Home Wiring Basics
Residential electrical wiring systems start with the utility’s power lines and equipment that provide power to the home, known collectively as the service entrance. The power is run through an electric meter, which records how much energy is used in the home and is the basis for the monthly electric bill. In general, the utility company’s jurisdiction stops with the meter. After that point, all of the electrical equipment is the homeowner’s responsibility.
The service entrance is the equipment that brings electrical power to the home. Most residential service includes three wires: two cables carrying 120 volts each (for a total of 240 volts) and one grounded neutral wire. If the cables are hung overhead, they are collectively called a service drop. If they are routed underground, they are known as a service lateral. A service drop connects to the home at a service head, or weather head, on the roof or exterior wall of the house.
Once the power reaches the house via the service drop or service lateral cables, it passes through the electric meter, which may be mounted on an exterior wall or may be located inside the home’s breaker box. The meter records all electricity used by the home, measured in kilowatt-hours, or kWh. A 100-watt light bulb burning for 10 hours uses 1 kWh of electricity. Meters may be analog or digital type, although most new meters are digital and can be read remotely by the utility company.
Main Service Panel
The main service panel, commonly known as the breaker box or circuit breaker panel, distributes power to all circuits throughout the building. Each circuit has a breaker that can shut itself off in the event of a short circuit or overload to cut power to the circuit. Old homes may have fuses instead of breakers. Fuses are just as effective as breakers, but most new panels today use breakers instead of fuses.
It is important to note that power coming from the service lines to the electric meter, and then to the main service panel, is always live. Before working on these areas the power company must shut off the power. The power going out of the panel to the household circuits can be shut off by the main breaker in the service panel, but the power coming into the panel is not affected by the main breaker.
The power is transported out of the panel through a wire. This wire is insulated with a red or black cover. The power returns to the panel through a neutral wire covered in a white insulation. There is a third wire provides the ground and it’s encased in green insulation. Those two wires will connect to a neutral bar in the panel. It’s recommended to get thicker wires for safety reasons, if the wires become too hot they could overload and the insulating case could melt.
Fuses and Breakers
Both of these are installed as a safety precaution. In case of the power overloading, the breakers or fuses shut off and prevent the wires from overheating. The breakers could be reset in case it has to shut off due to overloading. A fuse needs to be replaced in case it blows.
understanding-electrical-installation.jpegHere is your how-to guide on electrical installation so you can know how to set up electrical wiring in your latest home build without any hassle.
Do you feel intimidated when your construction project reaches the electrical wiring stage?
Electrical installation might seem intimidating, but once you understand how it works you’ll realize it’s very basic. Once you learn the basics you can begin to look at more complex electrical setups.
This guide will walk you through basic electric installation. Let’s get to it.
How Does Power Moves Through?
In order to understand how an electrical installation operation works, first you need to learn where the power comes from.
Th electric company sends power to the house through the distribution lines which then pass through the meter. This linear power movement later enters through the panel and into the circuit wires. Then the power passed into each outlet of the house.
The meter is connected directly to the main source of power, which comes from the electric company. It’s located on the outside of the house so that the electric company can perform meter reads.
This device keeps track of how much electricity was used each month. It measures power in kilowatt-hour units (kWh).
Main Breaker Panel
Once the electricity passes through the meter, it goes directly to the main breaker panel. The size and capacity of the panel will determine the maximum amps of electricity that can pass through the house.
The panel has the main breaker switch, which can be turned on and off to prevent overloading, fires, or electrocution.
Directly below the main breaker, there are smaller breaker switches. Those switches are responsible for delivering electricity to the other rooms in the house. If you want to cut the electric supply to one room, simply turn off that switch.
The power is transported out of the panel through a wire. This wire is insulated with a red or black cover. The power returns to the panel through a neutral wire covered in a white insulation.
There is a third wire provides the ground and it’s encased in green insulation. Those two wires will connect to a neutral bar in the panel.
It’s recommended to get thicker wires for safety reasons, if the wires become too hot they could overload and the insulating case could melt.
Fuses and Breakers
Both of these are installed as a safety precaution. In case of the power overloading, the breakers or fuses shut off and prevent the wires from overheating.
The breakers could be reset in case it has to shut off due to overloading. A fuse needs to be replaced in case it blows.
Terms to Know
Also called amperes, are the units used to measure electricity.
Watts are the units used to measure the amount of power an electrical device uses. They can be calculated by multiplying amps times volts.
Volts refer to the force contained in a power source. For example, most common household wires carry 120 volts.
Before starting any installation work, first and foremost thing is the concern of safety of the personnel. Electricity is dangerous, direct or indirect contact of electrical equipment or wires with the power turned ON can result serious injuries or sometimes even causes to death. Follow the below steps to maintain the safety at the workplace.
- Always use safety equipment like goggles, gloves, shoes, etc. and avoid the direct contact with live or energized circuits.
- Have the skills and techniques to distinguish the exposed live parts of the electrical equipment.
- Disconnect the source supply while installing or connecting wires.
- The power supplied to the installation must be controlled on the main switchboard which should consist of circuit breaker.
- Conductive tools and materials must be kept at a safe distance from live parts of the circuit or equipment.
- Use non-conductive hand tools for which they are rated to perform electrical work. If they are used for voltage (or current) rating other than rated, the insulation strength of the tool breakdown and causes electric shock.
Understand Good Technique
If wires are spliced or connected to fixtures or devices haphazardly, the circuit may function for a while. But there is a good chance a wire will work its way loose, creating a dangerous condition.
Wiring correctly is relatively easy. It takes only an hour or two to learn how to make splices and connections just as solid as those made by professionals. In most cases using the right technique is faster and easier than doing something the wrong way. For example, looping a wire around a terminal screw clockwise keeps it from sliding out from under the screw head as you tighten the screw.
Use a Star Wiring Pattern
Seasoned professional installers use a Star Wiring Pattern. With star wiring, each outlet (jack) has its own individual “home run” of cabling extending back to the central distribution panel. There are three major advantages of this:
Flexibility: All changes in distribution of services can be quickly and easily made at the distribution panel. Each outlet can be treated independently of all others. (In loop, also known as “daisy chain” wiring – where a number of outlets are tied together in a series – outlets cannot be treated independently).
Isolation of Problems: When an interruption takes place (for example, a nail through a wall damages a cable) troubleshooting becomes much easier.
Quality of Signal: Each additional connection point is a potential source of interference and other problems that can cause a loss of signal quality.