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?