For normal operation of the steam generator it is important to select a power cable of the required cross-section. Below are tables taken from the regulatory document “Rules for the Installation of Electrical Installations” of the 2009 edition. Using this reference data, you can be sure that the power cable is selected correctly.
Electrical Installation Rules
Permissible continuous current for wires with rubber and polyvinyl chloride insulation with aluminum cores
| Cross-section of the conductive core, mm2 | Current, A, for wires laid | |||||
| openly | in one pipe | |||||
| two single-core | three single-core | four single-core | one two-core | one three-wire | ||
| 2 | 21 | 19 | 18 | 15 | 17 | 14 |
| 2,5 | 24 | 20 | 19 | 19 | 19 | 16 |
| 3 | 27 | 24 | 22 | 21 | 22 | 18 |
| 4 | 32 | 28 | 28 | 23 | 25 | 21 |
| 5 | 36 | 32 | 30 | 27 | 28 | 24 |
| 6 | 39 | 36 | 32 | 30 | 31 | 26 |
| 8 | 46 | 43 | 40 | 37 | 38 | 32 |
| 10 | 60 | 50 | 47 | 39 | 42 | 38 |
| 16 | 75 | 60 | 60 | 55 | 60 | 55 |
| 25 | 105 | 85 | 80 | 70 | 75 | 65 |
| 35 | 130 | 100 | 95 | 85 | 95 | 75 |
| 50 | 165 | 140 | 130 | 120 | 125 | 105 |
| 70 | 210 | 175 | 165 | 140 | 150 | 135 |
| 95 | 255 | 215 | 200 | 175 | 190 | 165 |
| 120 | 295 | 245 | 220 | 200 | 230 | 190 |
| 150 | 340 | 275 | 255 | – | – | – |
| 185 | 390 | – | – | – | – | – |
| 240 | 465 | – | – | – | – | – |
| 300 | 535 | – | – | – | – | – |
| 400 | 645 | – | – | – | – | – |
Permissible continuous current for cables with aluminum conductors with rubber or plastic insulation in lead, polyvinyl chloride and rubber sheaths.
| Cross-section of the conductive core, mm2 |
Current, A, for cables |
||||
|
single-core |
two-wire |
three-core |
|||
|
when laying |
|||||
|
in the air |
in the air |
in the ground |
in the air |
in the ground |
|
|
2,5 |
23 |
21 |
34 |
19 |
29 |
|
4 |
31 |
29 |
42 |
27 |
38 |
|
6 |
38 |
38 |
55 |
32 |
46 |
|
10 |
60 |
55 |
80 |
42 |
70 |
|
16 |
75 |
70 |
105 |
60 |
90 |
|
25 |
105 |
90 |
135 |
75 |
115 |
|
35 |
130 |
105 |
160 |
90 |
140 |
|
50 |
165 |
135 |
205 |
110 |
175 |
|
70 |
210 |
165 |
245 |
140 |
210 |
|
95 |
250 |
200 |
295 |
170 |
255 |
|
120 |
295 |
230 |
340 |
200 |
295 |
|
150 |
340 |
270 |
390 |
235 |
335 |
|
185 |
390 |
310 |
440 |
270 |
385 |
|
240 |
465 |
– |
– |
– |
– |
|
Note. Permissible continuous currents for four-core cables with plastic insulation for voltages up to 1 kV can be selected according to Table 1.3.7, as for three-core cables, but with a coefficient of 0.92. |
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Permissible continuous current for wires and cords with rubber and PVC insulation with copper conductors.
| Cross-section of the conductive core, mm2 | Current, A, for wires laid | |||||
| openly | in one pipe | |||||
| two single-core | three single-core | four single-core | one two-wire | one three-wire | ||
| 0,5 | 11 | – | – | – | – | – |
| 0,75 | 15 | – | – | – | – | – |
| 1 | 17 | 16 | 15 | 14 | 15 | 14 |
| 1,2 | 20 | 18 | 16 | 15 | 16 | 14,5 |
| 1,5 | 23 | 19 | 17 | 16 | 18 | 15 |
| 2 | 26 | 24 | 22 | 20 | 23 | 19 |
| 2,5 | 30 | 27 | 25 | 25 | 25 | 21 |
| 3 | 34 | 32 | 28 | 26 | 28 | 24 |
| 4 | 41 | 38 | 35 | 30 | 32 | 27 |
| 5 | 46 | 42 | 39 | 34 | 37 | 31 |
| 6 | 50 | 46 | 42 | 40 | 40 | 34 |
| 8 | 62 | 54 | 51 | 46 | 48 | 43 |
| 10 | 80 | 70 | 60 | 50 | 55 | 50 |
| 16 | 100 | 85 | 80 | 75 | 80 | 70 |
| 25 | 140 | 115 | 100 | 90 | 100 | 85 |
| 35 | 170 | 135 | 125 | 115 | 125 | 100 |
| 50 | 215 | 185 | 170 | 150 | 160 | 135 |
| 70 | 270 | 225 | 210 | 185 | 195 | 175 |
| 95 | 330 | 275 | 255 | 225 | 245 | 215 |
| 120 | 385 | 315 | 290 | 260 | 295 | 250 |
| 150 | 440 | 360 | 330 | – | – | – |
| 185 | 510 | – | – | – | – | – |
| 240 | 605 | – | – | – | – | – |
| 300 | 695 | – | – | – | – | – |
| 400 | 830 | – | – | – | – | – |
Permissible continuous current for wires with copper conductors with rubber insulation in metal protective sheaths and cables with copper conductors with rubber insulation in a lead, polyvinyl chloride, nyrite or rubber sheath.
|
Cross-section of the conductive core, mm2 |
Current*, A, for wires and cables |
||||
|
single-core |
two-wire |
three-core |
|||
|
when laying |
|||||
|
in the air |
in the air |
in the ground |
in the air |
in the ground |
|
|
1 |
2 |
3 |
4 |
5 |
6 |
|
1,5 |
23 |
19 |
33 |
19 |
27 |
|
2,5 |
30 |
27 |
44 |
25 |
38 |
|
4 |
41 |
38 |
55 |
35 |
49 |
|
6 |
50 |
50 |
70 |
42 |
60 |
|
10 |
80 |
70 |
105 |
55 |
90 |
|
16 |
100 |
90 |
135 |
75 |
115 |
|
25 |
140 |
115 |
175 |
95 |
150 |
|
35 |
170 |
140 |
210 |
120 |
180 |
|
50 |
215 |
175 |
265 |
145 |
225 |
|
70 |
270 |
215 |
320 |
180 |
275 |
|
95 |
325 |
260 |
385 |
220 |
330 |
|
120 |
385 |
300 |
445 |
260 |
385 |
|
150 |
440 |
350 |
505 |
305 |
435 |
|
185 |
510 |
405 |
570 |
350 |
500 |
|
240 |
605 |
– |
– |
– |
– |
|
* Currents apply to wires and cables both with and without a neutral conductor. |
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