low-voltage cabinet is mainly composed of the following parts:
1. Cabinet
The functions of the cabinet include independent support, component fixation, withstanding electric power, withstanding vibrations such as transportation earthquakes, etc.;
cabinet has angle steel welded type, Steel plate bending splicing type and prefabricated profile splicing type. The mainstream is prefabricated profile splicing type. The profiles are mainly C and reinforced C profiles. They are composed of beams, corner parts, etc. using self-operating screws. Aluminum tees and other forms can be used to maintain the cabinet body. Neatly spliced to achieve quick installation, anti-eddy current and other functions.
2. Insulation parts
For busbar , whether it is a horizontal busbar or a vertical busbar, it is necessary to maintain an electrical gap and withstand electric power; this requires that the busbar must have insulation and support functions, and must have sufficient strength to withstand the short circuit of the busbar. The huge electric power, especially between phases, is arranged in three phases on the same plane. Phase B bears the greatest force, so the insulation strength needs to be high enough.
Insulation parts mainly include busbar clamps, functional boards and insulators , etc. The busbar clamps, as the name suggests, clamp the busbar in the insulating parts, which not only ensures the electrical clearance but also plays a supporting role. The busbar clamp has three phases (four phases) in one, using SMC
( DMC) material, the upper and lower meshes are fixed on the metal mounting plate through bolts; the combined busbar clamp is a tooth-shaped comb-shaped busbar clamp, which is buckled on the mounting plate, and the busbar is fixed between the upper and lower busbar clamps using bolts Connect the two busbar clamps. The combined type is not limited by the width of the copper bar, and the width can be from 30 to 200mm. For example, the busbar clamp of cabinet B can be used for 5x200mm copper bar. You only need to adjust the bolt length according to the width. The comb busbar clamp is made of reinforced nylon material. , high strength and strong resistance to electric force. The
function board is used in drawer cabinets. Its main functions include busbar positioning support, drawer primary plug-in guide, and protection level IP2X to prevent fingers from accidentally touching live objects. The functional board is designed according to the modularization, and the modular unit combination is made of SMC material and ABS material, which has high strength and limits arc.
Low-voltage insulators have different heights of 40-60mm. The material is generally BMC. There are cylindrical and hexagonal shapes. They are mainly used for N row supports and some connecting row supports. Hexagonal insulators are also used to support the main busbar, such as MB301M marine switch cabinet. The busbar system uses 5mm thick copper bars. Multiple pieces of busbars pass through all copper bars through threaded rods. The hexagonal insulators on both sides are tightened and fixed. Steel plates on both sides of the busbar system Clamping, extremely high strength, strong resistance to short-circuit current , and anti-vibration.
3. Busbar system
busbar system, carrying the rated current of , is assigned to the outlets of each functional unit. There are horizontal busbars and vertical busbars. The horizontal busbars are placed at the back of the cabinet. Domestic customers tend to place the horizontal busbars at the top of the cabinet. , easy to connect, but not conducive to current distribution. Placing it behind the cabinet is more conducive to current distribution and reduces the use of copper bars. The horizontal busbar shunts the current upward and downward at the back of the cabinet. The vertical busbar only needs to carry half of the current, while the top of the cabinet bus, the vertical bus needs to carry all the current, there are many copper rows, and some even use double sets of vertical rows.
You may think that if the horizontal busbar is behind the cabinet, it can only be exited from the side, adding a separate outlet compartment and increasing the width. In fact, this is not the case. The horizontal busbar can also be exited from the rear behind the cabinet.
4. Functional unit
circuit breaker fixed separation, drawer and other functional units are combined into power distribution, motor control and other solutions, reactive power compensation and other solutions.
The drawer needs to be closed to ensure safety. It uses a primary connector to connect to the vertical busbar. The double-clamp contact structure can reduce contact wear and does not require operating mechanisms such as rocking in. The plug-in circuit breaker is used to fix the partition cabinet. It is easy to install and reliable in connection. It can also be removed for maintenance when necessary.
5. Cover plate, door panel
cover plate door panel protects the safety of operators, prevents arcs, and prevents small animals from entering. The high protection level switch cabinet can also prevent the entry of moist air such as rain and salt spray.
