1. Overview

 GGD type AC low-voltage distribution cabinet switchgear is suitable for power users such as power plants, substations, industrial and mining enterprises, etc. as power, lighting and distribution equipment in power distribution systems with AC 50Hz, rated working voltage 380V, and rated current up to 3150A. It is used for the conversion, distribution and control of electrical energy.

GGD type AC low-voltage distribution cabinet has the characteristics of high breaking capacity, good stability, flexible power scheme, convenient combination, strong practicability, ovel structure and high protection level.

 GGD type AC low-voltage distribution cabinet complies with IEC439 《Low-voltage complete switchgear and control equipment》GB7251.1 《Low-voltage complete switchgear》 and other standards.

2. Model meaning

 G: AC low-voltage power distribution cabinet G: Fixed installation and fixed wiring of electrical components D: Electric power cabinet

3. Environmental conditions of use

①. The ambient air temperature should not be higher than +40℃ and not lower than -5℃, and its average temperature within 24 hours should not be higher than +35℃.②. For indoor installation and use, the altitude of the use location does not exceed 2000m;

③ The relative humidity of the surrounding air does not exceed 50% when the maximum temperature is +40°C. A larger relative temperature is allowed at lower temperatures. (For example, 90% at +20°C) Consideration should be given to the possible effects of condensation due to temperature changes.

④. When installing the equipment, the inclination with the vertical plane shall not exceed 5%.

⑤. The equipment should be installed in a place without severe vibration and impact, or in a place where electrical components are not corroded.

⑥When users have special requirements, they can negotiate with the manufacturer.

4、Electrical properties

①.technical parameter

②Main circuit scheme

The main circuit of the GGD cabinet has been designed with 129 plans and a total of 298 specifications (excluding plans and specifications derived from changes in the function of the auxiliary circuit and changes in the control voltage).

Among them, there are 49 plans and 123 specifications for GGD1 type

GGD2 type 53 plans 107 specifications

GGD3 type 27 plans 68 specifications

The main circuit plan was compiled after soliciting opinions from the design and usage departments. Added options required for power plants. The rated current is increased to 3150A, which is suitable for distribution transformers of 2000KVA and below.

In addition, GGJ1 and GGJ2 capacitor compensation cabinets are designed to meet the needs of reactive power compensation, with 4 main circuit schemes and a total of 12 specifications.

 ③Auxiliary circuit solution

The design of the auxiliary circuit is divided into two parts: the power supply plan and the power plant plan. There is enough space in the GGD cabinet to install secondary components. At the same time, NLS has also developed a special LMZ3D current transformer to meet the needs of power plants and special users when attaching relay protection.

 ④. Main busbar

Taking into account the price ratio and the feasibility of replacing copper with aluminum. When the rated current is 1500A, double copper busbars are used. AC low-voltage power distribution cabinets comply with standards such as IEC439 "Low-voltage complete switchgear and control" and GB7251.1 "Low-voltage complete switchgear".

The overlapping surfaces of the busbars are treated with tin enameling process.

 ⑤.Selection of electrical components

 a. The main components of the GGD cabinet are ME, DW15, and DZ20 circuit breakers, as well as electrical appliances developed and produced with introduced technology in recent years. Products such as CW1, CM1, M, and F series do not use obsolete products.

 b.HD13BX and HS13BX rotary operating knife switches are special components designed by NLS to meet the unique structural needs of GGD cabinets. It changes the operating mode of the mechanism and retains the advantages of old products. It is a new practical electrical component. .

 c. If the design department selects new electrical components with more advanced performance based on user needs, since the GGD cabinet has good installation flexibility, there will generally be no manufacturing and installation difficulties caused by updating electrical components.

 In order to further improve the dynamic stability of the main circuit, NLS designed the ZMJ type combined busbar clamp and insulation support specifically for the GGD cabinet. The busbar clamp is thermoplastically formed from high-strength, high-flame-retardant PPO alloy material. It has high insulation strength, good self-extinguishing performance, and unique structure. It can be easily combined into a single busbar or double busbar clamp by simply adjusting the building blocks. The insulation support is a sleeve-type molded structure, which is low in body and high in strength, and solves the problem of insufficient arc creeping distance of old products.

5. Structural characteristics

①. The cabinet of the GGD type AC low-voltage distribution switchgear adopts the form of a general cabinet. The frame is partially welded with 8MF cold-formed steel. The frame parts and special supporting parts are produced and supplied by our company to ensure the accuracy of the cabinet. and quality. The parts of the universal cabinet are designed according to the modular principle, and have 20 module mounting holes, so the universal coefficient is high. It enables companies to achieve pre-production. It not only shortens the production and manufacturing cycle, but also improves work efficiency.

②. When designing the GGD cabinet, the heat dissipation problem during cabinet operation is fully considered. There are different numbers of heat dissipation slots 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 slots, while cold air is continuously replenished into the cabinet through the lower slots, making the sealed cabinet self-contained. A natural ventilation channel is formed from bottom to top to achieve the purpose of heat dissipation.

③. In accordance with the requirements of modern industrial product design, the GGD cabinet adopts the method of golden ratio to design the shape of the cabinet and the division size of each part, making the whole cabinet beautiful and elegant.

④. The cabinet door is connected to the cabinet frame with a rotating shaft-type movable hinge, making it easy to install and disassemble. There is a mountain-shaped sealing strip embedded in the folded edge of the door. When closing the door, the sealing strip between the door and the frame has a certain compression stroke, which can prevent direct collision between the door and the cabinet and also improves the door's protection level.

⑤ The instrument door equipped with electrical components is connected to the frame with multiple strands of soft copper wire. The installation parts in the cabinet are connected to the frame with knurled washers, and the entire cabinet forms a complete grounding protection system.

⑥ The surface of the cabinet is treated with high-voltage electrostatic spraying process. It has strong adhesion and good texture. The entire cabinet is matt in color, which avoids glare effects and creates a more comfortable visual environment for the personnel on duty.

⑦. The top cover of the cabinet can be removed when needed to facilitate the assembly and adjustment of the main busbar on site. The four corners of the cabinet top are equipped with lifting rings for lifting and shipping.

⑧. The protection level of the cabinet is IP30, and users can also choose between IP20 and IP40 according to the requirements of the use environment.

6.Installation and use

When the product arrives at the delivery location, you should first check whether the packaging is complete and intact. If any problems are found, notify the relevant departments to find out the cause in a timely manner. Products that are not installed immediately should be placed in an appropriate place according to the normal conditions of use.

①. Product installation

The installation of the product should be carried out according to the installation diagram. The basic channel steel and bolts are provided by the user. When the main busbar is installed, the overlapping surface should be repaired and smoothed, treated dry, coated with neutral Vaseline or other measures should be taken, and then the bolts should be firm.

②. The following items must be inspected and tested before the product is put into operation after installation.

A. Check whether the paint on the surface of the cabinet is peeling off and whether the inside of the cabinet is dry and clean.

B. Whether the operating mechanism of the electrical components is flexible and there should be no jamming or excessive operating force.

C. Whether the main electrical components are connected reliably and accurately, and whether the auxiliary contacts are connected reliably and accurately.

D. Whether the instrument indication and transformer changes and polarity are correct.

E. Whether the busbar connection is good, and whether the insulation supports, installation parts and accessories are installed firmly and reliably.

F. Whether the auxiliary contacts meet the requirements, whether the core specifications of the fuse are correct, whether the setting value of the circuit breaker meets the design requirements, and whether the action is accurate.

G. Whether the contacts of the circuit meet the requirements of the electrical schematic diagram.

H. Whether the protection circuit system meets the requirements.

I. Use a 500-volt megohmmeter to measure the insulation resistance and it shall not be less than 1 megohm.

③. Precautions for use

A. This product is not installed against the wall, operates on one side (double side), and maintains low-voltage distribution cabinets on both sides. Product maintenance channels and cabinet doors must be entered or opened by qualified professionals for operation, inspection and maintenance.

B. After the air circuit breaker is closed and opened many times, the main contacts will be partially burned and carbon substances will be produced, which will increase the contact resistance. The air circuit breaker should be maintained and inspected regularly according to its operating instructions .

7. Product completeness

The manufacturer shall provide the following parts and accessories when supplying goods:

a. Packing list

b. Product certificate

c.Instruction manual

d.Factory test report

e. Relevant electrical drawings

f. Cabinet door keys, operating handles and spare parts specified in the contract.

8. Ordering Instructions

Users should provide the following information when ordering:

①. The full model of the product (including main circuit plan number and auxiliary circuit plan number).

② Main circuit system combination sequence diagram.

③. Electrical schematic diagram of auxiliary circuit.

④. List of components in the cabinet.

⑤. Other special requirements that are inconsistent with the normal use conditions of the product.