GCS Low voltage withdrawable switch Cabinet

GCS devices are suitable for distribution systems in industries such as power plants, petroleum, chemical, metallurgical, textile, and high-rise buildings. In places with high automation requirements and computer interfaces such as large power plants and petrochemical systems, low-voltage complete distribution devices are used for distribution, centralized control of motors, and reactive power compensation in power generation and supply systems with a three-phase AC frequency of 50 (60) Hz, rated working voltage of 380V (400V), (660V), and rated current of 4000A and below.

Performance index 

The design of the device meets the following standards

IEC439-1     Low Voltage Switchgear and Control Equipment

GB7251       Low Voltage Complete Switchgear

ZBK36001   Low-voltage withdrawable complete switchgear

Basic electrical parameters

Main structure

1. The main frame is made of 8MF type open section steel. The two sides of the section steel have installation holes with modules of 20mm, l00mm and o9.2mm respectively, making the internal installation flexible and convenient.

2. The main frame assembly is designed in two forms, full assembly structure and part (side frame and beam) welded structure, for users to choose.

3. The functional rooms of the device are isolated from each other, and the compartments are divided into functional unit rooms, busbar rooms and cable rooms. The function of each chamber is relatively independent.

4. The horizontal main bus line is arranged in flat mode behind the cabinet to enhance the ability of the bus to resist electric power, which is the basic measure to make the main circuit of the device have high short-circuit strength.

5. The design of cable compartment makes it very convenient for the cable to go up and down

6. Size series of the universal cabinet (see the table below Unit: mm):

Major electrical component

The selection principle of the main electrical components based on the introduction of technology, domestic can be a series of mass production, but also to meet the high performance requirements of the device.

1. Power supply and feeder unit circuit breakers mainly select AH series. Other more advanced M series produced by Schneider and F series produced by ABB can also be selected. AH circuit breaker has the characteristics of good performance, compact structure, light weight and strong series. The price is relatively low. Easy to maintain and use, the performance indicators can meet the requirements of the device.

2 Extraction unit (electric mechanism unit, part of the Buddhas single) circuit breaker main wash CM1, TG, TM30 series tidal shell circuit breaker. Some of them are NZM-100 series produced by MOELLER Company. These switches have the characteristics of good performance, compact structure, short flying arc or no flying arc, and high technical and economic index, which can meet the requirements of this device

3. Isolation switch and fuse type isolation switch choose Q series. The series has high reliability, strong breaking ability, and can realize mechanical interlocking.

4. Fuse main NT series

5. Ac contactor B series, LC1-D series

Device characteristics

1. Improve the heat capacity of the adapter to greatly reduce the additional temperature rise brought by the temperature rise of the adapter to the connector, cable end and partition board. 

2. The separation between functional units and compartments is clear and reliable, so that the failure of one unit will not affect the work of other units, so that the fault is limited to the minimum range. 

3. The flat busbar arrangement makes the dynamic and thermal stability of the device good, can withstand the impact of 80/176kA short circuit current

4. The number of circuits in a single MCC cabinet is up to 22 times, fully considering the needs of large single capacity power generation, petrochemical system and other industries of automatic electric door (machine) group 

5. The connection between the device and the external cable is completed in the cable compartment, and the cable can be up and down. The current transformer is installed in the cable compartment for convenient installation and maintenance. 

6. In the same power distribution system, the current limiting reactor can be matched to limit the short circuit current, stabilize the bus voltage in a certain value, and partially reduce the requirements on the smoke circuit strength of components. The extraction unit has a sufficient number of secondary connectors (32 pairs for 1 unit and above, 2 pairs for 1/2 unit) to meet the requirements of the number of contact points of the computer interface and automatic circuit

Auxiliary circuit

The design of the auxiliary circuit diagram conforms to the technical regulations of the design of thermal Power Plants and other relevant technical regulations. It is suitable for the power system of low-voltage plant (institute) in power plants and substations, and the low-voltage distribution system in factories and mining enterprises and high-rise buildings.

The auxiliary circuit scheme is designed according to the main circuit scheme, which can be divided into power supply line, feed line (PC) and motor feed line (MCC).

Installation and use

After the product arrives at the receiving place, it shall first check whether the package is complete and undamaged. If any problem is found, it shall timely notify the relevant department of the contract to make business records, jointly analyze the reasons, and prepare the visa and post-processing. For products that are not installed immediately, they should be placed in appropriate places and kept properly according to normal service conditions and temporary storage regulations of electrical equipment.

1. The installation of the product shall be carried out in accordance with the installation diagram (see the attached figure). The base steel and the screw fixed method shall be prepared by the user. When connecting the main busbar, if the surface is uneven due to transportation, storage and other reasons, it should be leveled before connecting and fastening.

2. When the device is installed separately or in a row, the verticality, the unevenness of the cabinet surface and the deviation of the gap between the cabinets shall comply with the provisions in the following table

3. Inspection and inspection of products after installation and before operation

(1) Check whether the cabinet paint or other covering materials (such as spray) are damaged, and whether the cabinet is dry and clean

(2). Whether the operating mechanism of electrical components is flexible and should not be stuck or operate with too much force.

(3) Whether the main and auxiliary contacts of the main electrical appliances are reliable and accurate.

(4) Drawer or pull-out mechanism should be flexible, light, no jamming and collision phenomenon.

(5). The center of the moving head and the static head of the pumping or extraction structure should be consistent, and the head contact should be close. The insertion depth of the main and head should meet the requirements. Mechanical interlocking or electrical

The interlocking device shall operate correctly, and the lock or release shall be reliable.

(6) The extraction of the same size should be convenient to exchange, no jamming and collision phenomenon

(7) The ground contact between pumping and cabinet body should be connected tightly. When pumping and pushing into, the ground contact of pumping is connected first than the main contact, and the ground contact is disconnected after the main contact when pulling out

(8) The calibration of the instrument, the ratio and polarity of the transformer should be correct.

(9) The core specification of the fuse shall meet the requirements of engineering design.

(10). The rating and setting of protection shall be correct and the operation shall be reliable

(11) Insulation resistance value shall not be less than 1MQ with 1000V megohm meter

(12). The connection of all bus bars shall be good, and the installation of insulation supporting parts, mounting parts and other accessories shall be firm and reliable.

4. Use precautions

(1) The device is the maintenance channel and door of the low-voltage distribution cabinet without wall installation, positive operation and double-sided maintenance. Only qualified professionals can enter or open it for operation, inspection and maintenance.

(2). Air circuit breaker and moulded case circuit breaker after many times of division and closing, especially after short circuit division and closing, will make the head local burn and produce carbon substances, so that the contact resistance increases, should be maintained and repaired according to the circuit breaker instruction manual.

(3) After installation and maintenance, it is necessary to strictly check the isolation status between the compartments and functional units to ensure good functional separation of the device and prevent fault expansion.