GCS Model low-Voltage withdrawable Complete Switchgear
Designed and researched by joint design group of two ministries in accordance with requirements of industrial authority, wide electric users and design organizations, GCS model low-voltage withdrawable complete switchgear is a low-voltage withdrawable-type switch cabinet that is in compliance with situations of China, features high technical performance index, can adapt to demand of electric market development and compete with existing imported product. The device applies to power distribution system of industries such as power plant, petroleum, chemical, metallurgy, textile and high building. It is used as low-voltage complete power distribution device for power distribution, concentrated motor control and reactive power compensation of power generation and power supply system of 3-phase AC frequency 50 (60) Hz, rated operating voltage 380V (400V)/(660V) and rated current 4000A and below in large-size power plant and petrochemical system where autorotation degree is high and interface with computer is required.
Environmental Conditions for Product Use
- Ambient air temperature should be no more than +40℃ and no less than -5℃, and average temperature within 24h should be no more than +35℃.
- Altitude should be 1000m, users of high altitude region should indicate altitude upon ordering, and the product can meet requirement of user for altitude below 4000m.
- Relative humidity of ambient air should be no more than 50% under the highest temperature +40℃, and larger relative humidity is allowed under low temperature (for example: 90% under temperature of +20℃).
- he inclination from vertical plane should be no more than 5°upon installation of equipment.
- Equipment should be installed at location free from violent shock and impact, and location free from corrosion of electric appliance component.
- User can negotiate with manufacture to find out solution in case of special requirements.
- Framework adopts 8MF cold rolled section, of which two sides are configured with installation holes of modulus 20mm and 100mm, so that framework assembling is flexible and convenient.
- Lateral frame assembling mode of framework is designed as two types, full assembling structure and partial (lateral frame and cross beam) welding structure for selection by user.
- All functional compartments of switch cabinet are separated from each other, and are divided into functional unit compartment, busbar compartment and cable compartment. Functions of all compartments are relatively independent. Design of cable compartment realizes very convenient upper/lower incoming and outgoing of cable.
- Horizontal busbar adopts rear horizontal arrangement mode so as to enhance electrodynamic force resistance of busbar, which is a fundamental measure to realize high short-circuit strength of main circuit.
- Modulus of drawer height is 160mm。 Drawer change is limited to change of height dimension only, while its width and depth dimension remain unchanged。 Drawer of identical functional units features excellent interchangeability。 Rated current of unit circuit is 630A and below。
- Drawer panel features prominent marking of open, close, test and drawn positions. Drawer unit features mechanical interlock unit.
- Incoming/outgoing line of drawer should adopt different number of plug-in components of slice architecture of the same specification as per electric current size. The switchover between unit drawer and cable compartment should adopt identical size of bar type or tubular type structure ZJ-1 switchover parts as per classification of current. The switchover between 1/2 unit drawer and cable compartment should adopt backboard structure ZJ-2 switchover parts
Main Circuit Program
The main circuit program of device totals 33 groups and 118 specifications (see the following table), excluding program and specification derived from change of control and protection of auxiliary circuit, including demand of power generation, power supply/consumption and other power user, the rated operating current is 4000A and applies to power distribution transformer of 2500kVA and below 2500kVA. Furthermore, capacitor compensation cabinet has been designed to adapt to demand of power supply and consumption to enhance power factor; and reactor cabinet has been designed with consideration of demand of comprehensive investment.
Auxiliary Circuit Program
Auxiliary circuit program of DC operation section is mainly used for normal control mode of low-voltage plant (station) service of power plant transformer substation and generator unit low-voltage station service, operating (backup) power supply incoming line, power supply feeder and motor feeder. Auxiliary program of AC operation section is mainly used for low-voltage system of substation of industrial and mining enterprises and high building. Auxiliary circuit program is designed on the basis of main circuit program branch power supply incoming line, feeder (PC) and functional unit incoming line of motor feeder (MCC) operation and control.
Selection of Electric Components
Main electric components in cabinet adopt advanced products of China featuring high breaking capability, and imported technology products, and meet requirements on high performance of device。 Such as: circuit breaker adopts F series of CM1, ME, AH, DZ20, TM30 and ABB; contactor adopts CJ20, CJX and LC1, etc; and thermal relay adopts JR16, 3UA and LRA-D, etc。
These components feature characteristics such as excellent performance, compact structure, light weight, short flashover or no flashover and high technical performance index, and meets requirements of this device.
After arrival of product at place of goods receiving, firstly it is necessary to check whether package is complete and free from damage, and inform relevant department to make commercial record in case of discovery of problem, analyze the root-cause jointly, sign and deal with problems coming after.
It is necessary to place products that will not be packed immediately at appropriate location in accordance with normal usage conditions or rules on temporary safekeeping of electric equipment.
Installation of products should be in compliance with following diagram, and user should prepare foundation channel steel and bolt in the case of adoption of bolt fixture, in case of uneven surface caused due to reasons such as transportation and storage, it is necessary to connect and fasten after flattening during connection of main busbar. For installation of main busbar, it is necessary to repair, flatten and clean faying surface, apply neutral Vaseline or adopt other measures, then fasten with bolt.
Inspection And Test After Installation of Product But Before Putting Product Into Service
- Inspect whether cabinet surface paint or other coverage material (such as plastic spraying) is damaged, whether interior of cabinet is dry and clean.
- Whether operating mechanism of electric component is flexible, jamming or extremely large operating force is not allowed.
- Whether on/off of main/auxiliary contact of main electric appliance is reliable and accurate.
- Pulling/pushing of drawer or withdrawable-type mechanism should be flexible and easy and should be free from jamming and collision.
- The center line of moving/fixed contact of drawer or withdrawable-type mechanism should be consistent, contacting of contact should be tight, insertion depth of main/auxiliary contact should be in compliance with requirement, mechanical interlock or electric interlock device should act correctly, locking or releasing should be reliable.
- Scale setting of instrument and transformation ratio polarity of transformer should be correct.
- Core specification of fuse should be in compliance with requirements of engineering design.
- Fixed value and setting of relay protection should be correct, and activation should be reliable.
- Insulation resistance should be no less than 1MΩ when measured by using 1000 megohmmeter.
- Connection of all busbars should be good, installation of insulation support component, installation component and other accessories should be firm and reliable.
Items To Be Noticed For Usage
- GCS series of cabinet is low-voltage power distribution cabinet featuring free standing, frontal operation and double sides repair, only professionals who has been appraised as eligible can enter or open the access passage and door of cabinet for operation, inspection and repair.
- After air circuit breaker and plastic casing circuit breaker experience numerous times of make/break, especially short-circuit make/break, partial area of contact will be burnt and produce carbon related substance, thus increasing contact resistance, it is necessary to maintain, inspect and repair as per usage instruction manual of circuit breaker.
- After installation and repair, it is required to inspect strictly that the isolation conditions between all compartments and between functional units have been resumed, so as to assure functional compartmentation of the equipment and prevent expansion of malfunction.
Manufacturer should provide the following documents and attachments upon product supply:
2.Certificate of conformity
3.Usage instruction manual;
4.Delivery inspection report;
5.Related electric drawing;
6.Key to cabinet door, operating handle and spare parts indicated in contract.