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B-5
Horizontal busbars
Up to 3200 A
Flat copper bars 10 mm thick
Distribution
Busbar calculation
Number and size of copper busbars
The bars are secured by insulated supports attached to
the framework.
The tables opposite indicate:
b
the number and size of the bars to be used,
depending on the permissible current level in the
busbars
b
the number of busbar supports for each type of
framework, depending on:
v
the size of the busbars
v
the rated short-time withstand current Icw.
For more information on busbar calculations, see page
D-23.
Permissible current (A)
No. of bars / phase
IP
y
31
IP > 31
1800
1600
1 bar, 80 x 10
2050
1850
2 bars, 50 x 10
2300
2000
2 bars, 60 x 10
2820
2500
2 bars, 80 x 10
3300
2900
2 bars, 100 x 10
Note: t
he permissible current values for the busbars are given for an ambient temperature of 35°C
around the switchboard.
Number of supports
Framework width
(mm)
Size of bars
(mm)
No. of supports
Icw
(kA rms / 1 s)
y
25
y
30
y
40
y
50
y
60
y
65
y
75
y
85
W = 650 mm
W = 650 + 150 mm
1 bar, 80 x 10
4
2 bars, 50 x 10
2
3
2 bars, 60 x 10
2 bars, 80 x 10
2 bars, 100 x 10
3
4
W = 300 mm
All sizes
1
2
W = 400 mm
All sizes
1
2
Note
: for a W = 800 mm framework, add a free support to the number of fixed supports given by
the table below.
Busbar selection
Flat busbars, L = 2000 mm
DD381229
Designation
Cat. no.
Copper bar without holes, 50 x 10
04545
Copper bar without holes, 60 x 10
04546
Copper bar without holes, 80 x 10
04548
Copper bar without holes, 100 x 10
04550
Busbar supports
Two fixed supports for 650 mm, 650 + 150 mmwide frameworks and one fixed support
for 300/400 mm wide frameworks are mandatory. If more supports are required, use
free supports.
Designation
Cat. no.
Fixed support for horizontal
bars
Width
y
80 mm
04664
Width > 80 mm
04664 + 04671
Free support (additional) for
bars
Width
y
80 mm
04662
Width > 80 mm
04662 + 04671
Icw 50 kA rms / 1 s.
DD381226
DD381225
DD381231
04664.
04662.
Joints
Designation
Cat. no.
1 joint for bars
Width 50 and 60 mm
04640
Width 80 and 100 mm
04641
Note:
when installed, at the bottom of cubicles, the busbars must be partitioned, see page B-28.
04641.
Busbar dimensions
DD381228
Type of busbars
No. of vertical modules required
Top or bottom horizontal busbars
3
Main distribution