Selection Of The Power Cable Protection/Filter Input Protection Scheme - ABB PQFS Installation, Operation And Maintenance Instructions

Table 20: Allowed cable current for different cable sections noting the skin effect and typical
Cross section
[mm²] [AWG]
16 6
25 4
35 2
50 1-1/0
70 2/0
95 3/0
120 4/0
150 300MCM
185 350MCM
240 500MCM
300 600MCM
16 6
25 4
35 2
50 1-1/0
70 2/0
95 3/0
120 4/0
150 300MCM
185 350MCM
240 500MCM
300 600MCM
Remark: The highlighted values in
filter ratings. Note that in 4-wire systems, the neutral may have to carry up to 3 times
the line current rating of the filter.
6.7 Selection of the power cable protection/filter input protection
scheme
Once the power cables have been selected, a suitable cable and equipment protection
has to be selected. The protection only needs to protect the phases and not the neutral.
It is recommended to use fuses of type gG/gL with the RMS current ratings given in
Table 21.
42 Electrical design and installation  Manual Power Quality Filter PQFS
cable manufacturer data – Network frequency 60Hz
Nr of Derating
parallel due to
cables paralleling
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
2 0.8
Table 20
Copper
Rated Reduction Allowed
current factor current
[Arms] [Arms]
0.996
100
0.99
130
0.981
160
0.965
190
0.941
230
0.911
285
0.88
325
0.85
365
0.817
415
0.775
495
0.738
550
0.996
160
0.99
208
0.981
256
0.965
304
0.941
368
0.911
456
0.88
520
0.85
584
0.817
664
0.775
792
0.738
880
refer to cable sizes that correspond to typical
Aluminum
Rated Reduction
current factor
[Arms]
1
99 75
1
128 100
0.99
157 120
0.98
183 145
0.97
216 180
0.95
260 220
0.93
286 250
0.91
310 285
0.89
339 325
0.85
383 385
0.81
406 425
1
159 120
1
205 160
0.99
250 192
0.98
293 232
0.97
346 288
0.95
415 352
0.93
457 400
0.91
496 456
0.89
542 520
0.85
613 616
0.81
649 680
Allowed
current
[Arms]
75
100
119
143
175
210
233
260
288
326
346
120
160
190
228
280
336
374
416
460
522
553