Summary

GGD AC low-voltage distribution cabinet is applicable to the distribution system with AC 50Hz, rated working voltage of 380V and rated working current of 5000A for power plants, substations, industrial and mining enterprises and other power users. It is used for power conversion, distribution and control of power, lighting and distribution equipment.

The product has the characteristics of high breaking capacity, good dynamic and thermal stability, flexible electrical scheme, convenient combination, strong practicability, novel structure and high protection grade. It can be used as an updated product of low-voltage switchgear.

GGD AC low-voltage distribution cabinet complies with iec439 low voltage switchgear and control equipment, GB7251 low voltage switchgear and other standards.

 Model meaning

Normal use environment

◆ the ambient air temperature shall not be higher than + 40 ℃ and not lower than - 5 ℃. The average temperature within 24h shall not be higher than + 35 ℃.

◆ for indoor installation and use, the altitude of the place of use shall not exceed 2000m.

◆ the relative humidity of the surrounding air shall not exceed 50% when the maximum temperature is + 4O ℃, and higher relative humidity is allowed at lower temperature. (for example, 90% at + 20 ℃) the effect of accidental condensation due to temperature change shall be considered.

◆ when the equipment is installed, the inclination with the vertical plane shall not exceed 5%.

◆ the equipment shall be installed in the place without violent vibration and impact, and in the place where the electrical components are not enough to be corroded.

◆ negotiate with the manufacturer when the user has special requirements.

Electrical performance

Basic electrical parameters

◆ main circuit scheme

The main circuit of GGD cabinet is designed with 129 schemes and 298 specifications in total (excluding the schemes and specifications derived from the function change of auxiliary circuit and the change of control voltage). Including: 49 schemes and 123 specifications of ggd1 type

GGD2 53 schemes 107 specifications ggd3 27 schemes 68 specifications

The main circuit scheme is selected after soliciting the opinions of the majority of design and user departments, which increases the scheme required by the power plant. The rated current is increased to 320oa, which is suitable for distribution transformers of 2000kVA and below. In addition, in order to meet the needs of reactive power compensation, ggj1-ggj2 capacitor compensation cabinet is designed. Its main circuit has 4 schemes and a total of 12 specifications.

◆ auxiliary circuit scheme

The design of auxiliary circuit is divided into power supply scheme and power plant scheme. There is enough space in GGD cabinet to install secondary components.

◆ selection of electrical components

◇ GGD cabinet mainly adopts domestic excellent electrical components that can be mass produced, such as me, DW15, dw17, DW45, CM1, NM1, etc. at the same time, according to the principle of economy and rationality, some available old products such as DZ20 are retained on the premise of full consideration of feasibility. Do not use obsolete products.

◇ hd13bx and hs13bx rotary operated knife switches are special components designed to meet the needs of the special structure of GGD cabinet. They change the operation mode of the mechanism and retain the advantages of old products. They are a practical electrical component.

◇ if the design department selects electrical components with better performance and according to the needs of users, because the GGD cabinet has good installation flexibility, it generally will not cause difficulties in manufacturing and installation due to the renewal of electrical components.

◇ in order to further improve the dynamic stability of the main circuit, ZMJ combined bus clamp and insulating support special for GGD cabinet are equipped. The bus clamp is made of high-strength and flame-retardant PPO alloy material, which has high insulation strength, good self extinguishing performance and special structure. It can be easily combined into single bus clamp or double bus clamp by adjusting the building block. When the insulation is supported, the sleeve molded structure has low cost and high strength, which solves the defect of insufficient creepage distance of old products.

Structure introduction

◆ the cabinet body of GGD AC low-voltage distribution cabinet adopts the type of general cabinet, and the frame is locally welded and assembled with 8MF cold-formed section steel. The frame parts and special supporting parts are supplied by the designated manufacturer of section steel, so as to ensure the accuracy and quality of the cabinet body.

The parts of the general cabinet are designed according to the module principle, and there are 20 die mounting holes. The general coefficient is high, which can enable the factory to realize pre production, which not only shortens the production cycle, but also improves the work efficiency.

◆ heat dissipation during cabinet operation shall be fully considered in the design of GGD cabinet. There are different numbers of heat dissipation slot holes at the upper and lower ends of the cabinet. When the electrical components in the cabinet heat up, the heat rises and is discharged through the upper slot hole, and the cold air is continuously supplemented into the cabinet from the lower slot hole, so that the sealed cabinet body forms a natural air duct from bottom to top to achieve the purpose of heat dissipation. According to the requirements of modern industrial product modeling design, GGD cabinet adopts the golden section ratio method to design the appearance of the cabinet and the division size of each part, so as to make the whole cabinet beautiful and fresh.

◆ the cabinet door is connected to the frame with a rotating shaft movable ammonium chain, which is convenient for installation and disassembly. A mountain shaped rubber and plastic strip is embedded at the folding edge of the door. When closing the door, the strip between the door and the frame has a certain compression stroke, which can prevent the direct collision between the door and the cabinet body and improve the protection grade of the door.

◆ the instrument door with electrical components is connected with the frame with multi strand soft copper wire, and the mounting parts in the cabinet are connected with the cabinet frame with knurled screws. The whole cabinet forms a complete grounding protection circuit.

◆ the cabinet surface is sprayed with plastic, with strong adhesion and good texture. The whole cabinet is in matte color, avoiding dazzling effect and creating a more comfortable visual environment for the personnel on duty.

◆ the top cover of the cabinet can be removed when necessary to facilitate the assembly and adjustment of the main bus on site. Lifting rings are installed at the four corners of the cabinet top for lifting and shipping.

◆ the protection grade of the cabinet is IP30. Users can also choose between IP20 and IP40 according to the requirements of the service environment.

The outline and installation dimensions are shown in Figure 1 and Figure 2.