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3
Selection and application
3-8 Selecting an MCCB for capacitor circuit
Table 3-20 (2) MCCB rated current application examples for three-phase capacitor equipment capacity
Rated frequency
(Hz)
Rated voltage
(V)
Rated equipment
capacity (kvar)
Rated current
(A)
Capacitor rating
Series reactor 6%
MCCB rated
current (A)
MC type
(reference)
(kvar)
(μF)
(kvar)
(mH)
50
200
1.34
3.9
1.43
100
0.09
6.06
10
SC–03
2.67
7.7
2.84
200
0.17
3.04
15
SC–03
3.34
9.6
3.55
250
0.21
2.43
15
SC–03
4.01
11.6
4.27
300
0.26
2.03
20
SC–03
5
14.4
5.32
374
0.32
1.63
30
SC–4–0
10
28.9
10.64
748
0.64
0.81
50
SC–N1
15
43.3
15.96
1,122
0.96
0.54
75
SC-N2S
20
57.7
21.28
1,496
1.28
0.41
100
SC–N3
25
72.2
26.60
1,870
1.60
0.33
125
SC-N4
30
86.6
31.91
2,244
1.91
0.27
150
SC–N4
40
115.5
42.55
2,992
2.55
0.20
175
SC–N7
50
144.3
53.19
3,740
3.19
0.16
225
SC–N8
、
N10
75
216.5
79.79
5,610
4.79
0.11
350
SC–N11
100
288.7
106.38
7,480
6.38
0.08
500
SC–N12
150
433.0
159.57
11,220
9.57
0.05
700
SC–N14
200
577.4
212.77
14,961
12.77
0.04
900
300
866.0
319.15
22,441
19.15
0.03
1400
400
1.07
1.5
1.14
20
0.07
30.38
5
SC–03
1.60
2.3
1.70
30
0.10
20.32
5
SC–03
2.67
3.9
2.84
50
0.17
12.18
10
SC–03
4.01
5.8
4.27
75
0.26
8.11
10
SC–03
5
7.2
5.32
94
0.32
6.50
15
SC–03
10
14.4
10.64
187
0.64
3.25
30
SC–4–0
15
21.7
15.96
281
0.96
2.17
40
SC-N1
20
28.9
21.28
374
1.28
1.63
50
SC–N1
25
36.1
26.60
468
1.60
1.30
60
SC-N2
30
43.3
31.91
561
1.91
1.08
75
SC–N2S
40
57.7
42.55
748
2.55
0.81
100
SC–N3
50
72.2
53.19
935
3.19
0.65
125
SC–N4
75
108.3
79.79
1,403
4.79
0.43
175
SC–N7
100
144.3
106.38
1,870
6.38
0.33
225
SC–N8
、
N10
150
216.5
159.57
2,805
9.57
0.22
350
SC–N11
200
288.7
212.77
3,740
12.77
0.16
500
SC–N12
300
433.0
319.15
5,610
19.15
0.11
700
SC–N14
60
220
0.97
2.5
1.03
50
0.06
12.17
5
SC–03
1.94
5.1
2.06
100
0.12
6.08
10
SC–03
2.91
7.6
3.10
150
0.19
4.06
15
SC–03
3.88
10.2
4.13
200
0.25
3.04
20
SC–03
5
13.1
5.32
258
0.32
2.36
20
SC–03
10
26.2
10.64
515
0.64
1.18
40
SC–N1
15
39.4
15.96
773
0.96
0.79
60
SC-N2
20
52.5
21.28
1,030
1.28
0.59
100
SC–N2S
25
65.6
26.60
1,288
1.60
0.47
100
SC-N3
30
78.7
31.91
1,546
1.91
0.39
125
SC–N4
40
105.0
42.55
2,061
2.55
0.30
175
SC–N7
50
131.2
53.19
2,576
3.19
0.24
200
SC–N7
75
196.8
79.79
3,864
4.79
0.16
300
SC–N11
100
262.4
106.38
5,152
6.38
0.12
400
SC–N12
150
393.6
159.57
7,728
9.57
0.08
600
SC–N14
200
524.9
212.77
10,303
12.77
0.06
800
SC–N16
300
787.3
319.15
15,455
19.15
0.04
1200
440
1.55
2.0
1.65
20
0.10
30.45
5
SC–03
2.33
3.1
2.48
30
0.15
20.26
5
SC–03
3.11
4.1
3.31
40
0.20
15.18
10
SC–03
3.88
5.1
4.13
50
0.25
12.17
10
SC–03
5
6.6
5.32
64
0.32
9.44
10
SC–03
10
13.1
10.64
129
0.64
4.72
20
SC–03
15
19.7
15.96
193
0.96
3.15
30
SC-4-1
20
26.2
21.28
258
1.28
2.36
40
SC–N1
25
32.8
26.60
322
1.60
1.89
50
SC-N1
30
39.4
31.91
386
1.91
1.57
60
SC–N2
40
52.5
42.55
515
2.55
1.18
100
SC–N2S
50
65.6
53.19
644
3.19
0.94
100
SC–N3
75
98.4
79.79
966
4.79
0.63
150
SC–N5, N5A
100
131.2
106.38
1,288
6.38
0.47
200
SC–N7
150
196.8
159.57
1,932
9.57
0.31
300
SC–N11
200
262.4
212.77
2,576
12.77
0.24
400
SC–N12
300
393.6
319.15
3,864
19.15
0.16
600
SC–N14
Notes: • The MCCB rated current should be approx. 150% of the capacitor rated current.
• The MCCB should have enough breaking capacity to cut off short-circuit current in the circuit.
• Use a magnetic contactor to switch multiple capacitor banks for automatic power factor regulation. Be sure to install series-connected reactors as well.
Add up the total capacitance here to select the rated current for the main MCCB.
• As a rule, use series-connected reactors totaling 6% of the impedance.