A ground wire, sometimes also referred to as a “grounded” wire, is an electrical wire that neutralizes and protects devices, appliances, and buildings from current problems and shocks. Originally the term applied only to wires that were actually connected to the Earth, and in many cases this is still true. Electricity running to homes and office buildings almost always has this in-ground feature. The phrasing has become pervasive, however, and is often used in contexts where there is no actual contact with the literal ground. Cell phones, for instance, may be said to have ground wiring; many small appliances also have wires with this name. In these cases the “grounding” that is happening is really mostly about stabilization.
Importance of Neutrality
Electrical conductivity is somewhat complex, but in almost all cases signals are carried across at least three wires. One is considered hot, one neutral, and one grounded. Hot wires carry signals to something, while neutral ones carry it away. Neutrality is really important here because electricity can’t just run to something in an unchecked way; if it did, it could cause shocks, sparks, and fires. Devices, appliances, and fixtures need to get just enough current to perform their function. Once that threshold is met, the current needs an outlet, which is normally the role of the neutral wire.
Ground wires are, essentially, a type of insurance. When a neutral wire does not function, the grounded aspect will ensure that an appliance does not give off a dangerous electrical shock. In homes this wire usually works alongside circuit breakers to prevent electrical fires and other dangers. Most of the time they’re silent or still, but when needed they play an essential role.
Most modern homes and buildings are built with an expansive inner electrical circuitry that feeds outlets and wall sockets. Most of the conductivity happens within the walls or under the floorboards, but usually all connects back to a central circuit breaker that, in most cases, is actually grounded to the physical Earth beneath the structure. Most electricity comes up out of the ground as it is, and the Earth is widely believed to have a stabilizing, essentially constant current.
Red and black wires are usually hot, while white wires are neutral. Grounded wires may connect to sockets in homes and buildings, but not always. When they do they’re often green or yellow. When a white wire is broken, stray current is no longer carried away from the socket and, by extension, whatever is plugged into it. The same thing happens when outlets are overloaded. In both of these cases neutralization is not possible unless there’s a ground wire. It is this wire that will assume the deflected charge and trip the corresponding circuit breaker, stopping any electrical current.
Appliances will operate normally without the help of ground wires, though most will nonetheless include them. In fact, if one is broken or missing, most people will not be able to tell the difference. If a large amount of high voltage has come in contact with the appliance, however, users may get a hefty electrical shock.
The term “ground wire” has become somewhat standard, even for devices that don’t stay plugged in to operate. Mobile phones are one example. It’s common for electricians and engineers to name one of the wires in a phone’s internal circuitry as the “grounded” wire, mostly by analogy. This wire works the same way and has the same function as one actually connected to the Earth — namely, to neutralize currents in case of fault or overload and to provide a return path for unneeded charge — but it is usually sourced a bit differently.
Dangers and Precautions
These sorts of wires aren’t normally dangerous when they aren’t being used, but since they are volatile or “live” when they’re carrying a current it’s best to use caution when handling them. People who are working with electrical wires, whether installing or repairing, usually have to be very careful to identify everything before rearranging or snipping. It is usually very difficult to know if the backup wire is actually carrying a current just by looking at it, which makes erring on the side of caution the best bet in most cases.
There are also a few important things for people to keep in mind when buying a home. Most experts say it’s crucial for buyers to ask a home inspector or electrician to inspect a home's electrical network, paying special attention to circuit breaker boxes and grounded wires. While some homes may appear to be in good condition, faulty wiring can lead to shock and fires. Nearly every country has an electrical standard that includes electrical grounding that all homeowners must adhere to, and these rules exist in order to prevent fires and other dangerous incidents.