HomeMy WebLinkAboutFault_current_calculator_2014 (1) (version 1) (2) by:John Sokolik Ver. 2014
Utility Fault Current amperes kVA = 50
E = 240
I = kVA x 1000 = trans. FLA trans. FLA = 208
Isca = trans. FLA x 100 x PF PF = 100%
transformer Z Z = 5.80%
Isca = ampere short-circuit current RMS symmetrical. Isca = 3,592 amperes
Point to Point Method
Length (distance) L = 120
2 x L x I (ASC) Isca = 3,592
N x C x E L-N # conductors per phase N = 1
C = 16,813 E L - L =240 Volt
f = 0.214
C = 16,813
Multiplier E L - N =120 Volt
f = 0.641
M = 1
1 + f Line to Line M = 0.824
Line to Neutral M = 0.609
Isca x M = fault current at terminals of main disconnect L- L =2,960 amperes
Isca x M = fault current at terminals of main disconnect L- N =3,283 amperes
Fault Current from
L = 40
2 x L x I (ASC) Isca = 2,960 Phase 3,283 Neutral
N x C x E L-N # conductors per phase N = 1
C = 16,813 Phase Conductor
Volt Line to Line E L - L =240 Volt
f = 0.059
C = 16,813 Neutral Conductor
Volt Line to Neutral E L - N =120 Volt
Multiplier f = 0.130
M = 1 Line to Line M = 0.945
1 + f Line to Neutral M = 0.885
2,796 amperes
2,905 amperes
Branch Circuit Fault from
L = 115
2 x L x I (ASC) Isca = 2,796 Phase 2,905 Neutral
N x C x E L-N # conductors per phase N = 1
C = 0 Phase Conductor
Volt Line to Line E L - L =240 Volt
f = 0.000
C = 0 Neutral Conductor
Volt Line to Neutral E L - N =120 Volt
Multiplier f = 0.000
M = 1 Line to Line M = 1.000
1 + f Line to Neutral M = 1.000
2,796 amperes
2,905 amperes
Isca x M = fault current at terminal of the panel L- L =
Isca x M = fault current at terminal of the panel L- N =
TRANFORMER TO MAIN Panel __
Single Phase Feeder
'f ' factor =
Phase conductor constant
Length (distance)
Neutral conductor constant
Calculation does not include motor contribution
Fault Current at Service Equipment
Volt Line to Line
Neutral conductor constant Neutral Conductor
Volt Line to Neutral
'f ' factor =
Phase conductor constant Phase Conductor
Calculation does not include motor contribution
(example) FROM PANEL TO OUTLET
Single Phase Branch
'f ' factor =
Phase conductor constant
Length (distance)
Isca x M = fault current at terminal of the panel L- N =
Neutral conductor constant
Isca x M = fault current at terminal of the panel L- L =
6 UNIT APT 258 S 3rd WEST
CORCORAN 6 UNIT
Available Fault Current Calculation
E
jmp1jds@comcast.net
=