Transformer Fault Current Ranges
This calculation assumes an infinite bus, and the values provided are calculated at the secondary terminals of the transformer. For additional fault information, please contact systemplanning@coserv.com.
Note: CoServ reserves the right to make system modifications including feed changes and transformer upgrades to maintain service without customer notification. System modifications can result in higher fault currents.
|
Service
|
Phasing:
|
1
|
Voltage:
|
120/240
|
240/480
|
kVA Rating
|
Minimum Available
Fault (A)
|
Maximum Available
Fault ( A)
|
Minimum Available
Fault (A)
|
Maximum Available
Fault ( A)
|
10
|
1,042
|
2,778
|
521
|
1,389
|
15
|
1,563
|
4,167
|
781
|
2,083
|
25
|
2,604
|
6,944
|
1,302
|
3,472
|
37.5
|
3,906
|
10,417
|
1,953
|
5,208
|
50
|
5,208
|
13,889
|
2,604
|
6,944
|
75
|
7,813
|
20,833
|
3,906
|
10,417
|
100
|
10,417
|
27,778
|
5,208
|
13,889
|
167
|
17,181
|
34,792
|
8,591
|
17,396
|
250
|
16,855
|
52,083
|
8,428
|
26,042
|
|
Service
|
Phasing:
|
3
|
Voltage:
|
120/208
|
277/480
|
kVA Rating
|
Minimum Available
Fault (A)
|
Maximum Available
Fault ( A)
|
Minimum Available
Fault (A)
|
Maximum Available
Fault ( A)
|
75
|
3,621
|
7,710
|
1,569
|
3,341
|
112.5
|
5,431
|
10,073
|
2,353
|
4,365
|
150
|
7,241
|
13,431
|
3,138
|
5,820
|
225
|
10,862
|
20,146
|
4,707
|
8,730
|
300
|
14,482
|
26,862
|
6,276
|
11,640
|
500
|
24,137
|
31,905
|
10,459
|
13,825
|
750
|
33,868
|
39,131
|
14,597
|
16,957
|
1000
|
|
|
19,463
|
22,609
|
1500
|
|
|
29,194
|
33,914
|
2000
|
|
|
38,926
|
45,219
|
2500
|
|
|
48,657
|
56,523
|