How to Move an Electrical Outlet or Light Switch
Electrical outlets and light switches sometimes must be moved during a remodeling project. This often happens when a closet has been added or a door moved. Many times this will leave the light switch on the opposite wall or a large section of the room without an electrical outlet because the original one is now in the closet. In the long run conveniently placed outlets and switches are worth the effort required to move them. With care this can be safely done by homeowners.
The tools you will need for this project include an electrical meter, flat and Philips screwdrivers, pliers, razor knife and clean up tools. For the electrical part of this project you will need wire, electrical box, wire nuts, and a blank outlet cover. The electrical box you want will be the one with locking tabs. It is possible that you will have drywall damage. If so then you will also need drywall repair materials and tools.
Safely should always be the main concern when working with electricity. Never work on a live circuit. You must always turn the power off at the breaker box before starting. Sometimes the breaker box does not have the circuits labeled correctly or marked at all. To verify you have the correct circuit you should turn the light switch on or plug a light into the outlet to be moved. Flip the breaker onto the off position. The light should no longer be on.
Remove the wall plate cover. This will expose the outlet or switch. Look at the sides. You should see some screws. Switches will have two usually on one side unless it is a three way switch. Electrical outlets will usually have two on each side. In most cases the wires are connected to these screws but sometimes the wires are plugged directly into the back. There should also be a green ground screw near the top. Turn you electrical meter on. Set it to read AC Volts. Place one lead of the meter to the ground screw. Carefully set the other lead against one of the screws. Check your meter to verify that the electricity has been turned off. Do this for each of the remaining screws. Only after you are 100% positive that the electricity is off should you continue.
Unscrew the outlet or switch from the box it is in. Pull it out of the wall. Leave the wires attached for now. Examine the wires that are connected to it. You must buy the exact kind and size of wire that is used. This will be marked on the outer coating of the wire. An example would be 14/2 (14 gauge / 2 insulated + a bare ground)
Trace the electrical outlet box at its new location with a pencil. Use a razor knife to cut the drywall along the lines. Run a new wire from the hole you just cut to the old electrical box. If you need to pass by wall studs then you will need to cut a 1" strip out of the drywall for the new wire to follow. This will need to be patched later.
Push the end of the wire 5 inches into the old box through a wire access holes. Cut the end where the new box will be so that there will be 5 extra inches of wire. Push this wire into the new box. Install the new box into the drywall. Turn the locking tabs.
Strip the new wire casing back as far as possible. Remove 1/2 inch from the insulation of each strand of wire. Twist the plain copper wire around the green ground screw on the new switch or outlet. Install the black and white wires to the screws on the side in the same position as the old one. A three way switch will also have a third wire to install. On three way switches it is important that the hook up match exactly. Screw the switch or outlet into the new electrical box.
Disconnect the wires from the old switch or outlet. Twist the copper wires together. Push them to the back of the box. Use a wire nut to connect the new wires to the old ones. Connect black to black, white to white, etc. Make sure the wire nuts are tight. Push these wires into the wall. Turn the breaker on. Verify the electrical switch or outlet works.
Repair any drywall damage before you install the electrical plates. You must not cover the old outlet box with drywall. You must have access to the wire connections. After the drywall has been repaired place a blank plate over the old electrical box and a new switch or outlet cover over the new one.
This project will solve a common remodeling complaint. It looks harder than it is. With care it can be done simply, safely and with minimal damage. Above all do not fear electricity, respect it.
When it comes to air conditioning installations, there is usually very little that the homeowner can do. However if you are relatively handy you can install the electrical service to the outdoor condenser unit and then leave the refrigeration work to the professionals.
Remember that you should always check with your local building department to determine what type of permit is required for the total installation of an air conditioning system. Homeowners are usually allowed to perform electrical and plumbing work without a license. By having the work permitted and inspected you will not only increase the chances for a successful installation, you will not void your homeowner’s insurance policy and you will not have any issues when you go to sell your home in the future.
The Electrical Circuit
The electrical circuit needed to power your outdoor air conditioner condenser is typically a double pole circuit breaker in your home load center (panelboard) that goes to an air conditioner service disconnect switch and from the disconnect switch to the condenser.
A 220 VAC circuit requires two (2) vacant circuit breaker positions located together in the panelboard. From the circuit breaker you will run the appropriate size cable to the outdoor air conditioning disconnect switch. From the disconnect switch you run the wires to the air conditioner. The size of the wire depends on a few important factors; the circuit size which is determined by the unit, the length of the run from the unit to the panelboard, and the insulation on the wire. Also check the installation instructions on the condenser unit. Some models may require both 120VAC and 240 VAC; in this case you would need to run 3-conductor wire, red, black, white and a ground.
You may need to make sure that your electrical service has the capacity for new air conditioning equipment if you are adding it to an existing home. Contact your utility for more information.
Wire Size Calculator: http://www.elec-toolbox.com/calculators/voltdrop.htm
Note: The longer the circuit length the greater the voltage drop. Usually circuits over 40 feet in length need the wire size increased to the next largest wire size. For a 30A circuit you may need #10 wire and for a 45A circuit your may need #8 wire.
Tools and Materials
Voltage Meter or Tester
Drill and Drill Bits
Flat and Philips Screwdrivers
Galvanized screws, for mounting disconnect
Wire, #12, #10, or #8 and a ground wire
Flexible Liquid-tight conduit
Double-Pole Circuit Breaker
1. Mount the air conditioner disconnect on the exterior of the home as close to the air conditioner condenser as is reasonable. Ensure that it is securely fastened to the wall using proper fastening hardware for the wall material. The National Electrical Code is typically followed but may be interpreted differently by the building inspector. Usually it needs to be readily accessible and within line of sight which can mean within arm’s reach or within 6 feet. Check with you local code official for clarification.
2. The air conditioner disconnect is connected to the air conditioner condenser with liquid-tight flexible metallic conduit, sometimes referred to as “seal-tight.” The size of the conduit is dependent upon the wire size, for #10 use 1/2” conduit and for #8 use 3/4” conduit. (This is for 2 wire conductors.) Liquid-tight conduit can be purchased at electrical distributors and most home centers.
The conduit is mechanically connected to the disconnect and the condenser using the appropriate straight or 90° flexible metallic conduit fittings. These fittings transition from the PVC coated conduit to a metal fitting
90-Degree Liquid-tight fitting
Add conduit clamps within 12 inches from the disconnect and another at the last point on the wall prior to the conduit heading towards the condenser.
3. Run the appropriately sized wires through the liquid-tight conduit. While you can purchase and run sheathed cable, it is better to purchase individual conductors of the correct wire gauge and length. They can be purchased at electrical distributors and home centers. The length of the wire should be about 24 inches longer than the conduit itself.
Since both wires are conductors in 240VAC circuits, buy wires with black insulation to identify them properly. If you use sheathed cable that has one black and one white wire, you need to wrap the ends on the white wire with black electrical tape.
4. Connect the wires in the air conditioning condenser junction box.
The bare copper wire is the ground wire which needs to be connected to the green wire in the condenser junction box. This may be a lug or screw connection depending on the manufacturer. In either case the ground wire is connected to the metal frame of the air conditioner condenser.
Inside of a Condensing Unit: The liquid-tight conduit is coming in at the bottom (1), the two black conductors are connected to the relay on the left (2), and the ground wire is connected to a lug on the left side of the frame (3).
The other 2 wires supply the 220 VAC to the condenser. The location and method of connection for these two wires will be described in the installation manual that came with the condenser.
5. Connect the wires to the inside terminals or lugs in the disconnect. The bare copper wire will attach to a lug or screw that is connected to the frame of the disconnect. The other two wires will connect to lugs or screws that are identified as “LOAD”. It does not matter which load wire goes to which lug or screw. Check with your local code official to determine if they require a fused disconnect, which is not typical, or a non-fused pullout disconnect.
Pullout Service Disconnect
6. Run the wires from the service disconnect to the electrical load center. If the cable is going through an unfinished basement or in a crawl space under a home you can use sheathed cable. However, anywhere where the cable is in a location where it can be damaged it must be protected. For this reason it is better to run the wires inside rigid PVC conduit or the flexible conduit to an electrical junction box and from that point on to the load center.
Use conduit clamps to fasten the conduit to the wall or joists. In areas where sheathed cable is running through a basement the cable must secured using clamps or staples every 36 inches and within 12 inches of any electrical box or the load center panel.
7. Turn the power "OFF" at the load center. This is accomplished by either turning "OFF" the main breaker or at a disconnect switch located between the utilities electrical meter and the load center. You will most likely need to remove a “knockout” from the load center either at the top of bottom. Use a fitting to protect the wires going through the knockout hole.
IMPORTANT: Turning the main breaker to the "OFF" position does not remove all power from the load center. Power has been turned "OFF" to the individual circuit breakers, but there is still live power on the incoming lugs of the main breaker.
Remove the inner load center panel that covers the electrical connections to the circuit breakers.
IMPORTANT: When you have turned the power to the "OFF" position, ensure that there is no power at the breakers by using a volt meter.
8. You must install a double pole breaker in the load center panel. The size of the breaker depends on the electrical requirements of your air conditioner condenser. It can be 30, 45, or 60 Amp.
Double-Pole Breakers shown with red and black wires.
A double pole circuit breaker takes up two vertical positions in the load center. If you have two horizontal positions available you can move one of the current circuit breakers in order to free up two vertical breaker positions.
Note: Do not install two wires on one circuit breaker in order to free up space.
Note: You must purchase a double pole circuit breaker that is designed for your load center. There is no standard mounting configuration for circuit breakers in load centers. The front of the breaker will have the name of the manufacturer and type which is usually 3 or 4 letters.
Once you have installed the new double pole circuit breakers connect the load wires, one to each of the circuit breaker lugs.
9. Connect the ground wire to the ground bar or lug in the load center panel.
10. Replace the circuit breaker cover panel.
Leave the new double pole circuit breaker "OFF" until the installation of the air condition system has been completed by your HVAC technician.
11. Turn the main breaker or the main disconnect switch back to the "ON" position.
After the system has been completed, call your building inspector for a final inspection.
By taking the time to properly install the electrical service to your air conditioning system you can save yourself a few hundred dollars.
Circuit breakers are over current protection devices (OCPD) that are designed to break the circuit and prevent equipment damage or fire. When too much current runs through a circuit the heat in the circuit exceeds the breaker's load rating and it trips, shutting off the electrical power. Proper sizing eliminates overloads and insures safe electrical operation. Circuit breakers are designed to carry 100% of their rated current while the NEC dictates an 80% application.
A commonly misunderstood fact about circuit breakers (CBs) is related to the percentage of loading permitted by the NEC and the CB design, and why the two may be different. Let's investigate both aspects.
Circuit Breaker Design
A circuit breaker (CB) is designed and evaluated to carry 100% of its rated current for an indefinite period of time under standard test conditions. These conditions, per UL 489, Underwriters Laboratories Standard for Safety for Molded-Case Circuit Breakers and Circuit Breaker Enclosures, include mounting the CB in free air (no enclosure) where the ambient temperature is held at 40 degrees C or about 104 degrees F. Under these conditions, molded-case CBs are required not to trip at rated current.
However, a CB most frequently is applied in equipment at 80% of its rated current under NEC Sec. 384-16(c). If you understand why this requirement is in place, you'll be able to apply CBs correctly.
Since the current path, both the CB and the conductor, reacts to heat, the overall operating temperature of the equipment becomes a factor in sizing a CB in an enclosure.
Other factors that may affect this equipment operating temperature include:
1.) Size and location of the enclosure.
2.) More than one current carrying device housed in the same enclosure.
3.) Level of current each device is carrying.
4.) Environmental conditions in the area of the equipment
A circuit breaker either carries a standard rating (80%) or a 100% rating. The standard rating is subject to the NEC sizing rules. CBs that are 100%-rated are permitted to be loaded continuously at their full rating as long as the assembly is listed and conductors are properly connected.
Determine the total electrical load required for the circuit you are sizing. All electrical appliances and equipment list the operating load they need to operate properly somewhere on the component, usually on an attached sticker or plate. For example, if you are planning operate a refrigerator rated at 8 amps, a toaster oven rated at 6 amps and a microwave rated at 6 amps on the same circuit, you need a breaker that that will safely carry a 20 amp load.
Calculate the size of the circuit breaker needed to safely carry the load. Circuit breakers are most commonly found in 15, 20, and 30 amp sizes. For the load calculated above, 20 amps, the smallest circuit breaker you could install would be a 20 amp breaker. However, following the NEC 80 percent rule, the proper breaker for this application would be calculated as follows: 20 (amps) times 1.25 (125 percent) = 25 (amps). This application requires a 25 amp circuit breaker.
Wire size is a very important part in sizing a circuit. For circuit breakers up to 15 amps, use 14 gauge wire or larger. For a 20 amp breaker, use 12 gauge wire or larger. For up to a 30 amp breaker, use 10 gauge wire or larger. These are the most common sizes for household use.
Wire is manufactured to a specific group of sizes that are designated by numbers known as gauges. The gauge of the wires that carry the power from the transformer to your home and within your home are chosen in size to ensure that they do not overheat at their rated amperage. In fact, there should be no noticeable heat on the wires at any time.
For this reason simply increasing the size of a circuit breaker without also increasing the wire size can lead to a potentially dangerous situation that can result in fire and death.
Choosing the correct wire gauge within your home, wires that run from the electrical distribution panel to various appliances and receptacles is crucial. You do not want the wire to act as a fuse and burn should a short circuit occur.
The table provides the correct gauge of wire for electrical circuits in your home depending on the rated load.
It is also very important not to use devices labeled for copper only on circuits with aluminum wire. Look for these markings on your existing circuit breakers and receptacles and if you have aluminum wiring in your home it is best to hire a licensed electrician to make any alterations to your electrical system.
Low voltage lighting transformers have become commonplace in many of today’s homes with the increase awareness in energy efficient lighting systems and decorative accent lighting. A low voltage lighting transformer is a device that converts the standard 110V or 120V household voltage to a lower voltage such as 24V or 12V. Low voltage transformers can be installed outside in a weatherproof enclosure, or in a basement or garage to power low voltage landscape or deck around the home. The transformer can be hard-wired to the home’s electrical system or plugged in to a receptacle to power the transformer and then a smaller gauge cable distributes 12V to various lighting devices.
The purpose of a low voltage lighting system is to reduce the size of the wiring, increase the number of lights on a circuit, and make installing light fixtures quick and easy for the do it yourselfer and professional alike. Lowering the voltage supplied to the fixtures reduces the chance of injury in the event a wire is damaged, but other problems can occur that can reduce the effectiveness of the light system.
Typical Low Voltage Lighting Circuit
The Lighting System is Completely Off
If the whole lighting system is off the first item to check is that there is power to the transformer. If the transformer is plugged in, make sure that the circuit is not tripped to the receptacle. Transformers installed outside are typically plugged into a GFCI receptacle, so make sure that the receptacle has not tripped. After several years the GFCI receptacle may need to be replaced. Check the electrical panel and verify that the breakers are not tripped or turned off. Use a volt meter to check if there is power to the receptacle or transformer. In some cases the timer has not been set properly, or if there has been a power outage, the time may be off by several hours. Reset the timer inside the transformer and verify that the lights are on.
Fuses, Breakers, and Overloading
Another common problem that may cause an issue is a blown fuse or tripped internal breaker that may be installed in some units. Transformers have a power rating in Watts, such as 600W, 900W, and 1200W. The system may be overloaded with too many lights, or lights that exceed the recommended wattage. Reduce the number of lights and replace the fuse or reset the breaker to restore power to the lighting system. A damaged wire may also cause the breaker to trip. If you have too many lights installed on your system you can installed a new transformer with a higher capacity as long as you do not exceed the amperage of the circuit in your main electrical panel.
Fuse in the bottom of a Lighting Transformer
If there is only one light out, the issue may not be the transformer but a loose bulb or connection. To troubleshoot this problem, verify that the bulb is connected properly in the socket and that the filament is intact. If the light is still out, inspect the wire connecting the light bulb to the main cable and verify that it is not broken. In order to check if the wire is not broken, you may need to use of an ohmmeter. Shut off the power and check if the reading is high or low. The wire is broken if the reading is very high and will require a change in wiring. A string of lights may also be out if there is a break similar to Christmas lights.
Dimmed and Flickering Lights
Dim lights are the result of an overloaded transformer, but not overloaded to the point of tripping the breaker or fuse. To solve this problem a new transformer with a higher capacity needs to be installed since all transformers have a power capacity. Other problems that can lead to dimmed lights are undersized wiring between the transformer and the lighting devices and poorly spliced and terminated wires. The length of the wire is also a factor as very long runs will reduce the voltage to the light and cause it to be dimmer. Review the installation manual for your transformer to determine the proper wire sizes and quantity of lighting devices.
You may be able to install an additional transformer and separate a few of the lighting runs. The problem with this is that the timers will need to be synchronized so that the lights go on at the same time.
Installing a ceiling fan/light combination is a common home improvement project. The part of these projects that confuse many new do-it-yourself persons is how to wire the electrical wiring, so the fan and the light can be controlled by separate, wall-mounted switches. Many handy persons who are ready to tackle any carpentry, painting or plumbing project without any hesitation shy away from tackling electrical projects. There is no reason to pay a professional electrician $50 to $100 an hour when you can do it yourself. After reading this how-to guide, you will know how the fan/light circuit works and will be able to wire your fan/light switches with confidence.
How is the home Cable Run?
In the electrical trades, “home-run” refers to the cable bringing the power from the service panel. Depending on whether the service panel is closer to the ceiling outlet box or the device box that will house the switches, the home-run cable will either enter the ceiling outlet box or the wall-mounted device box. The way you wire the switches will depend on whether the power is brought to the ceiling outlet box or to the device box that will house the switches.
What type of single-pole switch to install
You will install 15-Ampere, 120-volt, single-pole toggle switches, but their physical configuration will depend on whether they are being installed in a single-gang or a double-gang device box. If they are to be installed in a single-gang device box, the device box normally occupied by a single switch, you will need to use a double switch. A double-switch has two switches mounted on a one mounting strap. If you are installing them in a double-gang box, a box designed to hold two switches or two receptacles, you will install two separately mounted switches. For this tutorial's illustrations, I'm using a double-gang device box and two separately mounted switches.
How to wire the switches: With the home-run terminating in the device box holding the switches.
When the power is brought to the switches, a 12/3 w/Gr Romex cable is run from the switches to the ceiling outlet box. The 12/3 w/Gr cable contains three insulated conductors—one red, one black and one white—and one bare copper conductor.
The home-run cable from the circuit breaker panel is brought to the switches when the switch location is closer to the circuit breaker panel than the ceiling outlet box. As a rule, you will run a 12/2 w/Gr Romex cable from the breaker panel to the two-gang device box as the home-run cable. You could run a 14/2 w/Gr Romex cable and protect it with a 15-Ampere breaker, but few professional electricians install anything less than 20-Ampere branch circuits today. It is sound practice to install 12/2 and protect it with a 20-Ampere breaker because you may want to add other loads to the circuit at some time in the future. The home-run cable contains three conductors—one black insulated conductor, one white insulated conductor and one bare copper conductor.
As you see in this diagram, the black wire bringing power to the switches is connected to the bottom brass color screws on the switches by black pigtail wires that are connected to the black circuit wire in a three-way splice.
How to make a pigtail splice
- Making a pigtail splice is a straight forward process. Here, is how to do it like a professional electrician.
- Cut each pigtail wire 6 to 8 inches long. Looking at diagram 1, you will see that you will need two black pigtails and two bare copper pigtail wires.
- Remove ¾ of an inch from each end of the insulated pigtail wires.
- Make an open loop on one end of the pigtail wires, the loop will be used to connect the pigtail wires to the switches.
- Hold the other end of the pigtail wires next to the stripped end of the circuit conductor of the same color and twist tightly together with Electrician's (Lineman's) pliers. Twist them together in a clockwise twist. Remember that every solid electrical connection starts with a solid mechanical connection. Complete the splice by screwing a wire nut on the spliced end.
- Double-check to be sure that no bare copper is showing from beneath the wire nut when splicing an insulated wire. If bare copper wire shows outside the wire nut, remove the wire nut and cut the stripped splice as needed, then replace the wire nut.
Connecting the white, neutral wire
As you will see from diagram 1, the neutral wire from the breaker panel is spliced together with the neutral wire from the light. Splice the two neutral wires together in the same manner as you spliced the pigtail wires to the circuit wires.
Connecting the switches
- Connect the black pigtail wires to the bottom, brass colored screws on the switches. The loops should be placed around the screws in a clockwise direction so that the wire will be pulled tighter under the screws as the screws are tightened down on the wire. Never placed the loops in a counterclockwise direction because the wire will be forced out from under the screws as the screws are tightened.
- Connect the red wire traveling on to the ceiling outlet box to the brass screw on one switch and the black wire going to the ceiling outlet box to the top brass screw on the other switch.
- Attach the bare copper ground pigtails to the green, octagon-shaped screws on the switches.
- Connecting the fan/light unit.
- Connecting the fixture is a straightforward process of splicing the circuit wires to the fan/light unit's fixture wires. Splice black to black, white to white, red to red and bare ground to bare ground.
How to wire the switches: With the home-run terminating in the ceiling outlet box
Wiring the switch-leg
When the home-run cable enters the ceiling outlet box, the 12/3 w/Gr Romex cable running to the switches is referred to as a switch-leg. Normally, the National Electrical Code (NEC) only permits a white, insulated wire to be used as a circuit neutral. There are a few exceptions to that rule. One of those exceptions permits a white, neutral wire to be used a hot wire when it is properly re-identified by painting it or wrapping it with a color tape. In this case, you will see that it has been re-identified by wrapping it with black, plastic electrical tape. We could have used any color tape except white or green tape because white is for a neutral conductor, and green is for a grounding conductor. In a switch-leg, the re-identified neutral is used to carry the power from the black, home-run wire to the switches.
Wiring the switches
Connect the re-identified white, neutral wire to the two, bottom brass screws on the two switches using black pigtail wires. Connect the red and black switch leg wires to the top brass screws on the switches and the bare ground wire pigtails to the two green, octagon-shaped screws.
Wiring the light/fan unit
Connect the home-run neutral wire to the white fixture wire. Connect the home-run bare, copper ground wire in a three-way splice with the fixture ground wire and the switch-leg ground wire. Connect the red and black switch-leg wires to the red and black fixture wires.
Sometimes when a light is not working it isn’t always the bulb.
Some recessed lights use a transformer that is mounted to the light above the ceiling. Low-voltage recessed lights use transformers to convert high-voltage electricity to a low-voltage power supply, usually 120V down to 24V or 12V. Replacement transformers must match the recessed light's old transformer's input and output voltage ratings. Placing standard voltage on a low-voltage light bulb causes its filament to burn up almost instantly.
If you have a remote transformer for low-voltage track lighting or low-voltage halogen lights you need to locate the enclosure where the transformer is installed and replace it with a matching one. These transformers can be susceptible to voltage spikes and surges caused by lightning strikes and power outages.
Always use caution when working with electricity.
1. Turn off the electricity to the recessed light at electrical panel by shutting off the circuit breaker that controls the lights. You may have to shut off the power to the entire room if the lighting is not on a separate circuit.
2. You may be able to access the light's electrical box from the attic, if possible, or from the room. Transformer access from below the ceiling requires removing the trim cover and light bulb and unscrewing the can from its mounting bracket with a screwdriver. Trim covers pull straight down and unsnap from the housing. The housing of the light, called a “can”, screws to a mounting bracket near the bottom, usually with a 1/4-inch hex-head screw. After unscrewing the can, push it up into the ceiling and turn the can until the electrical box can be seen through the hole in the ceiling.
Recessed Lighting Fixture with Transformer Mounted on Electrical Box
3. Open the recessed light's electrical box with a slotted screwdriver. Remove the wire connectors from the old transformer and the electrical wiring. Separate each set of wires. There are two high-voltage and two low-voltage wires. The two low-voltage wires go to the light socket and the two high-voltage wires enter the electrical box from above the ceiling.
4. Unscrew the transformer's mounting screws with a screwdriver or 1/4-inch nut driver. Remove the old transformer from the electrical box.
5. You may need to take the transformer to a home center or electrical supply house to match the ratings. They are common so there are usually in stock. The label on the transformer lists the ratings and shows the wiring guide. Pay special attention to the primary and secondary voltage ratings and the wattage. For track lighting systems you can overload undersized transformers if higher wattage bulbs are installed in the fixtures.
6. Note the new transformer's wiring guide. The wiring guide lists each wire, its insulation color and its function. Usually there is a black and white wire for the primary coil that is connected to the black and white wiring from the house. The low-voltage wires are red, blue, or yellow and are connected to the low-voltage wires going to the light.
7. Attach the new transformer to the recessed can light's electrical box with the screws that held the old transformer.
8. Connect the high-voltage wires from the transformer, labeled “Primary,” to the high-voltage wires that enter the box from above the ceiling and secure them with wire nuts. Often the transformer uses black and white colored insulation for the high-voltage wires. If so, then connect black to black and white to white. Otherwise, connect the transformer wire labeled "Hot" to the black wire and the transformer wire labeled "Neutral" or "Common" to the white wire.
9. Twist the transformer's low-voltage, labeled "Secondary," wires to the low-voltage wires that connect to the light socket and secure them with wire nuts. Many transformer manufacturers use blue and yellow insulation for the secondary wires. The low-voltage wires can be connected either way and do not have to be matched to the wires going to the light.
10. Replace the electrical box's cover. Screw the can to its mounting bracket, replace the light bulb and trim piece.
Note: Transformers may or may not have a green ground wire depending on the manufacturer.
One of the few appliances in the kitchen that is wired directly to a dedicated circuit is the dishwasher. Aside from the heating element which draws a considerable amount of amperage, the dishwasher is connected to a water source which can pose an elevated risk to shock and circuit overload. Having other items connected to the same circuit can cause the breaker to trip.
As long as the circuit breaker is turned off the connection can be made fairly easily. If you are not comfortable with making the electrical connections for the dishwasher, you should hire a licensed electrician to install the appliance on the dedicated circuit.
Tools and Materials
This article goes over the electrical connections for the dishwasher and does not focus on the plumbing connections such as the water supply hook-up and drain hose. Make sure to shut off the water supply to the dishwasher before attempting any electrical work on the dishwasher or circuit.
The electrical connection for the dishwasher is usually on the wall behind the dishwasher opening, in the cabinet under the sink, or sometimes there will just be a wire sticking out of the floor or wall.
Electrical cable (white wire with yellow wire nuts) and no junction box
1. Turn Off the Power
Locate the breaker for the dishwasher and turn it to the OFF position. If there is a junction box installed, remove the cover plate and test the black wire to ground to determine that the power is off. Use a voltage tester to test the wires to make sure the circuit is off before you start working.
2. Preparing the wires
If you have an old dishwasher you are replacing, you should be able to use the existing wire. Inspect the cable sheathing and wiring to make sure that there are no tears, crimps, or scorch marks present. If there is any damage to the cable, cut it back to a good section and install a junction box on the wall. Cut a new of cable (12-2 gauge) about 4 feet long to feed the dishwasher from the junction box. Use a utility knife to remove the last 6-inches of sheathing from the cable to expose the wires. You may want to tape the end of the wire to the floor since the electrical connection is made in the front of the appliance.
Damaged wiring at the cable connector
Strip about ¾-inch of insulation from the ends of the white and black wires.
When the ends of both wires have been stripped, slide the cable connector over the end of the cable and secure it in place over the sheathed portion of the cable with the threaded end facing outward. Remove the locknut from the threaded end of the connector.
3. Secure the Cable
If you have installed a junction box you need to remove two knockouts; one for the cable coming from the panelboard and one for the cable going to the dishwasher. To remove the knockouts, hit the edge with a flat screwdriver or a pair of needle-nose pliers then grab the knockout with the pliers and twist it until it breaks free.
Take the wires and guide them into the box until the cable connector’s threads are on the inside of the box. Slide the locknut over the wires and secure the connector to the box.
4. Complete the Wiring
- Take the ground wire and secure it to the green ground screw on the dishwasher and tighten the screw.
- Make the connections for the black wire from the circuit and the black wire from the dishwasher twisting the wires together with pliers and capping them with a wire nut. Repeat this for the wire wires.
3. Wrap each wire nut with electrical tape.
4. Carefully bend the wires so they fit inside the dishwasher junction box and replace the cover plate.
5. Complete the water line hook-up and drain hose to the dishwasher. Check for leaks after turning on the water
6. Carefully push the dishwasher into the opening and secure it to the countertop with the screws supplied with the dishwasher.
7. Level the dishwasher by adjusting the feet in front with an adjustable wrench and 2-foot level.
8. Test the dishwasher operation.
Many times people would like to have an outlet controlled by a switch to be able to turn on a lamp or some other device. Sometimes they have a switched outlet, but it is in the wrong location, or they would like to plug in another device that they would like to remain on all the time. A situation like this calls for a half hot outlet where a switch controls the top half of the outlet and the bottom remains hot all of the time.
As always when working on electrical systems turn off the power to the circuit at the breaker panel or remove the fuse for older electrical systems.
If you have an outlet that is switched, you will still need to run a new wire with two hot conductors and one neutral and one ground, 12-3 or 14-3 wire. The “3” stands for 3 conductors, black, red, and white. The red wire is required to keep one half of the outlet hot at all times.
Traditionally the black wire is used for the hot portion of the outlet and the red wire for the switched portion, but it will work either way. The outlet will share the neutral, white wire, in this case.
Half-Hot outlet Wiring Diagram
To run the new wire you will need to either cut a few access holes in the wall board new the studs to run the wire from the switch to the outlet. I you are lucky it will only require two of three small holes to get your hand inside. Cut the holes to straddle the stud, you can use the switch box and outlet box for the beginning and ending holes. If you have access from the basement, you can run the wire straight down, staple it to the floor joist, and then drill a hole up into the stud bay of the outlet. Make sure that you have the location marked accurately.
1. With the power off to the circuit, remove the switch and outlet from the wall boxes.
2. Remove the wire nuts off of the wires. Strip the insulation from the insulated wires according to the strip gauge on the back of the outlet. Use you wire strippers or pliers to make a hook on the end of the ground wire so it can be attached to the ground screw of the outlet.
3. There is a tab that joins the upper and lower sections of the power side of the outlet together. This is a flat brass piece of metal; the hot side of the outlet is the side with brass colored screws. Leave the other side intact.
4. By using a pair of needle nose pliers you can grip the flat tab of metal and with a side to side motion bend it until it breaks off.
5. Connect the red half of the outlet you want controlled by the switch and the black for the half of the outlet which is hot all the time. (Typically the top is the switched part of the outlet) It is best to use the side screw terminals to make the wiring connections. The white wire is connected to the white (aluminum) screw on the other side. The tab remains in place to share the neutral connection. I like to use electrical tape to wrap the outlet and cover the screw terminals for the hot and neutral.
Red and Black wires in place.
6. At the switch, the white wires are connected together with a wire nut.
a. The black wire coming into the switch is normally hot; connect it to the top of the switch with the new black wire going to the hot part of the outlet.
b. Connect the red wire to the bottom terminal of the switch that is connected to the switched portion of the outlet.
c. Connect the bare or green ground wires to the ground terminal screw on the switch.
7. The wiring is folded back into the outlet box being careful that the ground wire is not near the screws of the outlet's hot or neutral side.
8. Use the outlet mounting screws to secure the outlet firmly to the wall adjusting the outlet from side to side as necessary and replace the outlet cover.
9. Turn on the power to the circuit and test the operation by plugging in a lamp and radio into the switched and hot portions of the outlet.
While this job may not add much value to your home, it will offer you great flexibility and convenience for the rooms you choose to make this electrical modification. Check with your local building inspector to determine if you require a permit before you start the work.
A circuit breaker that trips open intermittently may be indicative of a circuit overload or an intermittent short circuits. Two reasons a circuit breaker trips open are circuit overloads and short circuits. Circuit breakers, like the older, Edison-based fuses, are designed to protect electrical writing against circuit overloads and short circuits.
Short circuits occur when a hot wire comes into contact with the circuit's neutral conductors or when it comes into contact with some grounded surface. Short circuits are relatively easy to diagnose because the circuit breaker will not hold after resetting until the short circuit is located and repaired. Circuit overloads, on the other hand, are not so easy to diagnose because, depending on the amount of the overload current, the circuit may hold after being reset until the heat building up from the overload current causes the thermally operated circuit breaker to trip open once again.
A third possible cause for a circuit breaker to trip open is that the circuit breaker itself has become defective. Circuit breakers becoming defective is not a common problem with residential wiring systems, but it can happen. There might have been a manufacturing defect with the circuit breaker that the QC inspections did not catch. This kind of problem usually makes itself known relatively soon after the CB is newly installed. Another cause for a CB to become defective is a power surge that causes so much heat in such a short period of time that the bi-metal strip in the CB is weakened or damaged in some other way.
How much circuit current constitutes a circuit overload?
Residential 120-volt branch circuits are either protected by circuit breakers rated at 15-amperes or 20-amperes but that does not mean that these circuits can be loaded down at constant 15 or 20-amperes current. The reason for that is that most circuit breakers are designed to only carry a continuous current of up to 80 percent of their rated current. In other words, a circuit protected by a 15-ampere CB has a load rating of 1,440-Watts or 12-Amperes.
A circuit protected by a 20-Ampere CB should be loaded to 1,920-Watts or 16-Amperes. These maximum safe loads are not only required by the CB's design, they are requirements of the National Electric Code (NEC). There is one exception to this rule, some circuit breakers are designed to carry 100-percent of their rated current and those CB's are so marked on their cases.
Troubleshooting and Isolating circuit overloads
If you do not already own a clamping ammeter, now is the time to procure. There are many quality clamping meters on the market today at very reasonable prices but one of the best sources of tools for the do-it-yourself person is Harbor Freight. You could spend hundreds of dollars for a clamping meter but the Cen-Tech 7—Function, clamp—on multimeter sold by Harbor Freight for less than $30 will be all the meter the average do-it-yourself person will ever need for residential electrical work. This meter tests resistance and AC and DC voltage without splicing wires or puncturing insulation. The meters 17-test ranges include
- DC Voltage—4 ranges 200mV/20V/200V/1000V
- AC CurrentAC Voltage—2 ranges 200V/750V—3 ranges 20A/200A/1000A
- Resistance—5 Ranges 200Ω/2kΩ/20kΩ/200kΩ/2MΩ
- Diode Test
- And a Continuity Test.
The actual product/operating manual is available in pdf format here.
One of the very first rules that every do-it-yourself person is taught when doing an electrical project is to always turn the electricity off first by switching the circuit breaker to the off position. But, as James Thurber (1894-1961), the writer and cartoonist once said, “There is no exception to the rule that every rule has an exception.” This is one of those exceptions for electrical safety rules. When performing an electrical circuit load test, just as when performing circuit voltage tests, the power must be left on.
Performing the load test
Ido not believe in reinventing the wheel. I have already published a step by step guide called “How to Tell If You Have a Faulty Breaker in Your Breaker Box” on e-How.
If the circuit is actually overloaded, the meter indicates a load of more than 12-Amperes on a 15-Ampere circuit or a 16-Ampere load on a 20-Ampere circuit, you will need to reduce the load by moving some of the plugged in loadsto a different branch circuit.
Replacing a defective circuit breaker
If the load current is 80 percent or less of the circuit breaker rated amperes and the breaker continues to trip open, you will need to replace the circuit breaker. For a good step-by-step guide for removing and replacing a defective branch circuit CB, go to Replacing a Breaker in Your Panel.
One of the most frustrating things about fishing wire through the walls of older homes is encountering unexpected obstructions. Older homes often have one or more 2 X 4's running horizontally between studs as fire stops. Running wire through such a wall space is very time consuming and labor intensive. First, you have to locate each of those horizontal blocks.
Next you have to remove a section of the wall finish in front of each of those blocks, large enough to allow you to drill through the block or to notch the block for the cable to pass through it. Then, after getting the cable where you need it, you have to go back and patch all the holes you made in the wall. Having to patch a hole/cutout in a modern wall with a wallboard finish may not be all that bad, but you have quite a job on your hands if you are working on an older home that has plaster wall laid over wooden lath. Running the wire behind baseboards and around door casing takes a fraction of the time while causing little damage to the wall finish.
Tools and supplies needed for this project
5 in 1 Tool
Flat Pry Bar/Stanley Bar
4” Putty Knife
Scrap Piece of Plywood
Portable Electric Jigsaw
1-Inch Wood Chisel
24-Inch Carpenter's Level
Carpenter's Pencil or Felt Tip Marker
Removing the Baseboard
Proceed carefully here, especially when working on older homes, because wood dries out with time and it is very easy to crack a baseboard or door casing during removal. Finding an exact replacement molding may be impossible and will end up a custom molding milled to order and that can get expensive. If you follow these steps and work slowly, you should not have any problems.
Using your utility knife, carefully cut the caulking and/or paint bead between the top of the baseboard and the wall. If you neglect to cut through the bead first, you damage the wall when prying off the baseboard. With wallboard, the paper facing is easily ripped if the bead is not broken. With older, plastered walls, large chunks of the plaster is likely to come off with the baseboard if you skip this step.
Once you have cut through the bead, carefully drive the 5-in-1 tool down behind the baseboard.
Your objective here is to create enough space between the baseboard and the wall to insert your Stanley Bar.
Place the plywood scrap between the Stanley Bar and the wall to keep from damaging the wall as you pry the baseboard away from it. Work you way slowly along the length of the baseboard, prying it away from the wall a little at a time. Trying to pry too much at one time will end up with you breaking the baseboard. Follow these same steps when removing a door casing.
Once you have removed the baseboard, cut a channel in the wall finish. Since “Nailing Plates” are 1 and ½ inches by 5 inches, you need to cut a channel in the wall behind the baseboard at least 5 inches in width.
Outline the area to be cutout using your level and felt tip marker. Then drill 3/8-inch holes in each corner of the cutout so you can insert the blade of your portable electric jig saw.
Set the depth of cut for 1 and ½ inches so you will cut through the wall finish but not the wall studs at the same time. Once you have made the channel, cut a 3-inch long X 1-inch deep notch in the studs using the jigsaw and the 1-inch wood chisel and hammer.
Once you have the cable in place, cover the notches with the steel nailing plates.
Running cable around doors behind the door casing
Once you have removed the door casing there will be a space already available for you to lay the cable in.
Reinstalling the baseboard
When reinstalling the baseboard, you will need to shim it out at the studs using wood the same thickness as the wall finish, which is usually 1/2-inch if you have wallboard. It is also a good idea to run a strip along the front of the wall's sill plate too for extra support.
At some point you may want to have power in a garden shed or detached patio or some other area in your yard. Instead of running an extension cord to that particular location you may want to install an underground conduit or direct burial electrical cable to provide a more permanent solution. Consult your local building department concerning electrical regulations before attempting any underground installation. Some local agencies may require a permit to be issued before any trench is dug and you may want to have a survey done of your property to locate any exiting underground electrical, water, and gas lines. Most states have a Call Before You Dig hotline or you can contact the service department for your local utility company for assistance.
Direct Burial Cable Installation
This is a more simple approach as special electrical cable can be placed directly in the ground. Consult your local building inspections department to determine if this type of installation is allowed and acquire the appropriate permits.
This article does not describe how to terminate either end of the cable at the circuit breaker or outside receptacle or structure.
Supplies and Tools
Marker flags or landscaping spray paint
Type UF (underground feeder) wire
1. Lay out the route of the cable run with marker flags or paint to indicate the beginning and end of the underground trench location. If the trench is not a straight line, a marker flag should be placed at every deviation or turn from the straight line.
2. Use a shovel to dig the trench. Keep in mind that the type of underground wires and voltages will play a key role as to the depth of the trench. The National Electric Code (NEC) Table 300-5 is used to determine the overall depth of the trench. In residential installations the underground cable is carrying less than 300 volts. This would require a minimum depth of 12 inches of soil covering the wire or cable. Branch circuits rated 20 amps or less with GFCI protection at their source are allowed a minimum cover of 12”.
Cables that are carrying irrigation circuits and landscape lighting voltages of 30 volts or less, will need a trench of no less than 6 inches deep.
3. Remove all loose soil and rocks from the underground electrical cable or wire trench.
4. Lay the underground feed wire, Type UF, into the trench. Some regulatory agencies may require an inspection after the wire is laid into the trench, but before any soil is placed back into the trench. Obtain the proper inspection.
5. Backfill the trench soil that is free of any rocks. Do not place any type of rocks back into the trench, as the hard edges can and will damage the wire's outer insulation over time.
You may also want to install plastic caution tape about 6 inches above the cable and then fill in the remaining 6 inches of soil on top of the tape.
Various Underground Warning Tapes
Today, you have an alternative with rigid polyvinyl chloride (PVC) conduit. The National Electrical Code (NEC) permits you to use this conduit for direct burial installations.
Before beginning this project, you need to determine the size of the subpanel that you plan to install in your shop. The loads the project will serve will determine the size of the underground service---the size of the individual conductors and wires---which in turn will determine the size of the conduit that you will need to run.
Additional Tools and Supplies
PVC 90 degree elbows
PVC Threaded fittings for receptacle box, if needed
Electrician’s Fish tape
1. For installing conduit you will want to keep the run as straight as possible. Typically you can only pull wire through four 90 degree bends, including the ones that turn up out of the ground and into the panel. If you have more than 4, you will have to install a hand pull box in the ground to allow you to pull the wires to this point and then feed them back into the conduit and continue to the end of the run.
2. Dig the trench 24 inches deep. Table 300-5 of the NEC requires that nonmetallic conduit be buried at least 18 inches below the surface. Depending on the length of the trench you are digging and the type of soil that you have, you may want to consider renting trenching machine.
3. Begin laying the conduit where the connection to the panel will be. You will need to core a hole into the basement wall or wood sheathing to do this. You can install an elbow and come out of the ground to allow you to enter the home through the wall instead of the foundation.
Sweep in Trench
4. Lay out the conduit end-to-end next to the trench. Cut the final length so that the last elbow is positioned correctly. Using a PVC cutter assures you will have a square cut, but you can also use a hacksaw to cut the conduit.
5. You can purchase conduit that have a flared female end on one end of the pipe so that you will not need couplings. If you have straight conduit assemble the conduit lengths using couplings. Prime the facing ends of the conduit and conduit couplings. Prime the inside surface of the coupling and the outside surface of the conduit to the depth of the coupling. Immediately coat the inside surface of the coupling and the outside surface of the conduit with the PVC cement and force the coupling and conduit together, giving them a quarter-turn twist to distribute the cement evenly around the joint. Repeat until all the conduit lengths are joined together.
6. Install the 90 degree sweep elbow at the end of the run and a piece of conduit to bring the conduit to the proper finished height.
90 degree Sweep
7. Wait 30 minutes for the joints to set up before pulling the wiring through the conduit. Feed the fish tape from the access on the outside of the house to the end of the run.
8. Remove 6 inches of insulation from the ends of the insulated wires. Loop the stripped ends through the eye on the fish tape, wrapping the stripped ends around the wires coming from the spools. Tape them in place. Note: You can run UF cable in the conduit, but it is difficult to pull through due to the outer layer of insulation.
9. Pull enough wire through the conduit to reach through the wall and the inside conduit to the shop's subpanel.
10. Cut the wires long enough on the house end to pass though the wall and inside conduit to the service panel.
11. Seal around where the conduit passes through the walls using spray foam insulation or caulking.