Picture of EVERYONE Needs a Multi-Meter
A multi-meter can save the average person a lot of money over a few years, even though ladies who choose to buy one may not carry it in their purse when going out for the evening. You will often be able to solve many problems yourself in less time than it would take to get a technician to come to your home. This Instructable will show how to do that simply and easily.

I often meet handy people, both men and women, who do not go near to anything electrical because they are frightened of electricity. It is good to have a strong respect for electricity. It is also good to know how to make basic electrical measurements around the home. A multi-meter is the tool every home ought have. They eliminate the guess work from so many things and can save a lot of money. 

A suitable multi-meter for occasional use around the home and automobile can be had for less than $ 5. This link is to a very inexpensive meter that includes some functions found only on meters costing twenty times more just a few years ago. More expensive meters do not necessarily have more features. They give greater accuracy for professional work, and they are more rugged in their construction and durability.

Step 1: Will I electrocute myself?

Picture of Will I electrocute myself?
No, that will not happen if you follow a few simple precautions. Most home uses of a multi-meter will be done with the power disconnected, or with very harmless low voltages. Regardless, you will always handle the probes by their well-insulated, completely safe plastic "handles." Usually, you will hold one in each hand.  

The black probe is normally associated with the ground or negative terminal. The red probe is normally associated with the "hot" or positive terminal. For household uses illustrated in this Instructable you can ignore all of that and use either probe on any terminal. 
1-40 of 198Next »
aoke1 year ago

Thanks for your great article friend, i get new information, new ideas to do somethings, i hope you will share again, i keep waiting for next post, thanks. http://goo.gl/3hWprI

Phil B (author)  aoke1 year ago

Thank you.

spylock1 year ago
You are right,and as far as carrying one in the purse, ladies who may not be so bold as to carry the larger meters in the pocket book may be interested to know that Radio shack makes a nice little meter that is small around 4x3x1/2.It folds in half, it is kinda expensive,I paid about 30.00 for one a few years back as I needed it often for work,and it was small enough to carry in my shirt pocket.Very good advice,for all ,good thinking.
Phil B (author)  spylock1 year ago
Thanks. The photo of the meter sticking out of a woman's purse with her cosmetics nearby was a little tongue in cheek joke. I ran it past a lady preschool teacher I know and she thought it was pretty funny.

I have seen some pocket meters like you describe. They would be great for what you describe. My brother gave me a basic Radio Shack meter that does not fold, but is about 3/4" x 1" x 6" with an insulated fixed probe on the front end and a wire lead near the front end. It is small enough to carry in a pocket case for eyeglasses. I have often taken it with me when I travel.
spylock Phil B1 year ago
Sorry I didnt catch on,the reason I took it serious is because my mothers purse had a small screw driver set,keychain type multi tool,a credit card tool with many uses,well you get the just of it.She didnt however have a meter as she was scared of electric;its just my Pops and myself now,and we ran a small plumbing/drain cleaning company from 1987-2010.We are some do it ourselves kinda people.It is kinda funny now that Ive thought about it,but I think man and woman alike should at the very least carry a pocket knife,and I like your instruct.I hope ladies read it and take it to heart.
Phil B (author)  spylock1 year ago
There are probably a few ladies adventurous enough to use a meter, even if for a few basic things. Imagine a woman in a group including a few men. The TV remote does not work. She removes the batteries, pulls a VTVM from her purse and tests the batteries. In a few minutes the remote is working again. Some will admire and respect her. Others will feel outclassed and hate her.
spylock Phil B1 year ago
I would be of those who respect her for sure,I respect anyone who will at least take a wack at it,and those who dont know how,but ask get my respect as well.
Phil B (author)  spylock1 year ago
My wife was the first woman I ever met who knows what a wood lathe is. Her grandfather had one. I had bought one by saving my allowance in junior high. I still have it almost 55 years later.
spylock Phil B1 year ago
My mother knew what a forge was,and when I was making mine out of an old wheel hub,she told me that a wheelbarrow made a much better one,course I didnt know she even knew what a forge was,but her grandmother who raised her was a Hatfield,and up in west Virginia they had to make do.Ill tell you Phil,woman folks will surprise you sometimes,wont they?
J,R,D, Ltd2 years ago
Well, it did save you money in a way because you didn't have to pay a mechanic $60-$100+ an hour to find that problem.
Phil B (author)  J,R,D, Ltd2 years ago
You are quite correct. I am so accustomed to doing whatever work I can on my car that I do not even think about what I would have paid at a garage, not to mention towing the car to the garage. Thank you for looking and for your comment.
fretted2 years ago
I've got one of these meters from harbor freight i'm glad you wrote this Ible now i can use it where i didn't have a clue before how to start now i know

Thanks for a great Ible
Phil B (author)  fretted2 years ago
Those are not bad little meters for home use. I think I have one,too; but, I got mine at Home Depot and paid a lot more for it. I did this Instructable for people in your situation.
fretted Phil B2 years ago
Before i read this i really didn't have much of a clue how to use it on much thanks for this ible now i understand a-lot more about it and how to use it now if i could just get a handle on basic electronics i''ve got a-lot of ideas for LED's and and some cool steam-punk stuff I've fallen into this steam Victorian era kick and can't seem to throw it off i find some of these things very fascinating to build and goof around with and of course my nieces love the stuff ...
Phil B (author)  fretted2 years ago
There are some good basic books on electronics for the person who wants to learn on his own. There are also some good tutorial sites on-line. Here is a link to a pretty good circuit simulator that allows you to test circuits without the expense of buying real parts. If you go to this link, you can download an older version of the US Navy Electronics Course for free. I apologize for taking so long to respond to your comment. I wish you well.
fretted Phil B2 years ago
Hey np problem and thanks for the links i'll be checking them out !
Phil B (author)  fretted2 years ago
When I was much younger I was very interested in radio circuits and wanted to learn all about them. Years later I met someone who had studied electronics by means of a famous (at the time) mail correspondence course. He said he did not use most of what he learned, but found what he had learned about power supplies gave him all he used and needed. Many things these days run on 5 volts, which is the exact output of a USB port and also an old phone charger. Once plug-in power supplies contained transformers with real copper wire. Now most are switched mode power supplies. The older style allowed adding a variable voltage regulator chip configured to the exact voltage you needed. The new style does not work with the regulator chips (as best I can determine). I wish you well. You will have fun with your electronics learning. Be aware some published circuits have bugs in them and when they do not work, it is not your fault.
fretted fretted2 years ago
lol np = no
i was subscribed to a magazine that had free DMM coupons for harbor freight, i think i have 3 freebies now, one for my tool box, one for my car, one i gave to my dad. i have a more expensive DMM for my electronics tool box. i find a reason to use one all the time
i was subscribed to a magazine that had free DMM coupons for harbor freight, i think i have 3 freebies now, one for my tool box, one for my car, one i gave to my dad. i have a more expensive DMM for my electronics tool box. i find a reason to use one all the time
i brough a multimeter to school, because you never know ehn you might need it and people kept asking waht it was, i was famouse for a little bit
Phil B (author)  The nerdling2 years ago
One day they will wish they had been more like you and learned to use a meter. Thank you for looking.
I can't tell you how many times I have pulled my meter out only to have someone ask "what's that?". I have saved time and money for sure. Awesome and informative instructable sir.
Phil B (author)  jchamberlain2 years ago
Thank you for looking and for commenting. This Instructable attempts to explain uses for a meter I have found in everyday needs. I expect my experiences are close to those of others. Have you used your meter for some common needs I missed? Thank you again.
I have several TV monitors around the house linked with coax cable. Sometimes in order to troubleshoot them I use the continuity setting, I have someone short out one side using metal to touch the center pin to the outer connector. I then use the two probes to check my various cables to identify them.

This also allows me to identify which cable connects to which device at friends homes when helping them connect TV, satellite or other antenna.

Phil B (author)  jchamberlain2 years ago
I have a spool of bell wire I use to connect to a wire at a wall box a couple of rooms away. The continuity tester or the Ohms scale lets me check for a break in the wire inside the wall. I once found a broken wire inside a ceiling box this way, even though there was no visual hint of the break. Thank you for the information on how you use your meter.
darman122 years ago
Just the title made me proud to own one :)
Phil B (author)  darman122 years ago
I am glad you already have a multi-meter. You will find a lot of uses for it throughout your life.
tim_n2 years ago
thanks for the overview. I've read this and the sparktronics tutorial and it all makes a lot of sense - though I didn't read anything about the different sockets in yours (10A?) for mains voltages?

Either which way, I'm off to do some soldering today and play with the multimeter to make an RFID arduino door lock!
Phil B (author)  tim_n2 years ago
Generally, you can do most of your work with the COM and + sockets. But, when measuring the current flow in a circuit you need to match the current type, AC or DC, on the dial with the current type in your circuit. You also need to use the socket appropriate to the current level expected. Recently, I wanted to check the parasitic current draw my automobile makes from its battery when everything is supposed to be "off." If the door has been opened recently and the interior dome light is "on," the current draw rose to 2.99 amperes. That meant I needed the dial set to the 10 A DC range. It also meant I needed to use the 10 A socket and the COM socket. If I had been measuring current in an AC circuit and it was expected to be more than milliamperes, I would have needed to use the same sockets, but change the dial to the 10 A AC setting. Which socket to use more concerns the type and level of current expected than the voltage.
Nano_Burger3 years ago
You can add this use to your list of common uses for a VOM (common for me anyway).


I use my VOM to repair cameras all the time. Luckily, I'm dealing with pretty low voltages and amperages to make it absolutly safe. The only risks are when dealing with photo flash capacitors.
I have a vague memory when on holiday with friends of breaking open a disposable camera and taking the AA battery out for my walkman. Saw what I thought was a 2nd AA battery and broke the camera open further to get it out.

Que burst of light from flash and large electric shock. It was the biggest capacitor I'd seen at 11 years old, same size as an AA battery.

Most people might have stopped playing with it at this point, but I recharged it and said to my mate 'go-on, touch those two wires'

He didn't die and he learnt a life long lesson on what not to touch in electronics.
Phil B (author)  Nano_Burger3 years ago
Thank you for your comment. I read your Instructable on checking trigger voltages of electronic flash units. I have two digital cameras, neither of which has a hot shoe. In the days of film cameras I did have a couple of Vivitar 283 units and used them with slave triggers for multiple flash. What I had really been looking to find was a way to use my 283s with a slave trigger that would get around the pre-flashes on most built-in flash units used on cameras like mine. I once found a schematic for a home built delaying trigger and built it, but it did not work.

When I did this Instructable on using an electrical meter, I hoped people would take the basic things I showed and expand their usage to special purposes like yours.
raziz2 years ago
i've seen a few old-timer mechanics turning on the wiper to check the battery strength when a car is having trouble starting.. i guess the wiper cranks more amps then the headlights.. once a car gone dead on me, even the instrument panel was blacked-out, it turned out the alternator had failed completely..
Phil B (author)  raziz2 years ago
I am sure that would work. I used to buy repair manuals by Motor's. They always had excellent general diagnostic and repair material in the front section of the volume. Another technique was to turn on the headlights and have someone attempt to crank the engine. The engine should turn over with the lights dimming only slightly.
tridecagon2 years ago
Another example of how a multimeter (and troubleshooting skills) can save a few hundred bucks.
ac-dc4 years ago
It is not true that corrosion could be a problem if it is not visible. For there to be enough corrosion to cause a problem it is progressed to the point it is very plainly visible and there is no need to check it with a multimeter as it is obviously in need of cleaning.
Phil B (author)  ac-dc4 years ago
I am sure I remember reading that not all corrosion is visible. Before responding I did a search and found someone had problems with corrosion he could not see without removing the battery connectors. I have found the newer side post terminals can be quite corroded, but the corrosion remains covered and not visible from a quick glance under the hood.
This is true, corrosion can "hide" in the contact areas between the terminal and post. What your doing is called a "voltage drop test". It's a quick and easy way to locate where a bad connection is raising havoc. There are several good videos showing how to use a voltage drop to solve real world problems, including cars that won't start with battery terminals that look clean!
Phil B (author)  79spitfire4 years ago
Thank you. I assume the videos are at YouTube. Is that correct?
1-40 of 198Next »