Electrical equipment installation project
First, the composition of electrical equipment installation engineering
The general electrical equipment installation project is an engineering system formed by receiving electric energy, transforming and distributing electric energy, using electric energy or distributing electric energy from receiving electric energy to electrical equipment. According to its main functions, it is divided into electrical lighting system, power system, power distribution system, etc. This engineering system based on the transmission, distribution and use of electric energy is often called strong electric engineering.
1. Electrical lighting system
An electrical device that converts electrical energy into light energy constitutes a lighting project. It includes industrial and mining enterprises production lighting and civil building lighting.
Lighting system can be divided into general lighting system, local lighting system and mixed lighting system.
The scope of the electrical lighting system generally includes: power intake - control equipment (distribution box) - distribution line - lighting (device).
Lighting system
2. Power system
The power system is the electrical energy acting on the motor to drag a variety of working equipment or electrical energy as energy for production of electrical devices, such as high, low voltage or AC, DC motors, lifting electrical devices, automatic driving devices, etc.
Power engineering usually takes a workshop or a factory building as a unit project, and its scope is: power introduction - various control equipment - distribution lines (including secondary lines) - electrical or electrical equipment wiring - grounding, debugging, etc.
3. Power distribution system
Power conversion and distribution system is a general term for electrical devices used to transform and distribute electrical energy, which is composed of two parts: power conversion equipment and power distribution equipment.
When the power transformation and distribution system is a unit project, its scope is generally from the power grid access power point to the entire project content of the output point of the distribution of electric energy, but also includes the lighting, grounding, lightning protection devices in the system.
Power distribution system
4. Lightning protection and grounding system
(1) Lightning protection device
Lightning protection device is a protection device to protect buildings, structures and equipment from lightning damage, which is usually composed of three parts: lightning connector (lightning rod, lightning protection net) or lightning arrester, connection line (lead down), grounding device.
(2) Grounding device
The grounding device consists of a grounding body and a grounding wire (ground bus).
Grounding of electrical equipment is usually divided into working grounding, protective grounding, protective zero grounding, repeated grounding and lightning protection grounding according to its function.
Lightning protection system
Second, commonly used electrical materials and equipment
Step 1: Materials
Normal distribution system is a general term for electrical devices used to transform and distribute electrical energy, which is composed of two parts: substation equipment and distribution equipment.
When the power transformation and distribution system is a unit project, its scope is generally from the power grid access power point to the entire project content of the output point of the distribution of electric energy, but also includes the lighting, grounding, lightning protection devices in the system.
2. Equipment
Commonly used electrical equipment includes: complete sets of high voltage switchgear and low voltage distribution panel, box, panel, bus support porcelain bottle brought with the equipment, combined complete box type substation, power transformer, high voltage isolation switch, high voltage circuit breaker, high voltage fuse, transformer, power capacitor, battery, etc.
Third, electrical construction drawings
1. Composition of electrical construction drawing
Electrical equipment installation engineering construction drawings generally include power distribution engineering drawings, power engineering drawings, lighting engineering drawings, external electrical engineering drawings, lightning protection grounding engineering drawings, etc. Electrical construction drawing generally consists of two parts: basic drawing and detailed drawing.
(1) Basic map
The basic drawing of the electrical construction drawing includes the drawing catalog, the construction drawing description, the system drawing, the plan, the vertical (profile) surface drawing, the control principle diagram, etc. The equipment material table also belongs to the scope of the basic drawing.
① Construction drawing description
In the electrical construction drawing, the construction description generally indicates the power supply mode, voltage level, main line laying form and the installation height of various electrical equipment not specified in the drawing, the main technical data of the project, construction and acceptance requirements and related matters.
② Main equipment material table
The equipment and materials table lists the names, models, specifications and quantities of various major equipment, pipes, wires and other equipment required by the project, which is the basis for ordering major equipment and materials.
③ Electrical system diagram
Electrical system diagram is based on the composition of electrical engineering and power distribution mode drawn, it is a summary of the entire project of the power supply and distribution line in the form of a single wire connection to express the line diagram, it does not represent the specific spatial position of electrical equipment, electrical lines.
④ Electrical plan
Electrical plans generally include power distribution engineering plans, power plans, lighting plans, weak current (telephone, broadcast) plans, outdoor electrical engineering plans, in high-rise buildings have standard floor plans, trunk layout plans, etc.
⑤ Control schematic diagram
Electrical equipment used for the control and protection of electrical equipment, generally referred to as control appliances.
The control schematic diagram is a circuit expansion diagram drawn with specified graphics and text symbols according to the working principle of the control appliance. It generally does not indicate the specific installation space location of electrical components.
① Large drawing
Details of electrical engineering are mostly large drawings of switchboard (box, board), control panel layout and some installation parts.
② Standard drawing
Standard drawing is a kind of detailed drawing with universal quality, which represents the specific graphics and detailed dimensions of a group of equipment or components, which is easy to make and install.
2. Characteristics of electrical construction drawings
Electrical construction drawings are different from mechanical engineering drawings, the general electrical plan is drawn on a simplified civil plan, in addition to some electrical system drawings, schematics and wiring diagrams. The characteristics of electrical construction drawings are:
(1) Schematic drawing is the main form of electrical construction drawing, that is, it is a diagram that indicates the relationship between the system or equipment with graphic symbols, annotated enclosures or simplified shapes.
(2) Graphic symbols, text symbols and project codes are the basic elements of electrical construction drawings.
(3) Electrical devices and electrical systems are mainly composed of electrical components and electrical connections, so electrical components and electrical connections are the main content of electrical construction drawings.
(4) Position layout method and function layout method are the two most basic layout methods in electrical construction drawings.
(5) Electrical equipment and lines do not draw their shapes and dimensions to scale in the plan, and are usually represented by legends.
