Page 74 - Power Cables Catalogue.pdf

TECHNICAL INFORMATION

0.6 /1 KV CABLES
SHORT CIRCUIT CURRENTS (KA)

A. Permissible short circuit currents for copper conductors with xlpe insulation
AREA TRIPPING TIMES (SECONDS)
(Sq.mm) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 2 3 4 5
1.5 0.5 0.4 0.3 0.3 0.3 0.3 0.2 0.2 0.2 0.1 0.1 0.1 0.1
2.5 0.8 0.6 0.6 0.5 0.5 0.4 0.4 0.4 0.4 0.2 0.2 0.2 0.2
4 1.3 1.0 0.9 0.8 0.7 0.7 0.6 0.6 0.6 0.4 0.3 0.3 0.3
6 1.9 1.5 1.3 1.2 1.1 1.0 0.9 0.9 0.8 0.6 0.5 0.4 0.4
10 3.2 2.6 2.2 2.0 1.8 1.7 1.6 1.5 1.4 1.0 0.8 0.7 0.6
16 5.0 4.1 3.6 3.2 2.9 2.7 2.5 2.4 2.3 1.6 1.3 1.1 1.0
25 7.9 6.4 5.6 5.0 4.6 4.2 3.9 3.7 3.5 2.5 2.0 1.8 1.6
35 11.0 9.0 7.8 7.0 6.4 5.9 5.5 5.2 4.9 3.5 2.8 2.5 2.2
50 15.8 12.9 11.1 10.0 9.1 8.4 7.9 7.4 7.1 5.0 4.1 3.5 3.2
70 22.1 18.0 15.6 14.0 12.7 11.8 11.0 10.4 9.9 7.0 5.7 4.9 4.4
95 30.0 24.5 21.2 18.9 17.3 16.0 15.0 14.1 13.4 9.5 7.7 6.7 6.0
120 37.8 30.9 26.8 23.9 21.8 20.2 18.9 17.8 16.9 12.0 9.8 8.5 7.6
150 47.3 38.6 33.4 29.9 27.3 25.3 23.6 22.3 21.2 15.0 12.2 10.6 9.5
185 58.3 47.6 41.2 36.9 33.7 31.2 29.2 27.5 26.1 18.4 15.1 13.0 11.7

B. Permissible short circuit current for copper conductors with pvc insulation

AREA TRIPPING TIMES (SECONDS)
(Sq.mm) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 2 3 4 5
1.5 0.4 0.3 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.1
2.5 0.6 0.5 0.5 0.4 0.4 0.3 0.3 0.3 0.3 0.2 0.2 0.1 0.1
4 1.0 0.8 0.7 0.6 0.6 0.5 0.5 0.5 0.5 0.3 0.3 0.2 0.2
6 1.5 1.2 1.1 1.0 0.9 0.8 0.8 0.7 0.7 0.5 0.4 0.3 0.3
10 2.5 2.1 1.8 1.6 1.5 1.4 1.3 1.2 1.1 0.8 0.7 0.6 0.5
16 4.1 3.3 2.9 2.6 2.4 2.2 2.0 1.9 1.8 1.3 1.1 0.9 0.8
25 6.44 5.2 4.5 4.0 3.7 3.4 3.2 3.0 2.9 2.0 1.6 1.4 1.3
35 8.9 7.3 6.3 5.6 5.2 4.8 4.5 4.2 4.0 2.8 2.3 2.0 1.8
50 12.7 10.4 9.0 8.1 7.4 6.8 6.4 6.0 5.7 4.0 3.3 2.9 2.5
70 17.8 14.6 12.6 11.3 10.3 9.5 8.9 8.4 8.0 5.6 4.6 4.0 3.6
95 24.2 19.8 17.1 15.3 14.0 12.9 12.1 11.4 10.8 7.7 6.3 5.4 4.8
120 30.6 25.0 21.6 19.3 17.7 16.4 15.3 14.4 13.7 9.7 7.9 6.8 6.1
150 38.2 31.2 27.0 24.2 22.1 20.4 19.1 18.0 17.1 12.1 9.9 8.6 7.6
185 47.2 38.5 33.3 29.8 27.2 25.2 23.6 22.2 21.1 14.9 12.2 10.5 9.4

T2 + 234.5
Above values of currents are based on the formula: I = A 0.115 Log

t

where: I = Short circuit current (KA).
2
A = Conductor area (mm ).
T1 = Operating temperature (90ºC for XLPE, 70ºC for PVC).
T2 = Short circuit temperature (250C for XLPE, 160C for PVC).
t = Short circuit duration or tripping time.

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