A neutral wire IS the common current carrying wire in a multiwire electrical circuit. It is generally the wire to which all current carrying conductors are voltage referenced. It may or may not be grounded, depending on the circuit requirements.
The "common" is the "neutral" or "ground" wire, depending on the type of circuit. In normal US residential wiring, you'll have a black "hot" wire, a white "neutral" or "common" wire, and a green or bare "ground" wire.
The neutral is always referenced to ground at one, and ONLY one, point. If you touch the neutral to ground anywhere else, you will create the aforementioned ground loop because the grounding system and the nuetral conductor are now wired in parallel, so they now carry equal magnitudes of current.
This happens when the hot and neutral wires get flipped around at an outlet, or upstream from an outlet. Reversed polarity creates a potential shock hazard, but it's usually an easy repair. The other wire doesn't get connected to the earth, and it's called the ungrounded conductor, or hot wire.
Here's what happens when somebody wires a GFCI receptacle with the load and line wires reversed: The GFCI will work, in the sense that you can plug in a hair dryer and the hair dryer will blow hot air. If the load and line wiring gets messed up, a ground fault (radio in the tub) won't trip the GFCI.
If the multi-colored wire is black and red, the black wire is the negative wire, while the red one is positive. If both wires are black but one has a white stripe, the striped wire is negative, while the plain black wire is positive.
My wall outlet has 2 black wires and 2 white (2 are the power in and 2 provide power out to another outlet). The Ground wire coming out of this outlet is a green wire, this would connect to the bare copper ground wires that are connected you your existing outlet.
Here's what happens when somebody wires a GFCI receptacle with the load and line wires reversed: The GFCI will work, in the sense that you can plug in a hair dryer and the hair dryer will blow hot air. If the load and line wiring gets messed up, a ground fault (radio in the tub) won't trip the GFCI.
Most likely the neutral wire is white and the hot wire is red or black, but test to make sure. Identify the neutral wire in the fixture by looking at the wires. In most modern fixtures the neutral wire will be white and the hot wire is red or black. In some types of fixtures, both wires will be the same color.
Electrical Wires
The black wire is the "hot" wire, which carries the electricity from the breaker panel into the switch or light source. The white wire is the "neutral" wire, which takes any unused electricity and current and sends them back to the breaker panel.Inside an outlet's electrical box, the black (hot) wire should be connected to the brass-colored terminal on the outlet. The white (neutral) wire should be connected to the silver-colored terminal. If these connections are backward, the polarity is wrong.
The bare or green-wrapped ground wires serve as a backup to divert the power safely away in case of an electrical fault. In most cases, two black wires will be attached to the switch's two terminal screws.
Older homes typically have this problem — most of them were built with two-wire (hot and ground) systems, that didn't require a third (neutral) wire. But that's not a reason to despair. It's still possible to have home automation even if the house doesn't have a neutral wire.
Old wiring can be fraught with problems that can not only run up your electric bill, but can also pose fire hazards. Old fuses and circuit breakers may not be sufficient to handle your modern family's electrical draw. Arc faults in poorly maintained older homes can cause a drastic increase in electricity use.
The majority of 1970s houses do not need rewiring. They will probably just need a consumer unit and earthing upgrade. If you have a consumer unit change then the electrician will have to inspect a lot of the property anyway.
The power wire that is grounded is called the “neutral” wire because it is not dangerous with respect to exposed metal parts or plumbing. The “hot” wire gets its name because it is dangerous. The grounding of the neutral wire is not related to the operation of electrical equipment but is required for reasons of safety.
Place the roll of wire next to the breaker box and pull the wire according to your diagram to the closest outlet or switch for each circuit. You can also run the wires straight through the box. Any wires sticking out of the box may just get dry walled over or could get cut from the electrical box.
My short answer to the question is that “Yes, lights and power outlets (a.k.a AC receptacles) can be on the same circuit controlled by a circuit breaker, especially in a single family residential house”. The circuit branch controlled by the 15A circuit breaker has a couple of lights and AC outlets connected.
In residential, 15 amp circuits are abundant, 20 amp circuits are scarce. Look in your breaker/fuse box at home, and in other homes, and count them up - the 15's and the 20's. The power (amperage) is there.
Most homes ideally have 100 or 200-amp breaker boxes depending on the amount of electricity that the panel needs to handle and the number of circuits that are added to the main circuit breaker panel.
Divide 180 by 120. The calculated load for one receptacle supplied by 120 volts is 1.5 amperes (180 ÷ 120 = 1.5). To find the maximum number of receptacles permitted on a 15-ampere breaker, divide the rating of the breaker by 1.5 amperes (15 ÷ 1.5 = 10).
