As long as we have had generators and motors and electric lights, we have had copper wire. Copper has always been the standard material for electrical wiring systems, in all types of buildings including our nation's sixty million wired homes. It is the only wiring approved by all electrical codes, nationwide.
Why copper? Because, as hard as man has searched for a substitute, he has not been able to find one that can do the job as reliably or as economically as copper.
Copper has several important properties that make it a "natural" for electrical wiring. More than any other non-precious metal, it is the best conductor of electricity, packing more power into a given diameter of wire than any substitute material. Copper is also easier to bend, yet tougher. With copper, connections are easy and sure. And, because it has a high melting point, it can take surprisingly heavy overloads or current surges without damage or danger.
Perhaps the best eyes through which to look at the advantages of copper wiring are those of the electrical contractor, because he is, in a very real sense, responsible to both the builder and the consumer, and he knows that his reputation and the success of his business rest squarely on his workmanship and choice of materials.
A service call - or "callback" - is a visit nobody wants to be bothered with, either the electrical contractor or the homeowner.
Here, then, are some reasons why electrical contractors prefer copper:
- Copper does not creep or loosen at connections
Constant expansion and contraction under "load, no-load" conditions can cause non-copper materials to "creep," a process which results in the loosening of terminations. In turn, loose connections tend to heat up, and will sometimes arc dangerously.
The only way to avoid these problems is to check all terminals periodically, tighten screws and connecting devices - or to specify copper initially.
- All-copper systems present no problem of incompatibility
Copper is, naturally, compatible with itself. It is not, however, compatible with aluminum wire or connectors. If the two metals are joined, a galvanic action can occur and anodic corrosion can disintegrate the aluminum. This is the reason that most appliance and electrical equipment manufacturers use copper lead wires for connection to building wiring systems.
- Installation of copper wiring is well known
This is important to the electrical contractor because it means that his electricians do not have to take time out for special instruction and qualification to install non-copper wiring.
- Copper eliminates worry about surface oxides
Copper does not need the special surface preparation or anti-oxidant pastes on connections and splices required by non-copper wiring. Even copper's oxide conducts.
- Copper is easy to work with
Electricians definitely prefer to work with copper if the choice is theirs. It strips easily, bends easily without nicking or breaking, has the "pull-through" strength that's important for pulling wire through conduits and other tight places, and it can be connected without special lugs and fittings.
- Copper can be easily joined
Some codes require soldered joints. Copper can be easily soldered. Substitute materials cannot.
- Copper can withstand overloads
Current, or load surges can play havoc with a wiring system. Of all wiring materials, copper is best able to withstand overloads. Overloads will not loosen copper joints, either.
- Rewiring is easier with copper
- When a home is being remodeled or its wiring system is being expanded for increased capacity, copper wire is best because it is smaller in diameter, requires less space.
- Copper is readily available
Copper wire is readily available in every city in a wide range of standard sizes.
- Copper has nationwide approval
Copper is approved by electrical codes nationwide with years of excellent performance serving as testimony.
These are solid reasons why copper is really your best buy in wiring. Copper's performance is respected by professional electricians. They know from experience that it is false economy to "save" money by using a substitute material. Copper is a quality product. It may cost a little more to begin with, but first cost is the least cost when it's the last cost.
Next time the decision is yours, insist on copper wiring. You'll be happy you did.