Medium Voltage Power Cables Catalogue - AEC Online

Table E.12
Derating factors for groups of three-phase circuits of single-core cables in single-way ducts
Number of cables
in group
Spacing between group centers
Touching 200 mm 400 mm 600 mm 800 mm
2
3
4
5
6
7
8
9
10
11
12
0.78
0.66
0.59
0.55
0.51
0.48
0.46
0.44
0.43
0.42
0.40
0.85
0.75
0.70
0.66
0.64
0.61
0.60
0.58
0.57
0.56
0.55
0.89
0.81
0.77
0.74
0.72
0.71
0.70
0.69
0.68
0.67
0.67
0.91
0.85
0.82
0.80
0.78
0.77
0.76
0.76
-
-
-
0.93
0.88
0.86
0.84
0.83
0.82
-
-
-
-
-
Table E.13
Derating factors for groups of more than one three-core cable in air
Cables on horizontal perforated trays (touching)
Clearance from the wall ≥ 20 mm
Number of trays
Number of cables (three-phase circuits)
1 2 3 4 6 9
Laying form
1
1.00
0.88
0.82
0.79
0.76
0.73
2
1.00
0.87
0.80
0.77
0.73
0.68
3
1.00
0.86
0.79
0.76
0.71
0.66
20 mm
Cables on horizontal perforated trays (spaced)
Clearance = cable diameter (D e )
Clearance from the wall ≥ 20 mm
Number of trays
Number of cables (three-phase circuits)
1 2 3 4 6 9
Laying form
1
1.00
1.00
0.98
0.95
0.91
-
D e
2
1.00
0.99
0.96
0.92
0.87
-
3
1.00
0.98
0.95
0.91
0.85
-
20 mm