What is Voltage?

There are a lot of terms associated with electricity. Different words refer to a current’s strength, the speed at which it travels, and the rate at which it’s consumed. Voltage is a sometimes-misunderstood term that means “electomotive force” or, more simply, electrical “pressure.” Voltage also is the difference in electrical potential between one end of a circuit and the other. In our electrical systems, voltage is measured against the earth, which is at zero potential. In other words, it all starts with the ground under your feet. Voltage gets the electrical ball rolling by giving a push to electric power from your utility’s generator to your house or business.
Long-distance power lines carry huge voltages, from around 155,000 to 765,000 volts. If you hooked your vacuum cleaner up to that kind of power, you’d melt its engine instantly—and possibly yourself as well. You previously read that transformers reduce the voltage before it enters your house. A few hundred thousand volts might sound like fun to your kids, but you should be grateful that you end up with a lot less voltage, thanks to transformers.

What is Grounding?

Now that you know what kind of current you have in your house (and everywhere else), let’s discuss another critical feature—grounding. Your entire electrical system, if it’s up to current code, is grounded for your protection. This literally means that one wire of your electrical system leads back into the earth itself, where it will carry any errant current that could otherwise shock or electrocute you. The earth ends up being a good electrical conductor and a convenient return path for electrons. In fact, the earth is used as a reference point for measuring the voltage in our electrical systems.
A ground wire can be attached to a ground rod that is deeply buried, or it can be a length of copper wire buried near your foundation’s footings. A second physical ground is usually your cold-water supply pipe near your service panel.
Modern house wiring is color-coded so you won’t confuse your hot, neutral, and
ground wires with one another. This coding is standard everywhere—there is no room
for artistic creativity here. The wire colors are …

• Black and red for hot wires
• White for neutral wires
• Bare (unsheathed) copper or green for ground wires

The black, red, white, and green colors refer to the plastic sheathing that contains the wires themselves. If you have an old two-wire system , you won’t have a ground wire. An old knob-and-tube system sheaths both the hot and neutral wires in black, which isn’t exactly user-friendly when you’re trying to distinguish one wire from another. It’s important to understand the difference between the grounding wire and the neutral wire.
The neutral white wire carries the electrical current back to the power source after it’s passed through a load (a ceiling light, a fan, a stereo, and so on).
That’s the nature of an alternating current. The grounding wire, on the other hand, protects the entire system. The neutral wire is more correctly referred to as a grounded conductor. The bare or copper wire is a grounding conductor.

What is AC/DC?

When Thomas Edison and his crew invented a reliable electric light bulb, he followed it up by developing the power systems to run it, rightfully envisioning a future world full of light bulbs. (We usually refer to these as “light bulbs,” but “lamps” actually is the correct term. Bulbs are for planting.) Edison employed direct current (DC), which now is used in battery-operated gadgets in which the current flows from the negative terminal of the battery to the positive terminal. A battery is basically a container of chemicals whose electrochemical reactions produce excess electrons. Our electrical systems use alternating current (AC), which was developed by Edison’s contemporary, George Westinghouse, after he bought up patents from Nikola Tesla and William Stanley. Once again, someone with business sense trumped the scientific minds possessing the money-making ideas. It took Edison, the lampmeister, a few years to go along with this AC business, but he eventually told Westinghouse’s son to let his dad know he was right.
A direct current just means that the electric current flows continuously in one direction and keeps going until it finds something to run such as a radio or a light bulb. An alternating current flows in one direction—say, to a receptacle—and then flows back in the opposite direction. You might be thinking, so what? When was the last time alternating current was discussed on late-night talk shows? Probably never. Alternating current, however, does have some useful, consumer-friendly features such as the following:

• Through a series of transformers, an AC can be increased or decreased in value. (The current can be made stronger or weaker.) This means that, instead of a zillion watts of power heading for your panel box, you’ll get a reduced amount that you actually can use.
• Alternating current is efficiently transported over long-distance power lines.
• It’s easy to convert from AC to DC, but it’s expensive to go from DC to AC.

Staying Current

Electricity doesn’t do us much good if a bunch of errant electrons constantly change orchestras from one conductor to another. We want our electrons to move in a reasonably orderly fashion so they can do our bidding when we turn on the lights. A flow of electricity is called a current, and it’s carried into our homes through wiring from local electric utility companies. New electrical systems have the following three wires coming into your house:
➤ Two black or “hot” wires that carry the current to your service panel
➤ One bare neutral wire for carrying the current back to the power source and to ground An electrical current has a couple of different options, depending on your application.

Going with the Flow

Think back to your high school physics classes and all those diagrams of atoms with electrons spinning around a nucleus. (They’re the drawings that looked like really small solar systems.) Basically, electrons spin around because the protons in the atom’s nucleus carry a positive charge (+) that repels the electrons’ negative charge (–). If enough of the electrons decide to move on, preferably in a more or less uniform stream, we end up with usable electricity.
Electricity comes in several flavors, but the two we’re most familiar with are …
➤ Static electricity, in which the electric charges are stationary.
➤ Dynamic electricity, in which the electric charges are moving in a current.
When you were younger, the main value of static electricity was using it to shock unsuspecting siblings and cousins after you had walked across a carpet. If you didn’t do this when you were a kid, you can always try it at your next holiday dinner. Cats also are good targets, but their revenge usually is a messier affair. Why does the shock occur? Because some electrons like to travel, and they aren’t the most stable subatomic particles. When you walk across a carpet (some are worse than others), you pick up some of these hitchhiking electrons while leaving some of your own positive charges. They have to go somewhere, and your sibling’s finger or a doorknob makes a dandy conductor. If you touch a door frame, nothing happens because wood is a good insulator. That is, it does not allow electrons to easily move through it.
Static electricity is simply an imbalance of positive and negative charges. When you get zapped, you’re just the accountant trying to balance these charges. One place you don’t want to balance these charges, by the way, is with your computer, so you can either …
➤ Touch your metal desk chair before turning on your computer to get rid of any pesky electrons that could affect your computer.
➤ Apply anti-static spray periodically to your carpet so it will have a more positive charge and be less likely to give up its electrons. Static electricity may be annoying, but dynamic electricity is another story altogether.

About Electricity

We use and depend on electricity every single day. All we usually know about it is that it’s buried inside our walls, it runs our lights and VCRs, and we’re billed for it every month or so. Terms such as kilowatt hours, amperage, volts, and current are Greek to most of us. This is probably appropriate because the Greeks first described static electricity about 2,500 years ago. It was discovered that amber would accumulate a negative charge of static electricity when rubbed with sheep’s wool. Not known for a great sense of comedy, this probably became quite the party trick at Greek get-togethers. The word “electricity” has its root in the term electrum, which is Latin for “amber.” Understanding electricity is like understanding cooking: Once you know a bit about sautéing, cooking temperatures, seasonings, and how to make a decent pie crust, you can muddle through meal preparation and come up with more-than-edible results. If you know how electricity is produced and can toss around some vocabulary words, such as alternating current and resistance, you’ll be more comfortable with your electrical work. A task makes more sense when you understand its inner workings. This section isn’t going to give you enough information to challenge a Ph.D. in electrical engineering to a trivia contest at your local Jeopardy theme bar. You will, however, develop a working knowledge of electricity basics and how they apply to your own electrical system

Confused About Fuses?

Every fully electrified house has either a fuse box or a main panel box with circuit breakers. This is the distribution center for the power coming into your house. Without them, you would have one whopping current running through your walls that would burn out just about any appliance you tried to run on it.
Fuses were used until approximately 1950, when circuit breakers became the standard installation for new construction. The fuses most of us are familiar with are the round, screw-in glass types with a visible alloy strip inside the glass. These are called plug fuses. Cartridge fuses, which have a cylindrical shape, are the other common type of fuse.
If the current running across a plug fuse’s alloy strip exceeds the amperage of the fuse, the strip will melt, thus stopping the flow of electricity. There is nothing inherently wrong with a system using fuses, but they are dated and inconvenient. If you don’t have any spares around when one “blows”—you should always replace a fuse with one of the same amperage—you’re out of luck. The other problem with plug fuses is that a fuse with an amperage setting of 15, 20, 25, or 30 can be installed as a replacement for a burnt-out fuse even if the original size should have been 15 amps. Even though it is physically possible to install the wrong fuse, doing so could overload a circuit and might even start a fire in your home. To prevent this, the installation of an “S” type adapter will limit the maximum fuse size to 20 amps.

Circuit Breakers

A circuit breaker serves the same function as a fuse, but it’s a more complicated device. It also is reusable. When a current that exceeds the breaker’s capacity or rating passes through it, a pair of metal contacts is broken and remain so until the breaker is reset. A breaker can be reset an almost indefinite number of times, although repeated tripping is a sign of an electrical problem or overload. Any time a breaker trips or a fuse burns out, you must find the source of the problem before you reset the breaker or replace the fuse. Sometimes it’s only a single-occurrence problem such as running too many appliances at once. If you can’t find an apparent cause in your use of the circuit, you probably have a short in the system that must be .

More power needed each year

Modern electrical systems give us access to plenty of safe, dependable power. Around the turn of the century, it was a big deal to have a 60-amp service. Now, 200-amp services are common in many houses, and some larger homes are even getting 400 amps of power. We are dependent on electricity for our safety and well-being. One purpose of this book is to help you put it to the best use possible in your home. Any electrical system can be improved and adapted to your individual needs and specifications:

• A larger service of greater amperage can be installed.
• New circuits can be added.
• Existing circuits sometimes can be extended.

Although circuit breakers are the standard equipment for circuit protection in your home, fuses are still used in many other applications. Fuses with ratings as high as 10,000 amps and 136,000 volts are used in marine, automotive, telecommunications, and computer applications.Fuses provide circuit protection in motors, transformers, and an array of delicate electronic equipment.

• Lights can be added anywhere there is a need for them.
• Additional wiring can facilitate modern contrivances from garage door openers to barbecue rotisseries.

As you read on, you’ll learn how to perform these electrical chores by yourself or how
to evaluate your needs and discuss them intelligently with an electrician. Either way,
you’ll have power at your fingertips throughout your home.

The Logic of Electricity

Left to its own devices, electricity wouldn’t be much good to us because it requires some discipline to be useful. This discipline, in the form of electrical current, corrals the charged electrons that make electricity and directs them so they can power our lights, computers, and electric apple peelers. Your local utility company’s generators produce the electricity and then “pipe” it to your home through wires and transformers. The only time this is of any great interest to you is when there’s a disruption in the distribution system that results in your power going off and your digital clocks reverting to that annoying, flashing 12:00 signal when the power comes on again. Once the power lines enter your house, your interest naturally perks up. Here, the comfort and safety of you and your family are your number-one concerns.

Follow the Electrical Code

The installation of electrical systems in the United States is subject to local building codes. As a rule, these requirements are based on the National Electrical Code (NEC). (Canadians use the Canadian Electrical Code, or CEC.) The NEC carries no enforcement power and is written as an advisory document only, but for all intents and purposes, this is the main set of rules on which local codes are based. The NEC is the guiding authority for electricians and is not exactly bedtime reading for the rest of us. Local codes might be more stringent in some areas. As a homeowner or an electrician, you have to be aware of any specific rules that your local codes might impose.

Electrical codes spell out, among other things …

* Lighting requirements
* Receptacles needed per square foot of living space
* How the system should be grounded
* Circuit sizes
* Required wire gauge or size per individual circuit
* Special stipulations for kitchens, bathrooms, hot tubs, pools, fountains, and outdoors

Codes are like personal relationships: Everything can be going along just fine until there’s a misunderstanding or a misinterpretation of something someone has said. Then all interested parties have a problem. Electrical inspectors and electricians, both professional and do-it-yourselfers, sometimes have different interpretations of the code. For this reason, you want to be absolutely sure your work is done in the most straightforward manner possible, even if it means a little more expense or work on your part. After all, regardless of your interpretation, it’s the inspector who makes the final ruling. The authority having jurisdiction of the code will have the responsibility for making interpretations of the rules (Article 90-4). Leave literary license to wayward authors.

Safety Rules for Electrical Maintenance

It has been suggested that early electricians at the turn of the century were a paranoid lot. This was a new, untested medium that was replacing familiar gas lighting. These electricians weren’t interested in developing reputations as de facto arsonists. Wiring at the time was pretty simple to begin with, usually just lighting circuits, one receptacle per average-size room, and a very small service or fuse box. Electricians used lead solder followed by tape to join wires and do their work safely. Your dealings with electricity should be equally safe, whether you’re installing a new circuit or screwing in a light bulb. Electricity always is seeking an easy way to travel. Sticking your fingers, screwdrivers, or car keys into light sockets or receptacles provides these charged particles with an alternative path to moving along a wire. An improperly grounded toaster can cook more than your bagels. For now, you’ll need to keep a few rules in mind when dealing with your electrical system:

1. Don’t handle anything electrical if you’re wet or are standing on a wet surface.
2. Never overload a circuit beyond its capacity.
3. Extension cords are for temporary use only.
4. Never start an electrical repair or addition until you’re sure how to do the job correctly and the power is shut off.
5. When a problem is beyond your expertise, call a licensed electrician.

Mutual Respect

Franklin D. Roosevelt said that the only thing we have to fear is fear itself. He obviously never dealt with the IRS. We can include electricity as one thing we don’t have to fear, but we do need to respect it. You and your electrical system will get along just fine as long as you don’t demand more of it than it’s designed to provide. Most problems with electricity result from poor workmanship, code violations, and user abuse. Old systems were designed to power far fewer toys and gadgets than we have today. Trying to run three or four small kitchen appliances out of one receptacle, rather than running a new circuit, is just asking for trouble.

Do It Yourself or Hire It Out?

Electricians are one of the elite—and expensive— building trades. They are trained and tested to become licensed (a must when you’re hiring). They most likely can do a large job faster than you can. As with any trade, electricians come equipped with the tools and knowledge that you are now just

beginning to acquire. This doesn’t mean you aren’t up to the challenge—for most jobs, you will be. Once you understand how to run new circuits, replace lights, and upgrade old wiring, you’ll be able to do your own electrical work in a professional manner.
In addition to having a working knowledge of the code requirements and knowing how to install your wiring and fixtures, just what does this work involve?

Drilling and Pulling

The physical act of wiring is largely a matter of getting power from point A to point B in a manner approved by the code. Point A might be your main service panel (where the power enters your house), or it might be a receptacle on an adjoining wall. Either way, you have to figure out the best route to run your wire so A and B can be connected. How do you define the best way? That depends on your circumstances:

• Are your walls and ceilings open with the studs and joist exposed?
• Do you have to work around old plaster and lath or newer drywall?
• Is there basement, attic, or crawl-space access?

Much of an electrician’s time is spent drilling holes in wall studs and floor joist and pulling electrical cable from one fixture or receptacle to another. This work is tougher in a finished house, especially one with old plaster walls or limited access from either a basement or attic crawl space. This is timeconsuming work, and its cost can be difficult to estimate. In my opinion, these are perfect jobs for homeowners who can take their time drilling and “fishing” wires even if they don’t want to do the final connections or fixture installations. A couple of weekends or evenings with a commercial-quality drill and a roll of electrical cable can greatly reduce the time an electrician spends in your house—and can greatly reduce your costs.

Neatness Counts

I cannot emphasize enough the need for clean, neat, and accurate work when doing your own electrical jobs. Inspectors aren’t fond of homeowners doing their own wiring, and they probably will scrutinize your work more than the work of an electrician. Chalk it up to one more example of life being unfair, or see it as motivation to do the best work possible. (How’s that for making lemonade out of lemons?) A new electrical service that’s been done well is a beautiful exercise in symmetry. All the wires entering the service panel are installed at neat right angles without any excess length. Wires running along exposed basement floor joist are taut, stapled, and secured. The point of the staple is to gently hold the cable in place. It is very easy to damage the outer sheath of NMB (nonmetallic) cable if you aggressively pound staples against it.
Cable inside receptacle and switch boxes is cut clean and is folded in and out of the way at the back of the boxes. These are not inordinate standards but the ones an inspector expects to see. You should expect them, too, whether you do your own work or hire it out.
Can you get these results as a novice? Of course you can! It will take you longer than a trained electrician, but so would just about any work that’s new to you. That’s why you read this blog. This text—and a few good tools —will see you through most electrical jobs with inspector-pleasing results.

Simple Projects First

Before you go yanking your old fuse box out, convinced that you can replace it before dinnertime with new circuit breakers, look for a small job to do first. Most older homes have at least one receptacle or switch that needs replacing. There are other jobs to consider as well such as …

• Adding extra garage lights.
• Running a dedicated circuit for your office computer.
• Installing a bathroom fan.
• Adding lights to your backyard.

These are good jobs for practicing your evolving electrical skills without causing too much disruption around your house. They all involve applying for a permit, scheduling an inspection, calculating an electrical load, running wire from a power source to a fixture, installing the fixture, and making the final connections of wire, fixture, and power source. Each of these jobs is a microcosm of a larger project such as rewiring your entire house, and each is a good confidence booster. You can even take snapshots of your work to carry around in your wallet, but be prepared for some strange looks from your friends when you pull them out for showing.