A single-line power supply diagram is designed to make it possible to understand how the main components of the circuit are located and what is the sequence of their connection. At the same time, the main markings and types of electrical equipment, their manufacturer and some parameters are most often reflected on single-line diagrams.
Single-line electric power supply circuit serves for clarity and allows you to understand the general principle of the circuit. As a rule, such a scheme is necessary at the first stages of working with equipment.
According to GOST for the preparation of design documentation for the installation and commissioning of electrical equipment, each diagram must have a stamp, while each switchgear has its own parameters, which must be indicated on the drawing. These parameters include: COS φ, type of cable used, power and current. If the scheme is carried out with electrical cabinets, then their location should be indicated on a single-line diagram, in addition, to control modern disconnectors in switchgear, todayremote control. It can be displayed in the control panel or remain close to the drive, while the button is displayed separately from the disconnector. The single-line power supply diagram should also reflect their location.
The length of the cables and the scheme of their layout is reflected with an accuracy of one meter. Thus, the contractor understands the big picture and evaluates the amount of work ahead.
The electrical diagram must contain the type and location of metering devices, as well as the loss of electricity during transmission through power lines. The scheme and data are secured by the signature of the engineer for the development of this document.
Before a single-line power supply scheme for a residential building goes into production, it goes through a series of approvals. At the same time, only a specialist with a permit from the SRO can compile it. The company for the production of these schemes must be a member of the SRO. If a sample circuit is created without the necessary approval, then it cannot be considered by the competent authorities.
Implementation of a single-line circuit is a crucial step; how it is composed depends on whether energy will be spent economically. For example, it is known that the total load is inductive in nature, since motors, power supplies and transformers often act as consumers. Thus, COS φ decreases, resulting in a huge power consumption. To avoid this, a single-line power supply is carried out with capacitor banks. SoSince the reactance vectors of the coil and capacitor are oppositely directed, they compensate each other, thereby excluding their influence on power, COS φ increases, and production saves money.
However, a single-line power supply circuit can only include capacitor banks when it is advisable. For example, to provide electricity to small areas, this approach is not rational, since active resistance mainly prevails, but if there are large plants, factories or any other production in the district, then capacitor banks are simply necessary.
Electrical designers must carefully study the place where the replacement of power circuits is planned, and draw the right conclusions.
