1. (Short Circuit Calculation) (Short Circuit) ** Co ordination **

2. (Short Circuit) (Short Circuit) ** Interrupting Rating ** 3. (Short Circuit) 4. Line to Ground Fault Line to Neutral Fault Line to Line Fault Double Line to Ground Fault Three Phase Fault !! Line to Ground Fault = 70 % Line to Line Fault = 15 % Double Line to Ground Fault = 10 % Three Phase Fault = 5 % 5. (Panel Board) MDB (Main Distribution Board) + - - - - () 6. - / - (> 1,000 A) (fuse & Circuit Breaker) 7. - - - - /- Fuse- Circuit Breaker 8. 1. 2. 3. 4. 9. (Symmetrical)(Unsymmetrical) IEC 60909 2 10. 1. ( MDB) IC 1. : (IU) (IM)MIUAIU IM IMB 11. (IU)IU = 100 * IFL,Tr IU IFL,Tr % Zk (Impedance Voltage) % Zk (IFL), 3 FL TrLI SV= S (VA)VL (V)(. = 400 V ; . = 416 V) 12. Impedance Voltage (Zk) Short Circuit Test Uk ZkXp Rp Xs RsW IIsh_s VVsh_sPsh_s Zk Z V meter/% ( ) s c 100kVrate 22 kV / 416-240 V Voltmeter 850 V. % 850 100k 22000 Z 3.86 % 13. Impedance Voltage (Zk) ItalyFrance 1 1600 kVA 24 kV/416-240 V, 3 FL TrLI SV=1600 1033 416==2,221 AMEA 24 kVCEI Std1600 kVA24 kV / 416-240 VIU 14. () , 100%FL TrUkIIZ= CEI Zk = 6.25 %2,221 100I =U 6.25 =35,536 A.