Know Your Circuits with a Circuit Map

Electricians follow the minimalist school of writing: They write as little as possible when listing the circuits on the form inside the service panel door. An electrician will write “Lighting circuits,” for example, across the space designating one or two specific breakers. That’s all well and good, but a more useful description would say, “Ceiling lights in master bedroom and north bedroom, in second-floor hallway, and at top of stairs.” These written descriptions need more room than most factory-supplied lists provide, unless the writing is very small.

In a new house, the electrician’s list usually is adequate because the wiring is so straightforward. In an old house, however, the list needs to be more specific, especially if past homeowners have added their own electrical marks when they lived in your home. Every owner has different needs, and they manifest themselves with receptacles, lights, and switches in places that will make no apparent sense to you but are perfectly logical for someone else. These include lights in crawl spaces, switches on attic rafters, and receptacles in closets. You don’t need to know their history, but you should know which fuse or circuit breaker controls them, especially if they are tied in to the middle of a circuit and can potentially cause problems. Drawing your own circuit map can be done alone, but it is best done with some helping hands. To come up with your map, you’ll need the following:

• Paper and pen for recording
• Lights and radios to plug into receptacles
• Extra people spread around your house

Circuits and Runs

Circuits can be divided by type:

• General-purpose or lighting circuits
• Dedicated circuits
• Small-appliance circuits

Lighting circuits include most receptacles in living areas other than the kitchen, bathrooms, and workrooms. This is appropriate for most receptacles because we generally use them for small loads such as floor and table lamps or clock radios. Some receptacles will only be used for night-lights; others might rarely or never be used. Even light fixtures have varying loads depending on the wattage of their lamps. They can vary from 25 watts to 150 watts.

What happens when you plug in something larger such as a room air conditioner? What if you have a water heater or an electric range that also requires large amounts of current? These loads call for dedicated circuits, which are so-named because they only supply power to one specific load.
Dedicated circuits include those for …

• Major appliances.
• Refrigerators.
• Computers.

It’s easy to understand why a major appliance needs a dedicated circuit, but what about refrigerators and computers? Even a large refrigerator-freezer combination is rated at about 500 to 700 watts, and a computer is far less. (My notebook PC is a minuscule 36 watts.) These fall into a different category of dedicated circuits that aren’t based on a demand for electrical current but on their specific activity. It isn’t critical for your refrigerator to be on its own circuit from a power-demand standpoint, but if another load somewhere else on the circuit’s run trips the entire circuit, your refrigerator will shut down, and you will be looking at a lot of spoiled food. Some jurisdictions codes require that the refrigerator be on a dedicated circuit.

Computers don’t store food, but they do store your data. Most people readily agree that we should back up and save our documents and spreadsheets while we’re working on them, but then we cheerfully continue working without doing either.

Amps, Watts, and Wire Gauge Working Together

You remember that amps, or amperes, are a measure of an electrical current’s strength or flow. A watt measures the electrical power itself. That is, it measures the amount of electricity consumed by an appliance or another fixture as it converts the electricity into something useful to us. A circuit is sized to allow a certain amount of electricity to run to a given number of loads.

The loads are measured in watts, which is why you can only have a certain number of receptacles and lights on a circuit. Too many running at once demands more juice than the circuit can safely provide before a protective device in the form of a circuit breaker or fuse steps in like a responsible bartender and cuts you off.

The amount of current carried to the various loads also is determined by the size of the wire running between the service panel and the loads. If your wire is too small for the amount of current the load is demanding, it will have a high resistance and will overheat. This is okay for the heating element in your toaster but not for your house wiring. A 20-amp circuit, which usually runs small appliances, requires No.12 wire. Many electricians recommend No.12 wire as the minimum size wire for residential use, even though the code accepts No.14 wire as the minimum-size conductor for branch circuit wiring.

Branching Out to Break Up the Load

You could connect all of your 120-volt electrical loads—lights, bedroom receptacles, the refrigerator, and so on—to one big circuit breaker, and they would still function. Replacing a broken switch or installing a new light fixture then would mean turning off all the power to the house rather than just the power to one particular room. If your housecleaning service trips this giant breaker with a new 55-horsepower industrial vacuum cleaner while you are out of town and is afraid to reset it, you can kiss that frozen Copper River salmon in the freezer good-bye.
Electrical current is broken down into individual circuits—called branch circuits—for safety and convenience. You don’t want the entire house to go dark because a GFCI in the kitchen tripped due to a faulty appliance. Each circuit is designed to carry a certain amperage and to provide enough current to meet the wattage demands of receptacles, lights, and appliances. The following figure shows a standard residential distribution of circuits.
A circuit is laid out logically, or at least it should be. This means that a 15-amp lighting circuit will control lights in, say, three continuous rooms rather than in three rooms at opposite corners and on different floors of the house. Several forces work together to help a circuit do its job safely.

Understanding Electrical Panels

Every electrician has favorite electrical components to recommend, and this includes service panels. Electricians also have panels that they avoid and existing, older panels that they recommend tearing out yesterday if not sooner. This is touchy ground, and anything I or the electricians I have worked with recommend will be subject to criticism in some quarters. With that caveat, I can recommend the following guidelines for choosing a panel:

• You get what you pay for, so skip the low-end panels.
• Ask as many electricians, electrical suppliers, and builders of high-end homes as you can what panel they recommend; one or two names should keep coming up.
• Buy the best panels made by your manufacturer of choice rather than lower-end units made to compete with similar low-end units from chain discount stores.

Consider what a panel does: It acts as the major line of defense in the event of an electrical problem. You want the best panel possible rather than the most basic. They all will be UL-approved, but it’s better to go with a panel that will meet higher standards than the bare minimum. You wouldn’t buy the cheapest brakes for the family minivan, and this is the same attitude you should take with your electrical panel. What does my electrician recommend? He uses the Square D QO panel. Others recommend Cutler-Hammer or Siemens. All of these are reliable brand names that will serve you well.

The More Power the Better

Harry Truman once made a comment about fully equipped armed forces, saying something like, “If we’ve got ’em, then we won’t have to use ’em.” He figured the more power the country had, the more of a deterrent it would be to future aggressors (if only he’d been right). He was on to something about power, though: It’s better to have plenty of it than to not have enough. The same is true with your electrical system. There is nothing wasteful or ecologically sinful about having a minimum 200-amp service in your house. No one says you have to use all that electricity all the time or even ever.

Heed the Boy Scout motto: Be prepared! None of us knows what the future will bring, except maybe dial-up psychics: They know your call will bring them $2.95 a minute. Everything else is a roll of the dice. You might add a second story to your house, set up a woodworking shop in the basement, or double the size of your kitchen. You even could add a casino extension off your garage if your state legislature decides that home-based gambling operations are more in keeping with its ideas about family values. Any and all of these possibilities require electric power. If you’re replacing your current system, think more rather than less because, in this case, less is definitely not more.

The Main Shutoff

Fuse boxes and service panels both have some kind of main shutoff mechanism, and you should know how to use it. The NEC says that you cannot have more than six disconnects—no more than six fuses, breakers, or levers of some kind—to turn off the service. Fuse boxes usually have either a single pulldown handle or two 50-amp pullout fuse holders to disconnect the service.
In a service panel, you will have either a main breaker or a series of breakers in the top half of some older panels that, when shut off, will disconnect the service. Remember, even with the breakers shutoff or the fuses removed, without the meter removed from the meter socket, the panel is still hot where the large wires come in from outside your house.

In case of an emergency in which you must get the power off quickly and cannot identify the specific fuse or breaker, the main shutoff will do the job. Keep in mind that your entire house can go dark. Be sure to have a flashlight close to your fuse box or service panel.

Tripped Circuit Breaker

Breakers, as previously explained, “trip” when a metallic strip heats up, bends, and forces springloaded contacts apart. After tripping, they can be reset by pushing the breaker’s switch all the way “off” and then back over to the “on” position.
When resetting a circuit breaker, be sure to …

• First find out what caused the breaker to trip and shut it off.
• Use only one hand and keep the other one away from the service panel.

A circuit map will identify the circuits controlled by each breaker or Circuit breakers, like fuses, are rated by amperage. Don’t even consider installing a higher-rated breaker in place of a lower one. If you have repeated tripping, you’re overloading the circuit and need to change your usage habits or upgrade the circuit.

Fuses safety basics

Although there’s a variety of fuses, most old residential systems use the glass, screw-in type called plug fuses. These fuses feature a narrow metal strip, visible through the glass, that quickly melts when too much current is starting to move through the circuit. Fuses are rated by amperage and cannot be reused after they burn out or “blow.” A fuse system generally is safe if it’s used according to its design. This means …

• Always using the correct size fuse.
• Being sure the fuse is screwed in tightly.
• Not listening to your old uncle Bob, who says you can replace a fuse with a Lincoln-head penny and call it good.

The glass of a blown-out fuse might look smoky, or more noticeably, the strip will be melted or separated. Before replacing it, you should turn off any electrical load that might have caused the overload.
Some electricians recommend that you also turn off the main switch to the fuse box before removing and replacing the old fuse. Whatever you do, be sure to keep one hand behind your back or in your pocket! You don’t want both hands near the box, because if both accidentally touch it, you can become part of a circuit and electrocute yourself.

Circuit Breakers vs. Fuses

Circuit breakers and fuses perform the same task: They interrupt electrical power when the current demand is too high. If you plug a 2,200-watt personal surfing pool complete with Oahu-inspired monster waves into a 15-amp circuit, be prepared to wipe out along with the power. If the breaker doesn’t trip or the fuse burn out, the wire connecting the receptacle to the panel could overheat and possibly start a fire. You probably wouldn’t realize anything was burning because the wiring is concealed inside your walls. Circuit breakers have been the mainstay for residential electrical installations for more than 40 years. They’re convenient, dependable, and reusable. What’s not to like about them?

Are You Feeling Polarized?

Have you ever noticed how some receptacles (and all new ones) have two different size slots? These are polarized receptacles, and they’re the perfect fit for polarized plugs. In each case, one side (the slot of the outlet and one prong of the plug) is larger than the other. This is not done to intentionally annoy you, but if you have an old house, it can be a real inconvenience when plugging in new electrical devices.

A polarized receptacle is constructed so a polarized plug can be inserted only one way. It also ensures that the hot leads and the neutral wires line up from outlet to plug. It might be tempting to file down the larger prong on a polarized plug, but trust me, this is a bad idea, too. These are all parts of a system, and they’re made to work together and be kept intact. This is no place for quick fixes. Either adapt to the limitations of your older electrical system, or bring it up to date.

Understanding Two-Wire and Three-Wire Systems

A two-wire system means you don’t have a grounding conductor. This is the bare copper or green-insulationclad wire attached to a grounding electrode outside your house. Alternatively, the grounding conductor can be attached to a water pipe near your electrical panel.

Your first clue to determine whether your system has a grounding conductor comes from your receptacles. A two-pronged receptacle usually doesn’t have a ground; a three-pronged outlet should have a ground.
An older house might well have three-pronged outlets, but there is no guarantee that they were installed with grounds (another peril of uninspected remodeling work). To be certain, you must either …

• Test each outlet with a circuit tester, which will indicate the presence of a ground wire.
• Take the cover plate off each receptacle and look for the ground wire.

Of the two methods, using a circuit tester is easier. If your system isn’t grounded, it doesn’t mean you’re in grave danger and should refrain from turning on the lights ever again. It does mean, however, that it’s a dated system that lacks a modern safety feature—a safety feature that people lived without until the 1960s. Unless there’s been a deep conspiracy to cover up massive electrocutions of homeowners over the years, you can still live with an old two-wire system (but it’s always a good idea to upgrade).

A grounded receptacle connects any exposed metal sections of an appliance or lamp to the house grounding system. This means an errant current shouldn’t pass through the metal shell of your washing machine and turn your wash day into something unexpected. A three-pronged, grounded receptacle is the made-to-fit receiving end for a threepronged plug. Remember, electrical systems are nice and logical. If you have a twopronged outlet and a three-pronged plug, they don’t go together, no matter how hard you push on the plug. Before you ask, cutting off the grounding pin from the plug is a bad idea. Buy an adapter, which is available at any hardware store, instead.

Are You Up-to-Date with the Latest Electrical Code Revision?

Now that you’ve got a hint of the hell-and-brimstone that awaits you if you ignore electrical safety and code requirements, you can take a fresh look at your own system. As we’ve already mentioned, a new system can almost be ignored until you’re ready to add to it. A system meeting the 1996 or 1999 NEC will be grounded, will have plenty of receptacles including GFCIs, and will have power properly distributed among a series of circuits throughout your house.

What if you have an older system or one that’s been altered? Your home might have had an addition or two put on by past owners. How can you be sure these were done according to past building codes? Let’s start with some basics as you review your electrical system.
There are some basic differences between older and newer electrical systems, such as …
➤ The presence or absence of a grounding conductor.
➤ Fuses versus circuit breakers.
➤ Nonpolarized outlets versus polarized outlets.

Understanding About Underwriters Laboratory

Underwriters Laboratory is the organization that brings us the ubiquitous “UL” tags on just about everything we plug in or turn on. What does this group do? In the organization’s own words, UL “is an independent, not-for-profit, product-safety-testing and -certification organization.” Underwriters Laboratory was established in 1894 to test products for the emerging electrical industry. It has managed to attach more than 14 billion UL tags to products all over the world.

UL is the leader in product testing and certification. If a manufacturer wants its new gadget to gain ready consumer acceptance, it applies for the UL tag, because no retail outlet in its right mind would sell anything electrical without it. You can find the organization at www.ul.com on the Web.

The UL, along with the Consumer Product Safety Commission and the National Electrical Manufacturer’s Association, helped establish the not-for-profit National Electrical Safety Foundation (NESF) in 1994. The Foundation’s mission is to improve our awareness of electrical safety at home, work, and school. The NESF’s Web site, www.nesf.org, points out the following cheery statistics:

• One person is electrocuted in his or her home every 25 hours, and more than 350 people die in over 40,000 residential electrical fires every year (Consumer Product Safety Commission data).
• One worker is electrocuted on the job every day (Occupational Safety and Health Administration data).
• Personal-property damage from fires exceeds $2 billion a year. These are not-so-subtle hints that you can’t take electrical safety for granted. The NESF offers tips, Web links, and a safety booklet, and it’s all free for the asking.

What is CEC?

Canadians use the Canadian Electrical Code (CEC). You might wonder what this has to do with electrical work on this side of the border, but Alaskans (state motto: It Doesn’t Get Any Colder Than This) have had problems in the past with Canadian-built outdoor work modules (portable buildings). Differences in the two electrical codes have resulted in some modules being unacceptable without costly upgrades to meet the NEC. You could probably argue that Alaska should be part of Canada, but it isn’t, so the CEC isn’t acceptable there.

Know the Local Rules, Know the Local Inspectors

Ultimately, the NEC isn’t the final judge and jury of your electrical work. This role belongs to your local electrical inspector who enforces your local electrical code. How does your local code differ from the NEC? It depends on where you live. Some municipalities stick with and solely enforce the NEC; some have additional rules. Remember, your local code determines how you or your electrician will do your electrical work, so you must know the regulations.
The electrical inspector wears a variety of hats. An inspector …

• Interprets the NEC rules and regulations.
• Approves or rejects electrical work.
• Approves fixtures and materials.

Is an inspector always right? Let me put it this way: If you question a judgment or ruling, you had better be able to back it up by quoting chapter and verse from the code. No one is perfect, and an electrical code is an involved and complex document. Mistakes and misinterpretations are made on both sides, but the inspector has the final word. Take some tips from Mr. Etiquette:

• Do your best work, and do it neatly.
• Don’t try to hide anything or take shortcuts.
• If your inspector believes you’ve erred in your work, listen politely and see what you have to do to resolve the problem.

It isn’t the inspector’s job to show you how to do your work. As a homeowner, you’ll have to establish your credibility and competence to do the job, even more so than a trained electrician. An inspection is like the speed limit—you might not like it, but it’s there to protect you.

You and the Code

The NEC exists for your protection. I know we live in an era of business-guru authors and self-improvement advisors extolling everyone to “think outside the box,” to develop new paradigms, and to seek out the “wow” in everything we do. That’s fine, just don’t try it with your electrical work. The code will help keep you and your family alive and your house from burning down. You can be as imaginative as you want when it comes to selecting fixtures or adding lights, but they have to be wired and installed properly.
Just in case you decide to seek your bliss and express yourself with electrical work that isn’t up to code, your local inspector will be equally expressive, but in a way that won’t make you very blissful.

Understanding The National Electrical Code

The National Electrical Code (NEC) is the guiding light behind most electrical installations in the United States. As a rule, local regulations include the NEC along with any specific ordinances imposed by individual building departments. The fact that so many state and city agencies use the NEC affirms the excellence of this code. As a culture, we might have our disagreements from one coast to the other, but we do agree on the National Electrical Code.

Interestingly, the NEC is not mandatory and therefore has no regulatory control. It’s strictly a set of voluntary guidelines, which is a good thing: If Congress had gotten hold of it and tried to turn it into legislation, we’d still be using candles and kerosene lamps to light our homes. The NEC is just over 100 years old, and it has changed with the times. The advent of electrical power brought with it the need for standards for equipment, installations, and usage. The initial concerns around electricity were mainly about property protection. Fire underwriters were especially concerned, because they were taking losses due to electrical fires.

New York, the late-nineteenth-century center of the universe, wrote the first requirements for electrical safeguards in 1881. More codes by different industries followed, and in 1892, the Underwriters National Electrical Association consolidated these various codes, although there was still no universal acceptance of one set of rules. Saying enough was enough, the National Electric Light Association called a conference in 1896 to come up with one standard set of rules. The conference included utility representatives, underwriters, inspectors, and just about every key player who was involved with this new electricity business. They diced, spliced, and blended the best parts of all the existing American and European codes.

They then tweaked it during a review process, and in 1897, they came up with the National Electrical Code. There have been 48 editions of the code, and the next one is due out in 2002. The National Fire Protection Association (NFPA) has administered the NEC since 1911. Harking back to the original NEC, the current code is a product of group consensus with an even greater variety of contributors including labor unions, testing laboratories, regulatory bodies, and consumer groups.

The NEC goes well beyond home electrical systems.
Among other things, it covers the following:
➤ Fiber-optic cables
➤ Antennas
➤ Fire alarms
➤ Marinas
➤ Carnivals, circuses, and fairs
➤ Mobile homes
➤ Gasoline dispensers
Espresso stands and popcorn wagons might not specifically be named, but they’re covered, too!