Everything Electrical:How to Use The Functions On Your Multi-meter

Preface: Have you ever studied electricity in a college class or trade school and still felt puzzled atthe end leaving you feeling like the teacher failed you or that the theory just didn’t give you anythinguseful to use on the field. That they didn’t prepare you for those uncommon or intermittent electricalissues that leave you feeling that you don’t have a plan of attack. Well either way great, you’re notalone. I myself read about 10 full textbooks on electrical, electronics, industrial electrical andautomotive electricity, that by the way were not cheap averaging in cost around 150$ each. But thesebooks still left me feeling they failed in many aspects to teach you real world tricks and tips. Well Iwrite this book to educate in a simpler way, for everyone to understand beginners and veterantechnicians alike. There is no reason to complicate things with big words that usually are leftunexplained by other books and to make it even harder to understand with bad examples. This book ispriced low but because I feel that everyone should know at least the basics. I will also include manyexamples of each topic for better understanding. I recommend you reading the book front to back evenif you feel you’ve read too much theory of electricity already. My goal is to make you “the electricalguy” that will fearlessly tackle any job. If this book does not teach you everything you wanted toknow, I guarantee that it will at least be a very powerful supplement to your learning on electricaltesting. I hope you enjoy.

My Own Take On Electricity Everyone should know that anything that is technical, including electricity, involves a lot ofcomplicated physics and if I wanted to I can talk about how things happen down to the atom level. Butfor the sake of understanding, keeping it as simple as I can and to teach only what you need to and getto working on electrical problems as soon as possible, just accept that the way I’m explaining it isjust for ease. Otherwise this book would be way too long and you would NOT want to read it all. Butmy methods and examples do teach and WILL work in the real world for real life electrical issues.

His book will be part of a series on how to use multi-meters as there is a lot of material to cover andI plan to cover everything about the using of your meter to measure electricity.

Table Of Contents

Ch. 1: Introduction To Multi-meters: Manual, Auto Ranging and Analog

Ch.2: Voltage DC & AC

Ch.3: Resistance, Continuity, Diode and Capacitance Function

Ch.4: Amperage DC & AC

Ch.5: Hz & Duty Cycle

Ch.6: Temperature

Conclusion: (Summary & Ending Words)

Ch. 1: Introduction To Multi-meters: Manual, Auto Ranging andAnalog

A multi-meter is an electrical testing tool that combines many different kinds of electrical meters intoone. The different symbols on the multi-meter represents a meter setting that measures somethingcompletely different from other settings. The placement of the dial indicates what meter setting youare on. There are three very different multi-meters I will introduce. The Analog multi-meter, theManual multi-meter and the Auto-Ranging multi-meter. The way you actually test something witheither of these multi-meters is actually the same, the difference is in the setup before testing.

Let’s go ahead and look at the face of each multi-meters to see what they look like and note all theimportant factors about each of them.

Analog:

The Analog multi-meter was the first multi-meter to come out many decades ago. In this multi-meter,the unit AND the unit ranges must be manually selected via the dial.

(To use this meter you have to move the dial to the unit you want to measure as well as the exact rangeyou expect to measure in. As an example I will define the units on this meter and the ranges for eachof the units. In this multi-meter, the measurement display is shown as a moving needle through anumber wheel placed in the back of the needle. )

(As you can see around the dial, there are many unit settings to choose from. One thing to note on thismeter is the color of the setting. For example, the yellow capital “V” with the two straight lines is aunit called direct volts or DC volts and has many different ranges under it. It include the 2.5 volt, 10volt, 50 volt, 200 volt and 500 volt ranges. All these ranges belong under one unit of measure, the DCvolt. Another example is the blue unit “mA” or milliamps. This unit has dial ranges that include the5mA, 50mA, 500mA, etc. All these ranges belong under one unit of measure the milliamp. )

Ranges are best defines as the maximum number value you can measure of that unit setting you are on.In the 10 volt range setting the meter will only measure up to 10 volts. The analog multi-meterrequires you to know more or less how much you expect to measure of the unit before you willmeasure, so that you choose the best ranges to measure in.

Tip: If you own one of these meters or a similar meter that requires you to manually select ranges, thebest way to use these and not have to worry so much about what ranges to choose is to start at thehighest setting. If when measuring, the number measured on the needle display is too small you shouldmove down one range, for a better resolution.

(This is the measurement display. After you have chosen your unit and range, next is to pay attentionto only the number values that match your unit selected.)

Manual Ranging:

The Manual Ranging multi-meter is a lot like the analog meter. In this multi-meter, everything is alsomanually selected via the dial and depending on your setting the maximum allowable measure is alsoindicated. For Example: If you are on the 200v setting, you are only allowed to measure up to 200v.Any measurement above 200v cannot be read and will be displayed over the limit. To correct this,you must select a range setting higher than the reading you expect or just continue to move the dial to ahigher setting until a solid measurement is seen.

In this multi-meter, the measurement display is a digital number screen.

(In this picture you see an example of a Manual Ranging multi-meter. The setting and specific range isselected through the dial. The measurements on this meter is displayed through a digital numberscreen. )

(As you can see around the dial, there are many unit settings to choose from. For example, the capital“V” with the two straight lines is a unit called direct volts or DC volts and has many different rangesunder it. It includes the 200 millivolt, 2000 millivolt, 20 volt, 200 volt and 500 volt ranges. All theseranges belong under one unit of measure, the DC volt. Another example is the unit “A” with the twostraight lines. This unit has dial ranges that include the 200uA, 2000uA, 20mA and 200mA. All theseranges belong under one unit of measure the “amp”. )

Ranges are best defines as the maximum number value you can measure of that unit setting you are on.In the 20mA range setting the meter will only measure up to 20mA. The Manual ranging multi-meterrequires you to know more or less how much you expect to measure of the unit before you willmeasure, so that you choose the best ranges to measure in.

Tip: If you own one of these meters or a similar meter that requires you to manually select ranges, thebest way to use these and not have to worry so much about what ranges to choose is to start at thehighest setting. If when measuring, the number measured on the display is too small you should movedown one range, for a better resolution.

Auto Ranging:

The Auto Ranging multi-meter is a lot easier to use than both the other meters. In this multi-meter,everything is simplified and the ranges for a unit of measurement is automatically adjusted by themeter itself. All you have to do is select your unit to measure via the dial and depending on yoursetting the meter will automatically take care of any range issues. For Example: If you are on the DCVolt setting regardless of whether what you measured read volt or millivolts, the meter willautomatically adjust for the reading that it took and display in the best range. There is no need toselect a range setting higher than the reading you expect, this is done automatically for you so you canfocus more on taking the actual measurement.

In this multi-meter, the measurement display is a digital number screen.

(In this picture you see an example of an Auto Ranging multi-meter. The settings are selected throughthe dial and the range for each setting is automatically adjusted by the meter itself.)

Once you have your meter set to the desired setting, the test probe leads can used for measuring thatspecific electrical unit.

The most common units, their symbols and their measurement meanings are as follows..

(This chart shows all the different common symbols or abbreviations you will see on a multi-meter.There may be other extra symbols on your meter that I may have not included, but the ones I includeare the only ones you will actually ever use professionally. Keep these definitions in mind and handywhen selecting your measurement setting with the dial on your meter.)

Depending on what you will be measuring, you turn the dial to the desired setting.

The next thing to note about any multi-meter is the test probes. Include with the meter will come a setof test probes. One black test probe, one red colored test probe.

(These are your test probe that will also come along with your multi-meter. The black probe willalways be installed in the COM or common socket, regardless of what dial setting you are on. Thered probe on the other hand, will have to be moved around to a different socket depending on whatdial setting you are on. The red probe is installed in the socket that matches the symbol you selectedwith the dial settings on your meter. For example, if the dial is on an Amperage setting, you willinstall the red probe into the socket that has the same Amperage symbol as the one on the dial settingyou selected.)

Here are some images to illustrate what I mean..

(Here we see the DC volt setting selected on the dial. The red probe must be installed in the metersocket that is labeled for Volts.)

(Here we see the AC amp setting selected on the dial. The red probe must be installed in the metersocket that is labeled with the symbol for “amps”. The black probe always goes to the COM socket.)

Now let’s go ahead and explore the auto ranging multi-meters with different functioned buttons….

The Dial and The Settings: The dial in the center of the multi-meter is used to switch to the desiredmeasurement setting. As explained before, you should already know what the symbols mean and knowwhat you are trying to measure. Then you follow with turning the dial to the symbol that representsyour desired measurement setting.

The Probe Sockets: The red and black socket near the bottom of the multi-meter are where you willinstall your black and red test probes. The black probe always goes to the COM socket and the redprobe is installed in the socket that matches the symbol you have selected on the dial.

The Buttons and Purposes:

Range: The RANGE button is used when you are in a setting that can measure the unit selected inmore than one ranges of measurement. Milliamps (mA), Microamps (uA) and Amps (A) are the sameunit, they are all a measure of amperages or Amps. The only different is amount of the measured unit.Milli means “one thousandth” of something. Micro means one millionth of something. This means1,000mA= 1A and 1,000,000=1A also. Its just a different way of reading something becausesometimes in electricity, you will read very tiny values. Like one dozen eggs or 12 eggs is the samething just measured differently. The fact is sometimes you really will have to measure in milli units ormicro units because the readings you take from something electronic will actually be that tiny!

Example: If you wanted to measure something in millivolts(mV) but had a measurement displaying involts(V), you push the RANGE button until it displays the reading in millivolts(mV). It is the sameexact reading only it is displaying it in a different way by a different amount.

Select: The SELECT is used when you are in a dial setting that has more than one function. ForExample: If you were in the dial setting that contained the diode, capacitance, continuity andresistance test all in one setting, you would use this button to switch between them into the one youdesired.

*C/*F: This button simply changes between measuring in Celsius (*C) or Fahrenheit (*F) when thedial is on the Temperature setting.

Hold: The HOLD button is used to hold or “lock” an already taken measurement onto the screen of themulti-meter. Removing the probes from the test area or test piece will not affect the held reading. Toreset back to normal and start a new measurement, push the hold button again.

Hz/Duty: This button simply changes between measuring in Frequency (Hz) or Duty Cycle (Duty)when the dial is on the Hz/Duty setting. I will explain all these in depth later once we get to testing.

The Display: The screen display on top will show your measurement, along with an icon thatrepresents the range and/or function setting you are currently on.

Now you are ready for starting a measurement. Remember that with any multimeter, First select theunit of measurement through the dial and Second install the black probe to the COM and the red probeto the socket that matches your selected dial setting on the meter. If you do not have an auto rangingmulti-meter, just manually choose a range setting higher than you expect to measure. For this book Iwill teach you how to use the digital auto-ranging multi-meter simply because it is more widelycommon and used and is easier to use. Just keep in mind that the knowledge of how to set up themeters and the differences explained between the kinds of multi-meters will also allow you tounderstand how to use the other kinds of multi-meters if you own one already.

Ch.2: Voltage AC and DCImportant terms to remember before voltage testing..

Voltage Measurements: Any voltage measurement is a measure of the amount of electrical pressure(voltage) that is pushing the electricity through an electric circuit. Just like how a water circuit in yourhouse needs pressure from the water company’s water pump to flow the water all the way to yourhouse. Each electrical circuit will have a specific voltage to it for it to work. The voltage for thecircuit will be depending on the voltage that the power source, for this circuit, provides. It is the jobof the meter in the volt setting (voltmeter) to measure and confirm that this voltage from the powersource is present at the electrical device it is powering. It is also used to confirm voltage (electricalpressure) at parts of a circuit where it should be present.

Power Sources: A power source includes batteries, generators, solar panels, etc. There are two mainpower sources to know about when determining what of the two volt setting to use on the dial of yourmeter. An AC power source, such as from an AC generator, produces a very different kind ofelectrical pressure (voltage) than a DC power source, such as from a battery.

The AC voltage setting on your meter will be used when measuring voltages from circuits poweredby an AC power source. This includes household power outlets, household wiring, Industrial wiringor practically any other electric circuit powered by a generator.

Example: A 110 volt AC circuit requires it have a 110 volt AC power source such as a 110 voltgenerator. This voltage can be observed and measured with your AC voltmeter across the electricaldevice for the circuit.

(This illustration shows a 110 volt AC circuit and the AC voltmeter selected for use. The test probesmust touch the metal inside the wires or the metal at the light’s terminals, if available, in order to get avolt reading. Touching the insulation of the wire is not enough. In the image you can see the probes ofour AC voltmeter are touching inside the wire. You also have to have the circuit on to see whatvoltage is available at the light.)

Note: If you didn’t know what I meant by electrical circuit, let me explain. An electrical circuit is aset of electrical parts that when put together can make something useful, such as light. Every electrical

circuit needs a power source, a power feed and a return wire, a switch for control of the circuit andthe electrical device you want to power. The previous image I have shown is a basic AC circuitinvolving the power source(generator), the two power and return wires, a switch and a light bulb.

The DC voltage setting will be used when measuring voltages from circuits powered by a DC powersource. This includes many automotive, motorcycle, aviation, some industrial electric circuits orpractically any other circuit that is powered through a battery or a solar panel.

Example 1: A 12 volt DC circuit requires it have a 12 volt DC power source such as a 12 voltbattery. This voltage can be observed and measured with your DC voltmeter across the electricaldevice for the circuit.

(This illustration shows a 12 volt DC circuit and the DC voltmeter selected for use. The test probesmust touch the metal in the wires or the metal at the light’s terminals, if available, in order to get avolt reading. In the image you see the probes of the DC voltmeter are touching inside the wire. Youalso have to have the circuit on to see what voltage is available at the light.)

In either of these settings you are dealing with measuring voltages or the electrical pressure thatmakes the electricity flow. Every circuit needs voltage to make the electricity flow, just like how thewater in water pipes need pressure from a water pump to make it flow. You can test for voltage at theelectrical device to confirm that the voltage that makes the electricity flow is available at the light.Whether it is ac or dc voltage, the hook up to a test area for measurement of volts is the same.

Note: When testing using your multi-meter, any measurements in any setting should be recorded andanalyzed or compared to good values to see if they are within proper specs.

Reminder and Helping Tips: When using a volt setting, the test probes must be touching the metal partof the wires or terminals of the electrical device to get a reading. There are add on tools for yourmulti-meter that make this job easier. They are called wire piercing probes.

(This illustration shows different examples to connect your voltmeter probes to a wire for a voltagemeasurement. You must make contact with the metal inside the wire to get a volt reading. The topimage shows the tip of a test probe, piercing the wire to make contact and the other two images showtwo different kinds of add on tools (wire piercing probes) for your test probes that make this jobeasier and don’t require you to hold the probe in place to secure a good contact and measurement.Just be sure that once you are done testing, you put a bit of electricians tape to cover the hole you mayhave made during testing)

One other basic thing you can use your voltmeter for is to check the voltage (electrical pressure) apower source may have. One example is checking the voltage that a battery you may have lyingaround still has. A battery usually has a voltage rating on it, that you can compare your readings to. Ifthe battery is well below even half a volt of the rating that it should have, it is done for.

Note: Many batteries, when they are below proper voltage, can be recharged with a charger to restorethe voltage to the battery.

(Testing our battery in our circuit to check what pressure or voltage it is providing our circuit.)

(Testing various battery voltages. Here I want you to get the idea of how you would measure batteryvoltages.)

Note: In the previous picture, I want you to also note that the voltmeter in the 120v battery is readinga negative voltage. This is because the test probes are reversed. No damage will be done to yourmeter if you reversed the test probes in the volt settings, you will simply get a negative sign on yourreading.

For a very detailed training of how to use your voltmeter like a pro and test any electrical problemfast, check out my other book coming very soon “Everything Electrical: How To Test Circuits Like APro: Part 1”.

Ch.3: Resistance, Continuity, Diode and Capacitance functionImportant terms to remember before testing..

Resistance: Everything electrical has some degree of resistance. Resistance refers to the resistanceto electricity. Anything that disrupts, slows or prevents the flow of electricity is electrical resistance.Wires, Connectors, Switches, Terminals, etc. all have resistance. These things when “good” have avery tiny resistance that usually doesn’t interfere at all with the circuit working properly. But whenthey are bad, they can have too much resistance and it causes problems to the circuit. The mainresistance of any circuit should always be the electrical load of the circuit (electrical device, thiscase our light bulb in the circuit). It is the job of the resistance test (ohmmeter) to measure resistance.The unit for resistance you will see next to your reading on your ohmmeter is called the ohm.

Continuity: The word continuity refers to completeness of a circuit. If there are no broken wires orconnectors, bad light or anything, the circuit is said to be continuous. A continuity test tests forcontinuity of something electrical between the two test probes. When there is continuity you will heara continuous beep.

Diode: A diode is an electrical device that allows electricity to flow only one way. It’s like anelectrical check valve. Diodes are usually only used in AC circuits where electricity goes back andforth. This is why AC is called alternating. Because electricity alternates flowing back and forth inboth directions. The diode when bad does not control the electricity to flow one way anymore. Thiswill case problems to how the circuit works. A Diode test tests for the proper working of any diodes.

Capacitance: Capacitance refers to the capacity of a capacitor. A capacitor is an electrical devicethat is able to store electricity, somewhat similar to a battery. The capacitance test measures thecapacity of electrical storage a capacitor can take.

In this meter dial setting you are dealing with measuring Resistance, Continuity, Diodes andCapacitance. These settings are usually grouped into one because in every one of them, the multi-meter is actually sending out its own electricity to complete these kinds of tests. Regardless of thespecific setting, the hook up to a test piece for measurement is nearly the same.

Note: When testing using your multi-meter, any measurements in any setting should be recorded andanalyzed or compared to good values to see if they are within proper specs.

Testing Any Component Using The Ohmmeter:

(This illustration shows the multi-meter set to the Resistance or Ohm setting. We see how to test awire for resistance. The same rules, like the voltmeter, apply about needing to touch the inside of thewire to get a reading. In this setting you are testing for resistance in ohms between where you placethe two test probes. If there is resistance between the two test probes through the wire, the meter willdisplay the amount in ohms. If there is absolutely no resistance at all you will read 0 ohms. But ifthere is unlimited or way too much resistance between the two test probes, the ohmmeter will notread anything and instead display an OL or infinite symbol which indicates a break somewhere in thewire even if the break is not visible.)

(This illustration shows multiple multi-meters set to the ohmmeter setting. We see how to test variousthings for resistance. Before testing anything for resistance, it must first be removed from the circuitand tested without being connected to anything but the meter. When the tester is installed across thetwo terminals of an electrical part, the reading of amount of resistance will be displayed in ohms. Thereadings shown above are just for examples, they are not readings you will always get.)

Note: When testing using your ohmmeter, any measurements in any setting should be recorded andanalyzed or compared to good values to see if they are within proper specs.

Reminder: Before testing anything for resistance, it must first be removed from the circuit and testedwithout being connected to anything but the meter. Or tested with the circuit “OFF”.

Testing For Continuity:

(This illustration shows the multi-meter set to the continuity setting. We see how to test a wire forcontinuity. The same rules, like the voltmeter, apply about needing to touch the inside of the wire toget a reading. In this setting you are testing for continuity between where you place the two testprobes. If there is continuity between the two test probes through the wire, the continuity tester willbeep. If there is no continuity between the two test probes the tester will not beep and it indicates abreak somewhere in the wire even if the break is not visible.)

(This illustration shows multiple multi-meters set to the continuity setting. We see how to test variousthings for continuity. When the tester beeps, this indicates good continuity. If it does not beep, thisindicates that there is a break somewhere in the part being tested even if the break is not visible.)

You can see that the continuity tester and the ohmmeter are very similar. Actually, they ARE the sametester and many times the continuity tester will also give you an ohm reading. The difference is simply

the beeping that indicates continuity.

Reminder: Before testing anything for continuity, it must first be removed from the circuit and testedwithout being connected to anything but the meter. Or tested with the circuit “OFF”.

Testing Diodes:Before we test a diode let’s take a look at what it actually looks like..

(In this picture you see a typical looking diode. The band on the diode marks the direction ofelectrical flow when it is installed. Remember that the diode is like a one way check valve, it onlyallows electricity to flow one way when it is installed to a circuit. This is only important to notebecause the Diode Test has two steps to it.)

Set your multi-meter to the diode function and take a look at how to test a diode in two steps..

(Step One: With your multi-meter already set to diode test, touch one probe to each of the twoterminals coming out of the diode. Note the reading you get and continue to step 2.)

(Step Two: Now that you have tested the diode one way, reverse the position of the test probes andretest it the reversed way now.)

Results: With the diode test you should get a “no reading” one way and a number reading the otherway. If the diode is good you will see these results. If not, then the diode is bad.

Testing Capacitance in Capacitors:Before we test a capacitor let’s take a look at what it actually might look like..

(This illustration shows different variations of what some capacitors may look like. The first one is acapacitor that must be installed a very specific way into a circuit. The short leg to the negative wireof the circuit. This is known as an Electrolytic Capacitor. The other capacitors can be installed andalso tested either way. We will use the first one for testing because it seems to be the most common.)

Note: All capacitors are labeled in a unit called Farads. When testing for capacitance, you willexpect to get a farad(f), milli farad(mf), micro farad(uf) and even a pico farad(pf) reading on themulti-meter screen.

(To test a capacitor for it’s capacitance, set the meter to the symbol for capacitance. Touch the testprobes to each of the legs of the capacitor. You should get a reading in the unit farads that matcheswhat the capacitor has written on it’s case.)

Note: The Capacitance test on the multi-meter is usually only accurate to small capacitors. It loses itsaccuracy on bigger capacitors. To test any capacitor accurately, an actual capacitance meter shouldbe used on bigger capacitors.

Ch.4: Amperage DC, AC and Milliamps.In these settings you are dealing with measuring amperages or amps. Whether it is ac or dc amperageor ranging from 1000amps to a few milliamps, the hook up to a test area for measurement is the same.

What is amperage? Amperage is the amount of actual electricity flowing through an electric circuit. Itcan be compared to the amount of water flowing through a water circuit. Do not mix voltage withamperage. Remember voltage is electrical pressure, amperage is the actual amount of electricityflowing through the circuit because of that electrical pressure. Amperage can also be called current,current flow, amps and even electrical flow. Now let’s see how we would measure this using ourmulti-meter..

Note: When testing using your multi-meter, any measurements in any setting should be recorded andanalyzed or compared to good values to see if they are within proper specs.

Testing For Amperage

Before we can test for amperage or “amps”, we must take a look at how testing using the ampmeterdiffers from all the rest of the tests on the multi-meter. First, you break the circuit you are testing,either in a connector or somewhere that is easily accessible. Anywhere is fine actually but you wantto choose a place on the circuit that is easy to break and reconnect the circuit in. Second, you installthe ampmeter in between the break you created. This will allow electricity to flow through theampmeter to measure exactly how much is flowing through.

(This illustration shows how the ampmeter is installed for testing. There are two steps. First, youmust break the circuit. Second you install the ampmeter in between the break. Turn on the circuit andcheck your reading. You are actually completing the circuit through the ampmeter when you are doingthis.)

(DC Amps: In this picture we see our original circuit with an ampmeter installed. The dial setting onthe multi-meter is set to DC amps and the meter has been placed in between the circuit. We see thatwith the circuit on, we get a reading in the unit amps of how much electricity is flowing.)

(AC Amps: In this picture we see our original circuit with an ampmeter installed. The dial setting onthe multi-meter is set to AC amps now and the meter has been placed in between the circuit. We seethat with the circuit on, we get a reading in the unit amps of how much electricity is flowing.)

As you can see, testing for AC amps or DC amps using a multi-meter is the same. You first break thecircuit, then you install the meter in between the break.

Important Note: The only thing you must worry about when using your ampmeter is the possibility ofcausing an accidental short with it. Take care when using it as the ampmeter completes the circuit.You can think of the ampmeter as if it were two jumper wire with a measuring gauge on it. NEVERplace an ampmeter across an electrical device when the device is installed in a live circuit or acrossany battery either. YOU WILL CAUSE A SHORT. Worst of all, you will probably destroy your meterif you cause a short with it. Be careful.

For the sake of understanding the symbols on your meter, I will add one more example where a circuitread milliamps instead of amps. Just remember milliamps is not a new unit, it is still under amps.Milliamps is simply just a fraction of what an amp is in value.

(In this circuit we are connected for reading amps just as usual. If you have a manual ranging multi-meter this is where you would select the mA setting on the dial. If you have an auto ranging multi-meter it will adjust the range automatically. You see here that with a tiny battery and a tiny light youalso got a tiny amperage. 10 milliamps to be exact.)

For advanced training on amperage testing using other kinds of meters take some time to look at myother book coming very soon “Everything Electrical: How To Test Circuits Like a Pro. Part 2”

Ch.5: Hz & Duty CycleImportant terms to remember:

Frequency: Frequency can be best explained as a measurement of how frequent (per second)electricity changes in a circuit. Up until this point you have only seen a circuit just be either “on” or“off”. However, in many of today’s circuits involving electronic, the electricity is switched on and offvery fast. The idea behind this is that with switching something electrical on and off very fast you areable to still power the device the same as if it were always on but also save some electricity fromwhen it is in the off part of the switching. The switching of electricity is normally done very fast. Theunit for measuring frequency of a circuit is hertz(Hz).The most common frequency I can think of isthe 60hz from your household power outlets. The 60hz means the electricity in the circuit is beingswitched on and off 60 times per second!

Hertz: The unit for measuring frequency in a circuit. This is a measure of how many times per secondthe voltage level changes (frequency).

Example 1: If a circuit has a frequency of 2000hz, this means that the voltage level changes from highto low 2,000 times!

Example 2: If a circuit has a frequency of 200khz, this means that the voltage level changes from highto low 200,000 times! Pay attention to the K before HZ in this example. The K means thousand.

(This example is a graphical view of what is actually happening to the voltage levels when referringto frequency. As you see here, the voltage switches from high voltage to low voltage. The amount oftimes it switches high to low per one second is the frequency. Here there are three high to lowswitching per second so that equates 3HZ.)

(Another example of frequency. The amount of times per second the electricity switches from high tolow. In this example the frequency is 5hz.)

Cycle:

One complete high and low is known as a cycle. When textbooks refer to frequency they usually say20 cycles per second when talking about 20HZ. A cycle is the time it takes to complete one transitionto high voltage and one transition to low voltage, starting at the beginning of the high portion all theway to the end of the low portion.

(This is a picture example of a cycle. In talking about frequency many usually refer to a frequency as acertain amount of cycles per second. A cycle is a complete transition from the beginning of a highvoltage all the way to the end of the low portion.)

Duty Cycle: The duty cycle is related to the talk about frequency. Duty cycle is a percentage readingmade from the amount of “on time” as compared to “off time”. To find this measurement manually you

can take one cycle from the frequency and compare the High (ON) portion to the Low (OFF) portion.This can only be performed using an oscilloscope. I will give more about this in my next book“Everything Electrical: How To Use Any Oscilloscope”

Frequency and duty cycle are often confuse to be the same. They are not the same. Rememberfrequency is how frequent per second the electricity is changing. Duty cycle is a percentage of the ontime compared to the off time of this switching.

(Example of Duty Cycle: The percentage of on time, compared to off time of the switching. Thelonger the ON time compared to the OFF time, the higher the duty cycle percentage displayed on yourmulti-meter. In this illustration there are three examples of duty cycles and what they actually looklike when graphed.)

Measuring Frequency Or Duty Cycle:Now I must admit these dial settings may or may not ever be useful to you depending on what you aretesting but I will show how to test for it simply because a multi-meter usually has it.

(Testing for frequency is done just as you would a voltmeter. You must touch the tip of the test probesto the inside of the wire or use terminals of the electrical device as test points. With the multi-meterset to (Hz) you will be able to read how often per second the electricity switches. The reading on themeter shown is 60hz means it switches from high voltage to low voltage 60 times per second.)

Note: The Hz setting can only be used on a circuit that switches the power on and off very fast. Anormal everyday circuit that just stays either on or off will read nothing if you try to use these settingson it.

(Testing for Duty Cycle is done just as you would a voltmeter. You must touch the tip of the testprobes to the inside of the wire or use terminals of the electrical device as test points. With the multi-meter set to (Duty) you will be able to read the percentage of on time the electricity switches. The

reading on the meter shown is 50% meaning the on time and the off time are the same length of time.)

Note: The Duty Cycle setting can only be used on a circuit that switches the power on and off veryfast. A normal everyday circuit that just stays either on or off will read nothing if you try to use thesesettings on it.

Ch.6: TemperatureThe final Dial setting you may have on your meter is the Temp setting. This is self-explanatory. Youcan measure temperature of a surface using the special test probe provided.

In this test setting you remove your normal test probes and install a temperature probe in their place.Let’s take a look at what a temperature probe looks like and where it goes connected to the meter..

(This is an example of a temperature probe usually provided with the purchase of a multi-meter witha TEMP setting. The probe goes in the place of the normal red and black test probes.)

(Once the dial setting is on temperature and the probe is connected, it is simply a matter of touchingsomething with the end of the probe to get a temperature reading off it.)

This setting is probably the easiest to use. The only thing I have noticed about the temperature is thefact that many will not measure a temperature unless it is physical touching something. That meansyou might not be able to measure the outside air temperature with it.

Conclusion: (Summary & Ending Words)Reading this book was only the beginning. I only aimed to teach the basics of how to use each setting.There are far more skills you will come to learn that will make you very good at the settings of themulti-meter and using them to troubleshoot the various electrical electrical issues there are. I havemade more books to cover all the advanced subject and issues more in depth. Keep an eye out fornew books explaining other electrical subjects you might feel confused about. Stay Tuned and Thankyou for reading.Good luck.