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Fixed Phase and Earthing Points EaS Cables Phase Connecting Elements Earth Connecting Elements Earthing Sticks EaS Devices, Short-Circuiting Bars
4. Carry out Earthing and Short-Circuiting – EaS Devices

Cable cross-section: Current carrying capacity of copper short-circuiting cables for
For short-circuiting cables of our threepole earthing and short-circuiting use in a.c. and three-phase installations
devices with cross-sections of 50 mm and higher, the cross-section of the kA
2
earthing cable can be reduced according to the following table. 100
These earthing and short-circuiting devices with reduced earthing cable
cross-sections can be used for all non-solidly earthed neutral systems (e.g. I ‘‘ k 50 42.0 kA
compensated systems with impedance neutral earthing). For solidly 30 33.5 kA
26.5 kA
earthed neutral systems, the earthing and short-circuiting cables must 19.5 kA A = 150 mm
have the same cross-sections. 14.0 kA A = 120 mm 2 2
The current carrying capacity of the short-circuiting cable and the short-cir- 10.0 kA A = 70 mm 2
A = 95 mm
cuiting bar depends on the material, the cross-section (A) and the 10 7.0 kA A = 50 mm 2
short-circuit time (Tk). A = 35 mm 2
Calculations were based on the most critical case, i.e. an off-generator 5 4.5 kA A = 25 mm 2
short circuit (μ = 1) and a maximum d.c. components ( χ = 1.8) with Ik“ 3 A = 16 mm 2
being the maximum initial short-circuit alternating current, which, accord- 2
ing to DIN VDE 0102, is equal to the permanent short-circuit current Ik and
the breaking current Ia: 1
0.01 0.03 0.05 0.1 0.3 0.5 1 3 5 10 s
Ik“ = Ik = Ia T
k
The diagrams or the table help to determine the required cable or busbar Initial cable temperature 20 °C Where:
cross-sections of short-circuiting devices according to the short-circuit A Cable cross-section in mm 2
current and the short-circuit time of an installation. Final cable temperature 250 °C Ik“ Maximum initial short-circuit alternating
A = 5.07 Ik“ √ Tk for Tk ≥ 0.5 s current in kA according to DIN VDE 0102
Tk Short-circuit time in s

Cable Cross-Section Current carrying capacity of copper short-circuiting cables for
Short-circuiting Earthing use in d.c. installations
cable cable kA
16 mm 2 16 mm 2 100
66.9 kA
25 mm 2 25 mm 2 I ‘‘ 50 49.6 kA
35 mm 2 35 mm 2 k 35.6 kA
30
50 mm 2 25 mm 2 24.8 kA
70 mm 2 35 mm 2 17.5 kA A = 95 mm
95 mm 2 35 mm 2 11.2 kA A = 70 mm 2
10 2
120 mm 2 50 mm 2 A = 50 mm 2
150 mm 2 50 mm 2 5 A = 35 mm 2
A = 25 mm
2
3 A = 16 mm
2
1
0.01 0.03 0.05 0.08 0.1 0.3 0.5 1 3 5 10 s
T
k
Initial cable temperature 20 °C Where:
Final cable temperature 250 °C A Cable cross-section in mm 2
Ik“ Maximum initial short-circuit alternating
A = 5.07 Ik“ √ Tk for Tk ≥ 0.08 s current in kA according to DIN VDE 0102
Tk Short-circuit time in s

Current carrying capacity of copper short-circuiting cables for
use on overhead contact lines of electric railways
kA
100
I ‘‘ 50
k
34.0 kA
30

10
4. EaS Devices
A = 50 mm
2
5
3

1
0.01 0.03 0.06 0.1 0.3 0.5 1 3 5 10 s
T
k
Where:
A Cable cross-section in mm 2
Ik“ Maximum initial short-circuit alternating
A = 6.0 Ik“ √ Tk for Tk ≥ 0.06 s current in kA according to DIN VDE 0102
Tk Short-circuit time in s
Valid as of January 1, 2019 You will find detailed product information on our website 55

S e D 4. a E 4. s EaS Devices i v e c a S E 4 . D e s c e v i