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Everyone use electricity to power our homes, business, televisions , lights, etc. With AC or “Alternating Current” , the current alternates in direction on a regular basis.  This has shown to be a better way for providing electricity than “Direct Current” Electricity or DC Electricity.  This is because the voltages can be changed if needed. Using AC electricity in homes also allows for other devices to be used

While direct current (DC) electricity flows in one direction through a wire, AC electricity alternates its direction in a back-and-forth motion. The direction alternates between 50 and 60 times per second, depending on the electrical system of the country.  This change happens in a cycle.  Each cycle is also called a Hertz (Hz).

AC electricity is created by an AC electric generator, which determines the frequency. What is special about AC electricity is that the voltage can be readily changed, thus making it more suitable for long-distance transmission than DC electricity. But also, AC can employ capacitors and inductors in electronic circuitry, allowing for a wide range of applications.

We say AC electricity instead of simply saying AC, since that is also the abbreviation for air conditioning. You need to be specific to avoid confusioning issues and to avoid any misunderstandings while discussing a topic like this.

With an AC generator, a slightly different configuration alternates the push and pull of each generator terminal. Thus the electricity in the wire moves in one direction for a short while and then reverses its direction when the generator armature is in a different position.

The charge at the ends of the wire alternates between negative (−) and positive (+). If the charge is negative (−), that pushes the negatively charged electrons away from that terminal. If the charge is positive (+), the electrons are attracted in that direction.

AC electricity alternates back-and-forth in direction 50 or 60 times per second, according to the electrical system in the country. This is called the frequency and is designated as either 50 Hertz (50Hz) or 60 Hertz (60Hz).

The regular back-and-forth motion of the electrons in a wire when powered by AC electricity is periodic motion, similar to that of a pendulum. Because of this periodic motion of the electrons, the voltage and current follow a sine waveform, alternating between positive (+) and negative (−), as measured with a voltmeter or multimeter.

There are distinct advantages of AC over DC electricity. The ability to readily transform voltages is the main reason we use AC instead of DC in our homes.  The major advantage that AC electricity has over DC electricity is that AC voltages can be readily transformed to higher or lower voltage levels, while it is difficult to do that with DC voltages.  Since high voltages are more effecient for sending electricity great distances, AC electricity has an advantage over DC. This is because the high voltages from the power station can be easily reduced to a safer voltage for use in the house. Changing voltages is done by the use of a transformer. This device uses properties of AC electromagnets to change the voltages.

AC electricity also allows for the use of a capacitor and inductor within an electrical or electronic circuit. These devices can affect the way the alternating current passes through a circuit. They are only effective with AC electricity. A combination of a capacitor, inductor and resistor is used as a tuner in radios and televisions.

A voltage tester is equipped with two probes and a light bulb but has no power source.  The 120/240 voltage, or neon-light that shows that there is voltage, lights up when voltage is present.  This device is used to find the incoming hot wire when more than one black wire is in a box and to check for proper grounding.

If you attempt to work inside of a service panel, and this is not recommended for those that are not skilled in electrical work, it is necessary to look for any current leakage, for any electricity that is outside of its proper place.  This should only be attempted after all power to the panel has been turned off.  Once you are sure that there is no electricity coming in to the service panel, remove the panel cover.  Touch one of the voltage tester probes to the ground/neutral busbar (bus) (a busbar in an electrical power distribution refers to thick strips of wire that conduct electricity in, for one, a service panel.)  Touch the other probe to an open space first on one, then on the other hot bus.  If the tester lights up, call an electrician.

Once you have checked that the power is off, insert the probes into the slots of the outlet.  If the bulb does not light up, the power is off.  Test both openings of a duplex receptacle (double container.)  After this, remove the cover plate, and touch probes to bare ends of each pair of black and white wires attached to the receptacle.  Tester should not light.

It is necessary to check for grounding.  Grounding is the process of removing the extra electrical charge on an object by transferring electrons between it and some other item of substantial size. When a charged object is grounded, the excess charge is balanced by the transfer of electrons between the charged thing and a ground. A ground simply said is an object which serves as an outwardly substantial reservoir of electrons.  The ground is capable of transferring electrons to, or receiving electrons from, a charged object in order to neutralize that object.

To check for grounding in a receptacle with power on, put one of the probes in the short (hot) slot.  Then touch the second probe to the bare metal cover plate, or to the plate screw, or insert the second probe in the grounding slot, if there is one.  If tester shines weakly or not at all, the receptacle is not well grounded.  Then, with the power off, remove the cover plate and look for a loose grounding connection.

To test for the electric power at a switch, first turn off the electric power to the circuit and then remove the cover plate over the receptacle.  Place one of the probes on the metal box, or if the box is nonmetallic, place one of the probes on the bare grounding wire.  Touch each switch terminal with the second probe.  If the tester lights up, then there is power coming in to the receptacle.  If this is the case, go back to the electrical service panel and turn off the right circuit.

If you need to find the right incoming hot (electrified) wire in an electrical box, cut power to the circuit.  Remove switch, receptacle, or fixture from the electric box.  You need to bend the loose electric wires away from each other and the electric box because you need to keep these wires from touching each other and from touching the box.  After this has been accomplished, restore the electric power.  Cautiously, touch one of the probes to the metal box (or to the grounding wire if the electric box is made from plastic.)  Then touch the second probe to each black wire.  The voltage tester should light at the hot (electrified) wire.

You need to learn what circuits are needed for a typical kitchen, whether you are building a new home or just remodeling an older home.  There are some basic circuits that are needed in a kitchen area to supply an effective amount of power to the appliances that will be used. Here is a list of the most commonly used circuits in a kitchen.

The refrigerator requires a dedicated 20-amp, 125-volt circuit. You may only have a smaller refrigerator, while someone else may have a 25 cubic foot side-by-side refrigerator that draws more power. A 12/2 NM wire with a ground is required.

An electric range will need a dedicated 250-volt, 50-amp circuit. That means that you’ll need to pull a 6/3 NM cable or #6 THHN wire in pipe to feed the range.  If it’s a gas range, it will only require a 125-volt receptacle to feed the range, although while in the construction phase, it’s a good idea to add the electric range feed while the walls are open just in the event you ever want to purchase an electric range.

The dishwasher circuit should be a dedicated 125-volt, 15-amp circuit. It is fed with a 14/2 NM wire with a ground. You may elect to feed the dishwasher with a 20-amp circuit using 12/2 NM wire with a ground.

Food disposers do the dirty work, clean up the messes after meals. A dedicated 15-amp circuit is required being fed by 14/2 NM wire with a ground. You may elect to feed the disposer with a 20-amp circuit using 12/2 NM wire with a ground.

The microwave oven needs a dedicated 20-amp, 125-volt circuit to feed it. This will require 12/2 NM wire with a ground.

You will also be using small appliances that sit on your counter tops and they draw additional electrical loads. Atop your countertop, you will need two dedicated 20-amp, 125-volt circuits to run your small appliance loads. You know like toasters, electric griddles, coffee pots, etc… Although there may be more than two outlets on these circuits, two circuits is the minimum. That’s not to say you can’t add more circuits if your needs require them.

Of course, a kitchen wouldn’t be complete without a lighting circuit to brighten the cooking area. A 15-amp, 125-volt dedicated circuit is required to power the ceiling fixtures, can lights, under cabinet lights, and strip lights if you have them. Each set of lights should have their own switch giving you the option of which ones to turn on.

As homeowners, we often overlook light fixtures in our home when it comes to maintenance. We walk in the room and flip on the light switch, assuming it will always light and be there for us. However, that isn’t always the case, as we all know. Sometimes common electrical problems can cause the problem, or it may just be that a bulb burned out. But how are we to know? Here is a list of common problems and some recommended repairs to keep the lights shining brightly in your home.

Let’s take the ceiling light fixture. You walk in and the bulb will not light. First, check the light bulb first. It may have burned out. Replace the bulb. Check to see if the bulb is tight in the socket; check the socket tab in the center of the socket. You may have to pull up on it in order for it to make contact with the bulb; check the connections at the switch and make sure that they are tight. Be sure that the power is off to the circuit that you are working on; the check the connections at the light and the breaker panel to be sure they are all connected tightly.

Another problem homeowners may encounter is flickering lights. If the bulb flickers on and off it usually means that the switch contacts are getting bad. Usually you’ll be able to hear a sizzling or crackling sound if the switch contacts are bad. In this case, replace the switch. It also could be that the connections are loose. This could be on the switch, at the panel, or in the junction box of the light. There also is the possibility that the connections to the light socket could be loose. Check all of these points and tighten if necessary. If the socket connection is loose, replace the light socket.

Recessed lights, or can lights can also pose electrical problems. Check the size of the bulb in the socket. Make sure the wattage of the bulb doesn’t exceed the recommended wattage rating for the fixture. The maximum wattage will be listed on a tag on the fixture or socket.

The limit switch turns the unit off when the temperature reaches an unsafe level. Over- sized bulbs will radiate an excessive amount of heat and could potentially cause a fire if the limit didn’t shut off the light. It is possible that the limit switch may need to be changed if the correct bulb is in place. You also may need to pull the can light out and make a space above the can light. If the insulation is packed to tightly on top of the light, proper ventilation cannot take place. This will trip the thermal.

You may have a fixture with built-in switches or even pull chains. First, check to see if the bulb is not working. If this is the case, change the bulb. If this is not the case and it is the switch that is not working, check the connections on the switch to make sure they are all tight. Remove the switch from the circuit and test between the wires with an ohmmeter. Toggle the switch and see if it changes values on the ohmmeter. If not, replace the switch. Check the wires to the socket. If they are loose or have a burnt appearance, replace the socket

Electrical codes are in place to protect you, the homeowner. These general guidelines apply to new installations and will give you the basics of what electrical inspectors are looking for and what you need to know for your house. Be sure to check with your local electrical inspector because local electrical codes may vary from the list provided. In the case of existing housing, the codes will apply if you are updating a home, and it requires an electrical update. You should also think of up-dating the wiring in your home if it is old and unsafe and it has become a danger to your family. Faulty wiring has caused many fires and even fatalities.

Bathrooms use a lot of power and may need more than one circuit. Mainly, because you may have a curling iron, razor, hairdryer, and the combination light, fan, and heater all running at the same time. The combination fan, light, and heater should have its own 20-amp circuit. Likewise, the outlet should have its own 20-amp circuit. All outlets in bathrooms should be GFCI’s. Light fixtures should be covered with lenses or globes and moisture resistant if placed in a shower or tub area.

A kitchen should have a separate circuit for each appliance with a motor. The microwave, refrigerator, garbage disposal, and dishwasher would be the major appliances included. Generally, the code requires that you install a minimum of two receptacle circuits in the area above the counter top. An electric range, cook top, or oven must be wired to a dedicated 240-volt circuit.

The living room areas and bedrooms require that a wall switch be placed beside the entry door of the room so that you can light the room before entering it. It can control either a ceiling light, a wall light, or an outlet connected to a desk lamp. The ceiling fixture must be controlled by a wall switch and not a pull chain type light. Wall receptacles should be placed no farther than 12 feet apart. Dining rooms usually require a separate 20-amp circuit for one outlet used for a microwave, entertainment center, or window air conditioner.

Special care is needed in stairways to ensure all of the steps are lighted properly. Three-way switches are required at the top and bottom of the stairs. If the stairs turn, you may need to add additional lighting to accommodate the area to be lit.

These areas can be long and need adequate lighting. Be sure to place enough lighting so shadows are not cast when walking. Remember, hallways are often escape routes in the event of inclement weather and emergencies. A hallway over 10 feet long is required to have an outlet for general purpose. Three-way switches are required for the two ends of the hallway. If there are more doors throughout the hallway, say a bedroom or two, then you may want to add addition four-way switches to the circuit outside the door of each room.

Closets must have one globe-covered fixture controlled by a wall switch. Exposed bulb fixtures, like pull-chain fixtures, get hot and come in contact with clothing or other combustible materials stored in closets. Although your existing home may have these fixtures, it is recommended that you change them for safety reasons.

In the laundry room, the washer and dryer should have its own 20-amp receptacle. In the case of an electric dryer, a separate 240-volt circuit should be installed.

Inside the attached garage there should be at least one switch controlling the lighting. It is recommended that three-way switches be installed for convenience between the doors. This lighting should be in addition to any garage door lighting that you may have. Garages need a separate circuit for at least one outlet. This is generally required to be a GFCI outlet. You should check your local code to be sure. When in doubt, make it a GFCI. Any outside outlets connected must be either a GFCI outlet or an outlet connected to a GFCI breaker.

Remember that the electrical codes are in place for your safety. Although you may believe that they are overkill at times, these practices save lives everyday. When it comes to electric safety, don’t become a statistic. Follow the rules of the codes and be sure to have your local electrical inspector give you the green light on your wiring for the safety of your family’s sake.

The National Electrical Code says that no splices are allowed outside of junction boxes. However, it seems that older homes were not built with this in mind. They have lots of wires hanging out that are not in a protective box. A wire splice should always be placed in a protective box and covered with a box cover. Before correcting this problem, as with any other electrical fix, turn the power off to the circuit that you’ll be working on. This is the very first thing that you should do when attempting to work with electricity. This may involve turning off a circuit breaker or unscrewing a fuse. Safety should be your first concern. Use a tester to check the connection and see that it really is off before proceeding. Check for power between the hot wire and the neutral wire to see if there is any power present.

Once you know the power is off, take the wire splices apart so that junction box can be added.

To install a junction box, first pull the two wires back so that the box can be added. Remove two of the box’s knockouts to allow the wires access to the box. Install cable connectors in these holes and tighten the locknut with pliers. The wire will slide into the connector and can be tightened with a screwdriver. Now, install two screws through the small holes in the back of the box to secure the box to the wooden joist.

After the box is secure, use linesman pliers to twist the wires together. To do this, join like colors, black to black, white to white, bare copper to bare copper and twist them together evenly. Add a wire nut to cover the connection. In this case, I’m using red wire nuts to make the connections. You may want to use a green-colored wire nut on the ground (bare copper) connection to symbolize the ground connection.

Once the wires are covered, it is time to install a cover plate. The wires must now be formed into the box so that the cover will go on effortlessly and the mounting screws do not screw into the wire insulation. Tuck the wires into place and place the cover over the two mounting screws. Tighten the screws and you’re ready to turn the circuit back on. After restoring power, go to the device that the splice is feeding and make sure that the circuit is indeed on. If so, you have successfully installed a junction box and made your home safer in doing so.