What is an electrical system
The electrical system is a combination of electrical components that are connected to carry out some operations. The electrical power system is a composite system of generation, transmission and distribution system. A generator will produce electricity and it is transmitted to the transformer by using cables and the transformer will convert the electricity from low voltage to high voltage. High voltage electricity can be transmitted to long-distance more efficiently. Transmission lines will carry the electricity to the substation and the substation has transformers that can convert the high voltage power to low voltage power and from the substation, the electricity will be transmitted to the consumers.
Electrical and electronic symbols
The type of electrical service is determined by the public utility supplying electrical power. Mostly electrical utilities produce and distribute alternating current power to their consumers. The typical residential service is 120/240V single-phase AC power. Electrical power reaches the home or building through service entrance equipment and this power will be controlled and then it will be distributed to the branch circuits. The loads are supplied by the branch circuits. The electrical system in a building has many components such as wires, fuses, circuit breakers, switches, etc. Mostly the electrical system for a residence industrial and commercial system uses a similar component in the same way.
What are the parts of an electrical system and electrical system in a house
Service entrance has the service drop, service entrance cables, watt-hour meter, service disconnecting means, and a grounding conductor.
Service drop – The utility company will install the service drop and the conductors of the service drop are connected to the building, and they are known as service lateral conductors. The number of conductors depends on the type of distribution system.
Service entrance cable – The service entrance cables continues from the point of attachment to the building through the watt-hour meter. No need for underground service, when you install service entrance cables or conductors. The reason for this is the service lateral conductors that run from street mains to the building are terminated by the power company directly at the meter base.
Watt-hour meter – it is the meter that shows the amount of energy used by the consumer. The location of this meter is specified by the utility company. Mostly the meter is installed between the service drop or service lateral and the service disconnecting means.
Service disconnecting means – The disconnecting means could be a circuit breaker, switches, or fuses. Usually, the service disconnecting device is operated manually, it must provide a visual means to tell whether it’s in the open or closed position. This device will be located in an accessible area near the service entrance. The circuit breaker or fuse can prevent excessive current and it also prevents the over-supply of electrical power to the service entrance.
Grounding conductor – It is a low resistance conductor, which is connected between the ground and the identified neutral wire of the alternating current service conductors. The color code for the neutral wire would be white or natural gray and the grounding conductor is either a bare conductor or green in color.
Feeder cable – The electrical system is extended by the feeder conductors, the feeder cable or conductors between the load side of the service disconnect and the branch circuit panel board. Between these two points, there won’t be any load.
Distribution panel board – At the distribution panelboard, the branched circuits are tapped off the feeders. Such panel boards usually have fuses or circuit breaker which protects the branch circuit. Sometimes branch circuits would be protected by both fuses and circuit breakers.
Subpanel feeder cable – This is an extension of the main feeder, the conductors in the feeder cable must be protected by a circuit breaker or fuses in the main distribution panel.
Branch circuit cables – The above figure shows four branch circuit cables extending from the distribution panel board. So only four of the 15 branch circuits are supplying loads. These four branch circuits are 120v circuits that supply a duplex receptacle, or convenience outlet, and a lamp that is controlled by a switch. Only single loads are shown in each circuit, but this circuit could supply more than one load.