Current Rating And Voltage drop for cables & wires Upto and including 600/1000V.
Current ratings of cables given in tables below are based on the ERA(Electrical Research Association)
Report 69-30, Part V(for XLPE cables) and part III(For PVC cables) which is accepted world wide.
Single core copper, XLPE insulated armoured / unarmoured cables:
Nominal Area of Conductor |
In Air |
In Ground |
In Duct |
Voltage drop of 3 single core cables Trefoil |
Single core in Trefoil |
Single core in Trefoil |
Single core in Trefoil |
Unarmoured |
Armoured |
Armoured |
Armoured |
Sqmm |
A |
A |
A |
V/A/Km |
1.5 |
27 |
27 |
32 |
29 |
26.7 |
2.5 |
37 |
37 |
43 |
40 |
16.4 |
4 |
48 |
48 |
55 |
52 |
10.2 |
6 |
60 |
60 |
70 |
67 |
6.8 |
10 |
82 |
82 |
93 |
88 |
4.0 |
16 |
112 |
112 |
122 |
114 |
2.5 |
25 |
150 |
150 |
157 |
151 |
1.62 |
35 |
178 |
178 |
186 |
174 |
1.17 |
50 |
212 |
220 |
225 |
225 |
0.88 |
70 |
271 |
281 |
276 |
270 |
0.62 |
95 |
336 |
344 |
330 |
318 |
0.46 |
120 |
392 |
400 |
375 |
356 |
0.38 |
150 |
453 |
460 |
419 |
385 |
0.32 |
185 |
525 |
528 |
471 |
425 |
0.28 |
240 |
626 |
622 |
542 |
476 |
0.23 |
300 |
725 |
709 |
606 |
519 |
0.21 |
400 |
844 |
810 |
671 |
551 |
0.20 |
500 |
977 |
916 |
744 |
598 |
0.18 |
630 |
1129 |
1032 |
817 |
645 |
0.17 |
800 |
1282 |
1121 |
864 |
672 |
0.16 |
1000 |
1430 |
1216 |
915 |
714 |
0.15 |
Operating Conditions
Ambient Air temperature 30°C
Ground Temperature: 20°C
Depth of Laying: 0.5 m
Thermal Resitivity of soil: 1.2 K.m/W