is kilo which is 1,000 lowercase M which is Millie which is 1 1,000 and this symbol which is micro which is 1 one millionth rarely you'll also see a lowercase n meaning Nano which is 1 one billionth we've created a multimeter cheat sheet which we're giving away for free this cheat sheet has all the essential information on learning how to use your me met and it's a quick reference for the values and what each feature does you can download this for free in the description below so by understanding these measurement units we can Now understand a lot more things on our meter for example this is a manual ranging meter a meter with no numbers is auto ranging and will automatically switch between values though these meters still allow you to manually select the range with this button but then we have other meters that don't have Auto ranging with meters like this you have to select the correct range to get a result and as we could see we have a lot of our units here M for million k for kilo the symbol for micro the lowercase M for Millie and so on now this may seem a bit complicated but selecting the correct range is not difficult so let's use our multimeter and test this battery to test it we simply set the value at the highest range we then turn the dial down until we get a reading if we get a one we've gone too far and we need to go to a higher range and that's it it's as simple as that so now you pretty much know everything but besides this there's a few more more quirks and features of multimeters you should know for example on many meters you have a Max minimum and average option when this feature is activated you simply get displayed the stored maximum or minimum or average voltage reached since activating the feature the hold button pretty simple it just stops the display where it is allowing you to hold values for reference if needed besides this most meters also have a light which can be turned on and off and a final thing to mention is never to exceed the voltage ratings on your device device now this is unlikely as most ratings go up to 500 volts and it's rare that you'll ever work with anything more than that but it's important to ensure and know the limits of your meter anyway and finally how do you select a multimeter to buy the first thing to consider is what features are you going to need that were mentioned another aspect is whether the meter is true RMS this means root means Square now some currents can often have waves that distort the readings and cause up to a 40% error rate when reading however meters that have true RMS correct for this so that's an important aspect to consider the next thing to consider is whether your meter has Auto ranging this feature greatly increases the ease of use though really it's not necessary and if you're just going to occasionally use a meter then maybe it's okay to go with a less expensive manual ranging meter now in the description below I've linked multiple options from quality to budget so if you're interested in buying you can check it out there

Channel: James Gatlin

Views: 642,067

Keywords: how to use a multimeter, how to test diode, how to use a meter, how to test elecricity, multimeter, how to test voltage, how to test amperage, how to use ohms, ohms

Id: 0loXukB302Q

Length: 12min 55sec (775 seconds)

Published: Sun Jan 21 2024