Selection characteristics of busbar and conductor cross section

Selection characteristics of busbar and conductor cross section

 

When multiple rectangular busbars are used in parallel in a circuit, the distance between the busbars should not be less than the thickness of the busbar; the distance between the edges of adjacent spacers should be greater than 5mm. Spacers should be made of flame-retardant insulating materials.

6.9 When the busbars are lapped, the contact surface between the two busbars should be tightly connected, and surface-treated fasteners should be used. The bolt strength should not be less than 4.8. During the connection, there should be (flat) washers on both sides of the busbar. There should be a clear distance of more than 3mm between adjacent bolts and washers, and spring washers or lock nuts should be used on the nut side. When the bus bar is placed horizontally, the through bolts should be worn from bottom to top. In other cases, the nuts should be placed on the maintenance side, that is, the upper side, the outer side, or the right side. The bolt length should be more than 3 buckles for the nut.

6.10 The busbars of the DC panel should be installed on the top of the screen. If it is used in a single unit, it can be installed in the middle of the panel. But both ends must be fixed with insulating supports.

6.11 The phase sequence arrangement of the bus bar, when the design is not specified, meets the requirements of Table 5 (viewed from the front of the device). Under special circumstances, if the arrangement in this phase sequence will cause difficulties in busbar configuration, the provisions of this article may not be followed.

6.12 Clearance and creepage distance

Electrical clearance ZDPZ, ZDX ≥ 5.5mm, ZDXL, GGD ≥ 8mm; creepage distance ZDPZ, ZDX ≥ 8mm, ZDXL, GGD ≥ 10mm.

6.13 Selection of busbar and conductor cross section

6.13.1 The cross-sections of busbars and wires shall be selected according to the design drawings, but shall at least meet the current-carrying capacity requirements of Table 6, Table 7, Table 8, and Table 9.

 

Bus phase sequence arrangement Table 5
Category		Vertical arrangement	Horizontal arrangement	Line up
cross flow	Phase A	on	eft	far
	PhaseB	in	in	in
	PhaseC	under	right	near
	N line	Next time	Second right	Next time
	PENline	Lowermost	Most right	recent
DC	+positive electrode	on	left	far
	-negative electrode	under	right	near

 

 

 

 

 

6.13.2If the drawing does not indicate the cross section of the bus or wire, it should be selected according to the current carrying capacity and possible comprehensive factors such as stress and voltage drop. The current carrying capacity of the neutral bus is selected as half of the current carrying capacity of the phase line as shown in the drawing.