- Product overview and application scope
GCS type low-voltage withdrawable switchgear (hereinafter referred to as the device) is a low-voltage withdrawable switchgear that conforms to national conditions, has higher technical performance indicators, can adapt to the development needs of the power market and can compete with the existing imported products.
The device is suitable for power plant, petroleum, chemical, metallurgy, textile, high-rise building and other industries of power distribution system. In large power plants, petrochemical systems and other places with a high degree of automation and requiring computer interface, As a three-phase AC frequency of 50(60)Hz, rated operating voltage 380V(400V), (660V), rated current 4000A and below in the power supply system of distribution, motor centralized control, reactive power compensation for the use of low-voltage complete sets of power distribution devices.
2.Model meaning
- Standards
The design of the device meets the following criteria
IEC439-1 Low-voltage switchgear and control equipment
GB7251 Low voltage switchgear
ZBK36001 low voltage withdrawable switchgear - Main technical parameters
| Rated voltage of main circuit(V) | AC380(400)、(660) | |
| Rated voltage of auxiliary circuit(V) | AC20、380(400)、DC220 | |
| Rated frequency(Hz) | 50(60) | |
| Rated insulation voltage(V) | 660(1000) | |
| Rated current (A) | Horizontal bus | ≤4000 |
| Vertical Bus (MCC) | 1000 | |
| Bus rated short-time withstand current (kA/1s) | 50,80 | |
| Bus rated peak withstand current (kA/1s) | 105,176 | |
| Power frequency test voltage (V/1min) | Main circuit | 2500 |
| Auxiliary circuit | 1760 | |
| busbar | Three-phase four-wire system | A.B.C.PEN |
| Three-phase five-wire system | A.B.C.PEN | |
| Class of protection | IP40 | |
5.1 The main frame adopts 8MF open section steel and the two sides of section steel have Φ9.2mm mounting holes with modulus of 20mm and 100mm respectively, making the internal installation flexible and convenient.
5.2 The main frame assembly form is designed in two ways, full assembly structure and part (side cabinet and beam) welded structure, for the user to choose.
5.3 Each function room of the device is isolated from each other, and its compartment is mainly divided into function unit room, bus bar room and cable room. The function of each chamber is relatively independent.
5.4 The horizontal main bus is arranged in a flat way 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.
5.5 The design of the cable compartment makes it very convenient for the cable to go up and down.
5.6 Size series of device universal cabinet (see table below):
| high(mm) | 2200 | |||||||||
| wide(mm) | 400 | 600 | 800 | 1000 | ||||||
| deep(mm) | 800 | 1000 | 800 | 1000 | 600 | 800 | 1000 | 600 | 800 | 1000 |
- Functional unit
6.1 The module of drawer height is 160mm. Divided into 1/2 unit, 1 unit, 1 unit, 2 unit, 3 unit five size series. Unit circuit rated current 400A and below.
6.2 The drawer changes only in the height and size, and its width and depth dimensions remain unchanged. The drawers of the same functional unit have good interchangeability.
6.3 Each MCC cabinet can be installed with a maximum of 11 one-unit drawers or 22 1/2 unit drawers.
6.4 In and out of the drawer according to the current size of the use of different number of pieces of the same specification chip structure connectors.
The switch between the drawer and the cable room of unit 6.5 1/2 adopts the ZJ-2 type switch of the back plate structure.
6.6 The conversion between the unit drawer and the cable room adopts the same size rod or tube structure ZJ-1 adapter according to the current classification.
6.7 Drawer panels are clearly marked for parting, closing, testing, drawing, etc.
6.8 The drawer unit is equipped with a mechanical interlocking device.
- Device characteristics
7.1 Increase the heat capacity of the adapter to greatly reduce the additional temperature rise caused by the temperature rise of the adapter to the connector, cable head, and partition.
7.2 The separation between functional units and compartments is clear and reliable, and the failure of a certain unit will not affect the work of other units, so that the fault is limited to the minimum range.
7.3 The flat arrangement of bus bars makes the device have good dynamic and thermal stability and can withstand the impact of 80/176kA short circuit current.
7.4 MCC cabinet The number of circuit of a single cabinet is up to 22 times, fully considering the needs of large single-capacity power plants, petrochemical systems and other industries automated electric door (machine) group.
7.5 The connection between the device and the external cable is completed in the cable compartment, and the cable can be entered and exited up and down. The zero sequence current transformer is installed in the cable compartment to facilitate installation and maintenance.
7.6 In the same power distribution system, the current limiting reactor can be matched to limit the short circuit current, stabilize the bus voltage at a certain value, and partially reduce the requirements on the short circuit strength of components.
7.7 Drawer units have a sufficient number of secondary connectors (32 pairs for 1 unit and above, 20 pairs for 1/2 unit). It can meet the requirements of the number of contact points of computer interface and automatic control loop. - Installation and use
8.1 The installation of the product shall be carried out according to the installation diagram (see Figure 1 to Figure 3). The basic channel steel and bolts are provided by the customer. When connecting the main busbar, if the surface is uneven due to transportation, storage, etc., it should be smooth and then connected tightly.
8.2 When the device is installed individually or in a row, its verticality, unevenness and the deviation of the gap between cabinets shall comply with the following table.
| term | entry | Tolerance (mm) | |
| 1 | perpendicularity | 3.3 | |
| 2 | levelness | Top of two cabinets next to each other | 2 |
| Top of a row cabinet | 5 | ||
| 3 | unevenness | Two cabinets next to each other | 1 |
| Lining the sides of the cabinets | 5 | ||
| 4 | Cabinet joint | 2 | |
9.1 The device is a low-voltage power distribution cabinet that is not installed on the wall, operated on the front and maintained on both sides. Only qualified professionals can enter or open an account for operation, inspection and maintenance of the maintenance channel and door of the cabinet.
9.2 Air circuit breakers and moulded case circuit breakers after many times of division and closing, especially after short circuit division and closing, will cause local burns and produce carbon substances, so that the contact resistance increases, should be maintained and repaired according to the operating instructions of the circuit breaker and the device.
9.3 After installation and maintenance, the isolation between compartments and functional units must be strictly checked to ensure good functional separation of the device and prevent the expansion of faults.
Product completeness
The manufacturer shall provide the following documents and attachments when supplying
10.1 Packing List
10.2 Product certificate
10.3 Operating Instructions
10.4 Factory test report
10.5 Electrical drawings
10.6 Cabinet door key, operation handle and spare parts stipulated in the contract
10.7 Installation and operation instructions for major components.
Figure 1 Installation diagram of power supply and contact cabinet
Figure 2 Installation diagram of a PC cabinet
Installation diagram of power supply and contact cabinet
Figure 3 Installation diagram of the MCC cabinet