Hi, I am Mark Donovan from HomeAdditionPlus.com and today, I am going to talk about home electrical circuit testers. Now, when you are working with wiring in your home, it is extremely important to employ safety precautions.
It starts first with turning power off at the main circuit panel for the particular outlet for switch of the appliance or fixture that you are working with. But second of all, it requires one level of additional precaution which is to actually test to make sure power is indeed off at the switch or the outlet or the fixture with some electrical type of tester equipment. What I will do is to show you two very popular types of electrical tester on the market today. They are very easy to use, low cost, and are absolutely a necessity when working with home electricity.
So the first electrical circuit tester I would like to show you is this High Voltage volt tester. It comprises of two lights, one for showing 120 volts. The other is for showing 240 volts. It requires no battery and it is $10.00. And to use it, you just hold on to the leads on the insulated portion. You do not want to touch the metal portion. And you insert it into the outlet or switch. And if there is power on, the light lights up here indicating that indeed the power is on to the circuit. You definitely want to use one of these items or when you are working with high voltage electricity, you could turn off the circuit breaker but accidentally turned off the wrong one or find out that there is more than one circuit breaker driving the outlet or switch box. So you want to make sure that indeed power is off at the destination source before you remove the cover plate.
The next electrical circuit tester I want to show you is this Digital Multimeter. It is a very powerful tool. You can use it for not only measuring a high voltage AC, but also high voltage DC, you can do connectivity test for measuring ohms and resistance. And you can also do current measurements. For this particular application, all you do for checking high voltage to an outlet, you plug the black lead into the common on the meter, the red lead into the voltage socket and then you dial in the particular type of voltage you are looking for. In this case, we are looking approximately of 110 to 120 volts AC so we set the dial on it and we have missed a large digital rate. So again, holding on to the probes with your fingers not touching the metal, you insert them into the outlet and you can see here approximately 111.8 volts of AC going across this outlet. So again, this outlet is indeed on and this is a type of tool that you would like to use to confirm the power is indeed off at the outlet after you supposedly turned it off properly at the circuit breaker box.
Another advantage of a digital mulimeter is for using it for doing connectivity measurements. Particularly, this is useful when wiring a house and you got romex cable or multiple romex cables coming into an outlet box and then going off to other outlet box and you are unsure of which romex cable is referenced to another romex cable further up the stream in the circuit. When you have additional multimeter set for a resistant measurement, when the two probes are separated, you will see that there is a reading of one or basically it is open, and it is in a very high level of resistance. If we put the two probes together, you will see that the resistance goes to zero. We basically cut it short. Again, if you have a piece of romex cable that is connected in one outlet box and the other one is connected to another outlet box, and let us say at multiple romex cables coming to each box, sometimes it can be tricky to figure out which romex cable is going to a particular other box.
So what you can do is, you can tie together and this is done with an unpowered circuit of course as you can tie together two in the wires together in this case, the neutral and the hot. And then on the far end, you can use your probes on the white and black to indeed find out whether or not you got connectivity. And as you can see here, we are able to identify that indeed this black and white wire shorted together and that is because we tied them together at the far end. So now we know that this romex cable relates to a particular wire in the other side of the room in another outlet. And so now we can label the outlet properly or label the Romex cable properly so we can complete the wiring of the switch or outlet.
So the next time you plan in doing electrical wiring in your home, again, make sure you exercise extreme caution by turning power off first in the circuit panel box. Then using some form of electrical circuit tester, confirm the power is indeed off at the outlet or switch, or fixture before actually taking the cover plate off. The high voltage test probe again is under $10.00 device. Digital Multimeter, you can get anywhere from $10.00 to $30.00 or so.
So if you have any other home improvement questions, visit us at HomeAdditionPlus.com today.
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