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Could I just throw away my old recyclable batteries?

No, laws require that they be recycled. This includes Nickel Cadmium (Ni-Cd), Nickel Metal Hydride (Ni-MH), Lithium Ion (Li-ion) and small sealed Lead (Pb) batteries. You can look for a battery recycling seal on the rechargeable batteries found in cordless power tools, cellular and cordless telephones, laptop computers and camcorders.

What is a time delay fuse?

Time delay fuses are used on circuits where appliance motors have initial surges of electrical power when the motor starts. This initial surge might blow a regular fuse.

I need a circuit breaker, but I don't have it with me. Are they all the same?

No, it's best if you bring in the old breaker and match it up. If you know the name of the brand of service box, we could also match it that way.

I have a circuit breaker that tripped. Is this dangerous?

Usually the problem is simply an overload and you only need to run fewer appliances on the circuit. However, if it is not overloaded and it keeps tripping, you should suspect a short. Also, look for a defective cord, socket or plug.

Is it all right to replace a fuse or circuit breaker with a larger one to prevent them from blowing or tripping?

In most cases the answer is no. They are designed to blow at certain levels to protect equipment and for fire safety.

What is the difference between a floodlight and a spotlight?

The floodlight will have a broader light pattern, while a spotlight will focus on a more narrow area.

Do 4-foot fluorescent fixtures come in different wattages?

Yes, the most common are 25-, 34- and 40-watt bulbs.

What is the advantage of a halogen bulb?

It provides brighter, cleaner light. However, it consumes lots of electricity and gets very hot. You should ensure that it stays away from draperies, bedding, clothing and hanging plants.

Do I need to buy a special bulb for my garage door opener?

It's best to use a rough service bulb.

What's making the tubes in my fluorescent light flicker?

Wiggle the tubes to make sure they are properly seated. Replace any tubes that are dark or have damaged pins. Replace the starter if there is one.

The dryer plug will not fit the receptacle in our new house. How can I remedy this?

In most new homes, there should be four-prong dryer and range receptacles. If you have a three-prong power cord, you will need to change it.

What is a polarized plug?

One prong is bigger than the other. This feature is designed to make sure that a 110-volt plug is never put into a socket that is not a 110-volt outlet.

Will a three-pronged plug adapter protect me against electrical shock when I use it in a two-prong receptacle?

Only if the wall plate screw is grounded.

What do I need to buy for a basic electrical tool kit?

We recommend the following:

  • Needle-nose pliers
  • Insulated screwdriver
  • Combination tool
  • Utility knife
  • Keyhole saw
  • Continuity tester
  • Neon circuit tester
  • Fish tape
  • Electrical tape
  • Wire connectors

How do I test a switch to see if it is working?

I recommend using a continuity tester. First, shut off the electricity going to the switch and remove it. Touch the tester leads to both of the switch's terminals. If the switch is working properly, the tester will light up when the switch is on and go out when the switch is turned off.

What type of switches will I need to turn a light on from two different locations?

You will need a three-way switch at each location. A three-way switch will have three terminal screws on it.

What is the easiest way to test an outlet?

Use a receptacle analyzer. Leave the power on, but make sure nothing is plugged into any outlet on the circuit, and turn off all switches on the circuit. Now, plug the analyzer into the outlet. A series of lights will tell you if the outlet is wired correctly and working.

My extension cords are always getting tangled. Is there anything I can use to store them?

There are a variety of cord storage reels available.

What do numbers on electrical cable mean?

They refer to the number and types of wire inside the cable. For example, 14-2 means the cable has two 14-gauge wires inside. 12-3 G means the cable has three 12-gauge wires plus a bare ground wire.

How large of a cord should I use when wiring an appliance?

Use cords with 16-gauge wire for appliances pulling less than 15 amps and 12-gauge wire for appliances pulling up to 20 amps.

What do the colors of the plastic insulation mean on wires?

They are designed to indicate their use, but be careful because they are not always hooked correctly. Hot wires, those carrying current at full voltage, are usually black, red or white with black marks. Neutral wires are usually white or gray. Ground wires are usually either green or bare copper.

I am installing a ceiling fan; do I need a special electrical box?

Yes, special saddle boxes are designed for hanging heavy fixtures-up to about 50 pounds. Since a ceiling fan moves, these boxes are good for about a 35-pound ceiling fan.

When my house was built, they did not install a doorbell. Is there an easy way to solve this?

Yes, there are wireless door chimes.

What is a ground fault interrupter?

It's a safety device that shuts off the power if a wire in an outlet develops a leak that could electrocute someone. This hazard is so serious that the National Electrical Code requires all new homes be equipped with them in the bathroom, kitchen, workroom, outdoor, basement, garage and swimming pool circuits.

What is a transformer?

It's a device that changes the voltage. In most home usage, it reduces the voltage for use on low-voltage equipment, such as thermostats, doorbells and low-voltage outdoor lighting.

If there is a short in the line, where should I look for it?

Search for loose taped wire; also look for worn fabric insulation on old wires and check any terminals that have multiple wires since one of the wires may have slipped off.

How do you figure amperage?

It's watts divided by volts. For example, a 1500-watt heater (divided by) 120 volts equals 12.5 amps.

What is Underwriters Laboratories?

It is a non-profit organization that tests and approves electrical products. Look for "UL" labels of approval to help ensure appliances are safe.

My doorbell doesn't work, do you know what's wrong with it?

There are three components to the doorbell; the button, the transformer and the bell itself. First, look for any loose wires throughout the system. If all the wires are connected, test the doorbell button by removing it and touching the two wires together. If this makes the doorbell work, you have a bad button that is easily replaced.

I've bypassed the doorbell button, and the doorbell still did not work. What's the most likely problem?

Check the transformer. You will have to find it. It might be in the attic, but it can be anywhere. You just need to trace the wire. If it makes a humming sound when the button is pushed, your problem is probably the chime. If it doesn't make a sound, change the transformer to see if that's the problem.

Do all of the outlets in my kitchen need to have ground-fault circuit interrupters?

No, if the first in the series is GFCI, then all are protected.

Is there a light switch that I can use to replace one in my house?

Yes, but is it a single pole or is it a three-way switch. A three-way switch is one that is used when a light is controlled by more than one switch.

What does gauge mean?

Wires have size numbers that express their diameter. These are even numbers from 0 to 18, and smaller numbers indicate larger diameters that can carry more power.

I am putting a couple of more outlets in my garage. Can I use 14-gauge wire?

While 14-gauge wire is the minimum for most house wiring, it can only be used for 15-amp circuits. Number 12-gauge wire is recommended for general home use. There is often a chart on boxes of wire that will show you recommended gauges for specific applications.

I am running an underground cable in my lawn. What should I use to connect the wires?

You can use waterproof wire nuts if you do not have a waterproof box.

I need to install a receptacle for my kitchen range. Is it okay to use one designed for a dryer?

No, they may look similar, but they have different features. Make sure you check the manufacturers' label to ensure you are buying one that is rated for the proper amperage.

Do I need a special lamp for this droplight?

Use a rough service bulb. These heavy-duty bulbs will take rougher treatment and water droplets.

I have a water pipe in an unheated garage. How can I protect it from freezing?

Wrap the pipe with heat tape, which comes in different lengths.

How is UF electric wire different from regular Romax cable?

If you lay cable underground, it must be UF (underground feed) cable, which has each individual wire insulated and has plastic wound around the insulated wire for weather and sunlight protection. Romax has a paper product around the wires.

What type of wire should I use for a 220-volt outlet?

The best choice is a three-wire cable with a ground. Also, make sure it's rated for the amperage you need.

What type of switches will I need to turn a light on from three different locations?

Two of the locations will use a three-way switch and the other location will need a four-way switch.

How do I troubleshoot a fluorescent fixture that doesn't light?

It's probably not the bulb because they rarely go bad all at once. Wiggle the tube to make sure it is seated. Replace any damaged lamp holders. Replace the starter. Check the switch and outlet box to make sure it is getting power.

What's causing my fluorescent fixture is hum?

The ballast probably needs to be replaced. Another sign of a faulty ballast is black tar-like substance oozing from the fixture.

How do I know the size ballast I need for a fluorescent fixture?

You need to know how many bulbs there are and how long they are. However, make sure you check the starter before you change the ballast. In fact, you may want to replace the whole fixture.

How do I check the starter in the fluorescent fixture?

Older, delayed-start fluorescent lights flicker when they first light up. If this lasts more than a couple of seconds, make sure the starter is seated by pushing it in and turning clockwise. If the ends of the tube light up and the middle does not, the starter is bad. Remove it by turning counterclockwise.

The tubes in my fluorescent light are graying near the ends. Does this mean they are wearing out?

Working tubes usually have a gray tinge on the ends, but dark gray or black is a sign that the tube is failing.

My fluorescent fixture does not seem to be putting out as much light as it used to. Could the tube be failing?

If the entire tube is dim, it may simply need washing. Try removing it and wiping it with a damp cloth.

Which color of wire nut do I need?

Check the package. It will tell you what size and how many wires each color of nut will hold.

Is there a special extension cord for my window air conditioner?

Yes, you need to use a major appliance cord. A regular extension cord doesn't have heavy enough wire to safely conduct the necessary current.

Is there a special receptacle I should install outside?

Yes, there is a special box with a cover designed to protect. In addition, the receptacle should also have ground-fault circuit-interrupt protection.

What is the difference between an extension cord rated for outdoor use and a standard one?

The outer coating of the insulation on the outdoor-use cord is weather and sunlight resistant.

Why are electric heaters limited to 1,500 watts?

Because anything over that would exceed the safe amp rating of most wiring and would present a fire hazard.

What tool should I use to strip the plastic sheathing off wire?

A combination tool has openings that fit different sizes of wire. When a wire is put into the correct one and pulled, it will remove the covering without damaging the wire.

Is there a tool for removing the outer sheathing on cables such as Romax?

A utility knife will work, but an inexpensive cable ripper is designed for the task and will not damage the wires inside.

How do I use a wire nut?

Strip off about 1/2" of insulation from the wires you want to connect. Hold these wires next to each other and twist clockwise. Screw on the wire connector using only your hand strength. Make sure no bare wire is exposed.

I need to run some wire through my wall. Do you have any suggestions?

Instead of trying to feed the wire through, use a fish tape. This tool is a small wire on a reel that is easier to feed through. Once you have fed it through the wall, attach the wire and pull the tape back through.

I have some slots left on my circuit breaker box that do not have breakers in them. Can I add more circuits?

You need to see how many amps your box is rated for and then look at the existing circuits to see how many total amps are already being used. If you have not reached the maximum, it's possible to add more, but it's best to have a professional do the work inside the box unless you have the specific knowledge.

How do I connect a wire to the terminal on my light switch?

Bend a stripped wire 180 degrees by bending it over the tip of needle-nose pliers. Wrap the wire clockwise around the screw so that it will stay in place as you tighten the screw. Don't over tighten and make sure there is no insulation under the terminal.

I think there is a short in a wire running to one of my rooms. Is there some way to test it to find out?

A continuity tester will let you know if there is a short. It is a tool that includes a battery so that it can supply a low-voltage current to devices and wires to see if there is a complete circuit.

I have low-voltage outdoor lighting. Can I add additional lights?

You will have to look at your transformer to determine what its maximum wattage is. Most bulbs are 4 watts, but they come in different wattages. You will have to add up what you are currently using.

My dusk to dawn light doesn't go off and remains on all day. Do I need to replace it?

First find the sensor and see if it is being obscured by something. If not, you can probably just replace this sensor.

Is replacing my thermostat an easy project?

Yes, simply remove the old thermostat from the wall. Next, disconnect each wire and mark it so you can keep track of where it was connected. Attach the new thermostat to the wall and attach the old wires.

I want to run a new wire to install some additional outlets. Do I have to run these wires through the wall?

You can use surface wire channels that allow you to run the wire on the outside of the wall and still maintain an attractive appearance.

What is a voltage tester?

It's an inexpensive tool that tests for live current. It can save your life. To use a voltage tester, simply plug its leads into a receptacle, or, if the cover plate is off, touch them to the screw terminals of the device. If current is present, the tester will light.

I have some tools that have three prongs, but the outlet I want to use has only two prongs. Can I safely cut the extra prong off?

No, the third prong is the grounding prong. If you cut it off or use a plug adapter that is not grounded, you will disable a feature that is designed to protect against electrical shock.

Why do some appliances and tools only have two prongs and no grounding prong?

These products are "double-insulated" and do not need the added protection of a grounding plug. You can plug them into ungrounded outlets and still be protected. I've noticed that some outlets have a T-shaped neutral slot. What does this do? It identifies the outlet as a 20-amp grounded receptacle and it should be used only on 20 amp circuits.

What is BX cable?

This is a trade name for an armored cable that wraps the wires in a flexible metal sheathing.

Is it easy to replace a faulty plug?

Yes, start by snipping off the original plug. Slide the cord into the new plug, strip the wires and connect them to the proper terminals. For lamps and small appliances there are quick-connect plugs. The snipped wire is inserted and a small lever is closed, which holds and pierces the wire to make the connection.

Can I add additional outlets to an existing circuit?

You need to figure the current circuit load in watts to see if it can handle additional use. The National Electric Code is 20 percent less than maximum. This means a 15-amp circuit has a safe capacity of 1,440 watts. A 20-amp circuit limit is 1,920 watts, a 25-amp circuit's limit is 2,400 watts and a 30-amp circuit has a safe limit of 2,880 watts.

How can you recognize a socket used for a three-way lamp?

This socket will have a regular contact tab inside, which all sockets have, plus another raised contact point.

Is there a nightlight that will come on automatically when it gets dark for use in my bathroom?

Yes, it's called a photoelectric nightlight.

I know there are fluorescent plant lights that stimulate plant growth, but do they make these bulbs for standard lamps?

Yes, there are incandescent models that screw in.

I am going on vacation. Are there any easy-to-use products that will turn my lights on and off so it looks as if the house is occupied?

Yes, there are a variety of timers that simply plug in.

Do you have something I can use to insulate and repair cords and wire with?

You can use heat-shrink tubing. It's designed to fit something half its size in diameter.

Is it okay to use an extension cord with a fuse on it rather than a surge protector for my computer?

No, a surge protector has components that trip before a spike in electricity damages your electronic equipment.

Do I need special tape for wiring?

Yes, you should use electrical tape.

How much energy do compact fluorescent light bulbs save?

Most estimates are 70 percent, which means that over the life of the bulb you can save as much as $100.

Adding New Wiring From a Junction Box

  • New wiring can also be tied into a junction box, unless the wiring in the junction box is already at maximum capacity.
  • Before tying in at a junction box, always trace the cables leading to the box to check the voltage. Be sure you are not connecting a 120-volt outlet to a run of wire providing 240 volts for larger appliances.
  • To tie in new wiring at a junction box, first shut off the current at the service panel.
  • Locate the main supply cable coming into the junction box from the service panel. Locate the supply wire by tracing the white wires. All white wires in the junction box will be attached to the white wire on the supply line.
  • Knock out the unused plug on the junction box and run the new line from the box as illustrated (see image). Be sure to use a cable clamp to secure the cable to the junction box.

The Single-Pole Toggle Switch

  • The simplest switch system-the single-pole toggle switch is illustrated here.
  • The ordinary single-pole toggle switch provides a means for breaking or feeding electrical current to a light, appliance, etc.
  • The single-pole toggle switch has two brass terminal screws. One wire (usually the black) is cut, then is connected to the two brass terminals.
  • The other wire (white) is uninterrupted from the power source to the light or fixture.
  • When connecting a wire to the terminal screw of a switch, always turn the loop on the end of the wire in the same direction as the screw threads, as shown in illustration A. If the loop is turned in the opposite direction (B), tightening the screw will loosen the loop.
  • If the wire connects to the terminal screw and then runs on, cut and strip the wire on both sides of the cut. Using a 6" piece of wire with both ends stripped-sometimes called a pigtail-and a wirenut, fasten the three wires together. Connect the pigtail to the terminal.
  • Use wirenuts or screw-on connectors to save time and effort when you must make a splice in any electrical wire.
  • Always cover any soldered connection with insulating tape. If soldered sections are rough, apply an extra layer of tape. Insulate the wire an additional inch or two beyond the soldered connection in each direction.
  • White wires should generally be attached to light-colored terminal screws such as silver. Black wires should generally be attached to dark-colored screws such as brass colored. If the terminal screws are the same color, either wire can generally be attached to either terminal. Green terminal screws are for grounding wires.

For additional information on these and other electrical questions, check out these helpful links:

Installing Ceiling FansInstalling Doorbells
Installing or Replacing Electric SwitchesInstalling a Garage Door Opener
Installing Outdoor Wiring/LightingBasic Soldering
Adding Electric WiringInstalling Wall or Ceiling Fixtures

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Check your state and local codes before starting any project. Follow all safety precautions. Information in this document has been furnished by the North American Retail Hardware Association (NRHA) and associated contributors. Every effort has been made to ensure accuracy and safety. Neither NRHA, any contributor nor the retailer can be held responsible for damages or injuries resulting from the use of the information in this document.

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