The current ratings given are based on normal condition of installation described below:
Cables shall only be operated at their full rating if the minimum current at which circuit protection is designed to operate does not exceed 1.5 times (in the case of cables in air or in ducts) or 1.3 times (in the case of cables laid direct in the ground).
| Area of Conductor | Aluminum Conductor | Copper Conductor | |||
| Sq. mm | GPPVC | HRPVC | GPPVC | HRPVC | |
| 1.5 | 0.1126 | 0.097 | 0.169 | 0.153 | |
| 2.5 | 0.1878 | 0.162 | 0.283 | 0.255 | |
| 4 | 0.3004 | 0.259 | 0.452 | 0.406 | |
| 6 | 0.4507 | 0.389 | 0.67 | 0.612 | |
| 10 | 0.7512 | 0.648 | 1.132 | 1.020 | |
| 16 | 1.200 | 1.087 | 1.810 | 1.632 | |
| 25 | 1.870 | 1.620 | 2.830 | 2.550 | |
| 35 | 2.620 | 2.270 | 3.960 | 3.570 | |
| 50 | 3.750 | 3.243 | 5.660 | 5.100 | |
| 70 | 5.250 | 4.540 | 7.920 | 7.140 | |
| 95 | 7.13 | 6.150 | 10.750 | 9.690 | |
| 120 | 9.00 | 7.784 | 13.580 | 13.340 | |
| 150 | 11.260 | 9.730 | 16.980 | 15.300 | |
| 185 | 13.890 | 12.000 | 20.940 | 18.870 | |
| 240 | 18.020 | 15.560 | 17.160 | 24.480 | |
| 300 | 22.530 | 19.460 | 33.960 | 30.600 | |
| 400 | 30.040 | 25.940 | 45.280 | 40.800 | |
| 500 | 37.560 | 32.43 | 56.600 | 51.000 | |
| 630 | 47.320 | 40.860 | 71.310 | 64.250 | |
Note : For cables in air, no reduction in current rating is necessary provided that
> The horizontal clearance between circuits is:
(a) not less than six times the overall diameter of an individual cable, and
(b) not less than the overall width of an individual circuit, except that the horizontal clearance need not in any case exceed 150 mm
> The vertical clearance between circuits is not less than 150mm
> If the number of circuits exceeds, they are installed in a horizontal plane.
However for installations conditions other than above current rating factors incorporated in IS 3961 Part-Il may please be applied.
| HP | KW | Single Phase Amp | Three Phase Amp | Recommended Cable Size Sq mm. | ||
| 0.5 | 0.37 | 3.7 | 1.0 | 1.5 | Copper | |
| 0.75 | 0.55 | 5.0 | 1.3 | 1.5 | Copper | |
| 1.0 | 0.75 | 6.5 | 1.9 | 1.5 | Copper | |
| 1.5 | 1.10 | 11.5 | 2.6 | 1.5 | Copper | |
| 2.0 | 1.50 | --- | 3.7 | 1.5 | Copper | |
| 3.0 | 2.20 | --- | 4.8 | 1.5 | Copper | |
| 5.0 | 3.70 | --- | 7.8 | 1.5 | Copper | |
| 7.5 | 5.50 | --- | 11.2 | 1.5 | Copper | |
| 10.0 | 7.50 | --- | 15.5 | 2.5 | Copper | |
| 12.5 | 9.30 | --- | 19.0 | 2.5 | Copper | |
| 15.0 | 11.00 | --- | 22.0 | 6 | Aluminium | |
| 20.0 | 15.00 | --- | 29.0 | 10 | Aluminium | |
| 25.0 | 18.50 | --- | 35.0 | 16 | Aluminium | |
| 30.0 | 22.00 | --- | 40.0 | 16 | Aluminium | |
| 35.0 | 26.00 | --- | 47.0 | 25 | Aluminium | |
| 40.0 | 30.00 | --- | 53.0 | 25 | Aluminium | |
| 50.0 | 37.00 | --- | 65.0 | 35 | Aluminium | |
| 60.0 | 45.00 | --- | 80.0 | 50 | Aluminium | |
| 75.0 | 55.00 | --- | 94.0 | 70 | Aluminium | |
| 100.0 | 75.00 | --- | 127.0 | 95 | Aluminium | |
| 125.0 | 90.00 | --- | 152.0 | 150 | Aluminium | |
1 The system of power & voltage source where the cable are being used.
2 Conditions of installation at site.
3 Current carrying capacity of cable.
4 Voltage drop of the cable.
5 Short circuit capacity of cable.
6 Availability of the selected size of cable.
Formula for calculating the Short Circuit for other durations
It = 
Where......
I1 = Short Circuit Current for one second.
It = Short Circuit fort t seconds.
t = Duration in second.
Maximum Conductor temperature during short circuit is 160° C for PVC and HR PVC Cables.
The Following Minimum bending radius should be observed for Ashocab CABLE in order that the cables, specially insulation, may not get damage in installation.
Single Core Ashocab Cable --15 X D
Multi Core Ashocab Cable --15 X D
Where D is the overall diameter of cable.
(a) When conductor pulled by pulling eye:
(i) Aluminium Conductor Cable (Newton) -- 30 X Total conductor area in sq.mm.
(ii) Cupper Conductor Cable (Newton) -- 50 X Total conductor area in sq.mm.
(b) When cable pulled with stocking :
(i) Unarmoured cable 1.1K. V. (Newton) -- 5 X D2
(ii) Armoured cable 1.1K. V. (Newton) -- 9 X D2
Where D is the overall diameter of cable.
