Current carrying capacity of medium voltage cables

acc. to HD 620 S2, part 10C

Bayka products
The values given below are applicable to these products:

Column copper conductor
N2XSY / N2XS2Y / N2XS(F)2Y / N2XS(FL)2Y:

Metro MV

Column aluminium conductor
NA2XSY / NA2XS2Y / N2XS(F)2Y / NA2XS(FL)2Y:

Metro MV AL

Basic conditions

temperatures °C (conductor)
highest permissible operating temperature +90
highest short circuit temperature +250

Concentric conductors are grounded on both ends.
Operating frequency 50 Hz.
The tabulated loading capacities ​​are based on various conditions such as
– operating mode,
– laying conditions,
– environmental conditions.
In the event of deviating operating conditions, the loading capacities ​​are to be multiplied by suitable conversion factors, which are based on the same calculation principles and operating conditions as the given values.

Current carrying capacity of medium voltage cables

Laying in earth (20°C)

recommended values acc. to HD 620 S2, part 10C, table 7

copper conductor
N2XSY / N2XS2Y / N2XS(F)2Y / N2XS(FL)2Y
 aluminium conductor
NA2XSY / NA2XS2Y / N2XS(F)2Y / NA2XS(FL)2Y
Uo / U
 6 / 10 kV
 12 / 20 kV
 18 / 30 kV
 6 / 10 kV
 12 / 20 kV
 18 / 30 kV
cross-section
mm²		 copper conductor
rated current in A		 aluminium conductor
rated current in A
25 157 179 – – – – – – – – – –
35 187 212 189 213 – – – – – – – –
50 220 249 222 250 225 251 171 194 172 195 174 195
70 268 302 271 303 274 304 208 236 210 237 213 238
95 320 359 323 360 327 362 248 281 251 282 254 283
120 363 405 367 407 371 409 283 318 285 319 289 321
150 405 442 409 445 414 449 315 350 319 352 322 354
185 456 493 461 498 466 502 357 394 361 396 364 399
240 526 563 532 568 539 574 413 452 417 455 422 458
300 591 626 599 633 606 640 466 506 471 510 476 514
400 662 675 671 685 680 695 529 558 535 564 541 570
500 744 748 754 760 765 773 602 627 609 634 616 642
630 – – – – – – – – – – – –
800 – – – – – – – – – – – –
1000 – – – – – – – – – – – –

Current carrying capacity of medium voltage cables

Laying in air (30°C)

recommended values acc. to HD 620 S2, part 10C, table 8

copper conductor
N2XSY / N2XS2Y / N2XS(F)2Y / N2XS(FL)2Y
 aluminium conductor
NA2XSY / NA2XS2Y / N2XS(F)2Y / NA2XS(FL)2Y
Uo / U
 6 / 10 kV
 12 / 20 kV
 18 / 30 kV
 6 / 10 kV
 12 / 20 kV
 18 / 30 kV
cross-section
mm²		 copper conductor
rated current in A		 aluminium conductor
rated current in A
25 163 194 – – – – – – – – – –
35 197 235 200 235 – – – – – – – –
50 236 282 239 282 241 282 183 219 185 219 187 219
70 294 350 297 351 299 350 228 273 231 273 232 273
95 358 426 361 426 363 425 278 333 280 332 282 331
120 413 491 416 491 418 488 321 384 323 384 325 382
150 468 549 470 549 472 548 364 432 366 432 367 429
185 535 625 538 625 539 624 418 496 420 494 421 492
240 631 731 634 731 635 728 494 583 496 581 496 578
300 722 831 724 830 725 828 568 666 569 663 568 659
400 827 920 829 923 831 922 660 755 660 753 650 750
500 949 1043 953 1045 953 1045 767 868 766 866 764 861
630 – – – – – – – – – – – –
800 – – – – – – – – – – – –
1000 – – – – – – – – – – – –

Current carrying capacity of medium voltage cables

Permissible short-circuit temperatures and rated short-time current densities

Recommended values acc. to HD 620 S2, part 10C, table 12

Cables with admissible short-circuit temperature
°C		 rated short-circuit current densities in A/mm²
for a rated short-circuit duration of 1s
conductor temperature at the beginning of short-circuit in °C
90 80 70 60 50 40 30 20
copper conductor 250 143 149 154 159 165 170 176 181
aluminium conductor 250 94 98 102 105 109 113 116 120


Download PDF (technical Data / plastic insulated medium voltage cables)