GE AKD-10 Application Manual page 27

Table 26.1 Transformer forced cooled ratings
Self-cooled
Transformer type
Liquid filled: 65° C rise 750-2000
2500-5000
Liquid filled: 55/65° C rise 750-2000
2500-5000
Ventilated dry 750-2500
Cast coil 500-2500
3000-5000
Table 26.2 240 volts, three phase
Transformer
rating 3-phase Max short-circuit Full load
kVA and MVA available continuous
impedance from primary (amperes) Œ Ž current
percent system
50
100
150
300
250
4.5%
500
750
Unlimited
50
100
150
500
250
4.5%
500
750
Unlimited
50
100
150
Ž (2526)
750
250
5.75%
500
750
Unlimited
50
100
150
Ž (3368)
1000
250
5.75%
500
750
Unlimited
50
100
150
Ž (5052)
1500
250
5.75%
500
750
Unlimited
50
100
150
2000
250
5.75%
500
Ž (6735)
750
Unlimited
ΠWith transformer operating on base temperature rise, without fans. Larger frame
size main breaker may be required when dual temperature rise for forced cooled
transformers are used.
 Minimum impedance.
Ž Maximum forced cooled rating indicated in parentheses.
L = Long-time delay trip (overload tripping)
S = Short-time delay trip (selective fault tripping)
I = Instantaneous trip (high fault current fast tripping)
26
kVA % increase with fans
15%
25%
15% (fans) + 12% (65° C)
25% (fans) + 12% (65° C)
33%
40%
25%
Short-circuit rating sym current (A)
Transformer 100%
alone Motor load
14200
15000
15400
722 15600 2900
15800
15900
16000
21900
24100
24900
1203 25600 4800
26100
26300
26700
24900
27800
1804 28900
29800 7200
30600
30800
31400
31000
35600
2406 37500
39100 9600
40400
40900
41800
41200
49800
3608 53500
56800 14400
59600
60600
62800
49300
62100
67900
4811 73500 19200
78200
80000
83700
Main
Fully rated or
selective Selective
Fully rated
arrangement
LI
LS
Selectively
coordinated
arrangements
Distribution or motor control center
Long-time inst.
short-time Πor long-time Long-time
Combined short-time
17100
17900
18300
18500 WPS-08
18700
18800
18900
26700
28900
29700
30400 WPS-16
30900
31100
31500
32100
35000
36100
37000 WPS-20
37800
38000
38600
40600
45200
47100
48700 WPS-32
50000
50500
51400
55600
64200
67900
71200 WPS-40
74000
75000
77200
68500
81300
87100
92700 WPS-50
97400
99200
102900
Feeder circuit breakers
Zone
selective Fully rated
LS LSI LI
Long-time
short-time Long-time
inst. inst.
WPS-08 WPS-08 WPS-08
WPS-08
WPS-08 WPS-08
WPH-08
WPH-08 WPS-08 WPS-08
WPH-08 WPS-08 WPS-08
WPH-08 WPH-08
WPX-08
WPX-08 WPX-08
WPX-08 WPX-08 WPX-08
WPH-32 WPS-32 WPS-32
WPH-32 WPS-32 WPS-32
WPX-32 WPH-32 WPH-32
Fused
breaker
LI