Testing home electrical outlets takes a few simple, and relatively inexpensive devices

The DIYer has many tools at his/her disposal to test electrical outlets and switches and to aid in replacement, but the wise choice is always to call in a professional electrician

DENVER, CO – Electricity is nothing to mess with as anyone who has ever received a shock can attest. Still, homeowners and handymen far and wide believe they can go to the internet or the big-box home improvement store and stock up a weekend’s worth of journeyman electrician and save a few bucks on a professional service call. That’s okay. There are a few electrical things the layman can perform, and we professional electricians know all too well that we’ll get called out on a good percentage of those DIY electrical situations in any case.

But that doesn’t mean we want you to hurt yourself. Quite the contrary; we like an informed client base, just not one in bandages.

One of the main things the DIYer electrician needs is the ability to know if a circuit is hot – is that electrical outlet working?; is it wired properly?; is there “juice” running through that switch?

Of course, if you’re planning on replacing a plug or a switch, it is important to know if there is electricity running through there if for no other reason than you want to make sure the juice is cut before you start taking it apart. The easiest first step is always to plug a lamp you know is working into the plug to see if it the plug works. You can also do this to an outlet that is connected to a switch – plug in a lamp and flip the switch. You’ll want to have this lamp on when you go to the circuit breaker to make sure you’ve cut power to the right circuit before you attempt to rewire a switch or plug.

There are also handy tools you can find at pretty much any hardware store or big-box home remodeling center that can test not only if electricity is running to a circuit, but what amount of electricity and whether the plug or switch is wired properly. Switches and plugs that are wired backwards – called “reversed polarity” – will still work, but they are not safe. Keep in mind that these testing devices are not fool-proof; when in doubt, better to leave it alone.

There are a few basic, and relatively inexpensive, electrical testing tools out there that can help in the detection of bad outlets and switches. The simplest is a pocket voltage tester, which looks a little like a fat ballpoint pen. Some have on/off switches on them, but you simply touch a wire, a wall outlet or anything electrical and a light comes on in the voltage tester and it chirps or buzzes in the presence of electricity. Some of these testers are “non-contact,” meaning that they only have to be close to electricity to sound off. In some cases these voltage testers determine the strength of the voltage as well, and in that case you want one that tests up to 500 volts.

There is also a device called a two-wire voltage tester, often called a “neon tester” because it has a neon bulb that lights up when electricity passes through it. It features two wires, or probes; push them into the hot and neutral slots (the wide slot is neutral) and if the light come on, the outlet is live. You can also check any 110 volt connection by touching one probe to a ground (the white wire, a ground screw or the neutral connection), and the other probe to the hot wire, usually black or red. Best to try this device in a circuit you know is live first, just to make sure it’s working.

In most homes these days to be fully up to snuff on testing the electrical, you have to have the ability to test those three-prong outlets and also the Ground Fault Circuit Interrupter (GFCI) outlets. GFCI outlets are now required by code in most jurisdictions for use in kitchens and bathrooms or for any outlet that is within 15 feet of a water source. They are the plugs that contain an internal breaker which trips instantly when it senses a short.

A receptacle tester and a GFCI or ground fault circuit interrupter tester (they look like a plug with lights on them) can show if an outlet is wired properly, and also if it is live just by plugging it in. A GFCI outlet may be wired in a branch circuit, meaning that other receptacles or devices might be wired on the same line. Those downstream from the GFIC, if it is wired properly, will lose power if the GFIC trips, so if you have lost power in a circuit it may be because a nearby GFIC has tripped. All outlets upstream, toward the power source, are not affected by the GFIC. (GFIC’s should be tested regularly, about once a year, by pressing the “Test” and “Reset” buttons on them. If you press the “test button and nothing happens, the GFIC needs to be replaced. If the outlet pops in a test, it is miswired and should be fixed immediately.)

For the three-prong outlets, you can use any variety of multimeter for testing grounding and polarity. In the regular plug portion of the outlet, the short slot should be the “hot” slot, the long slot the neutral, and the U-shpated slot the ground. Set your meter in the 200 volt range, place one probe in the U-shaped slot and the other in the long slot. The meter will read less than 1 volt if it is installed properly. When you move the long-slot probe to the short “hot” slot the meter should read 120 volts. If the readings are opposite, the outlet is wired in reverse and should be rewired.

Electricity can be very dangerous, even in small voltages, and none of the equipment mentioned here is foolproof in ensuring there is power or, more importantly, no power before work is done.

Of course, the wise choice always is to call on your professional electrician like Allstar Electrical Services to perform these tests and do any of the necessary fixes. It saves the DIYer from the anxiety of electrocution, and professionals can also quickly spot other potential hazards in your electrical system.

For all of your home electrical needs, visit www.allstarelectrical.com or call 303-399-7420.

Allstar Electrical Services is a BBB Accredited Business. Click for the BBB Business Review of this Electricians in Denver CO
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