Calculation of
stready state short-circuit current in low voltage line according to IEC 60909-0
This sheet allows the online calculation of three-phase short-circuit current
Icc low voltage three-phase , double-phase and Icc single-phase between phase
and neutral or protection conductor at the and of the line, known the supply
voltage, the short circuit to start line Icc0 , and power factor cosfi0,the type
of low-voltage cable used, the current carrying capacity Iz and the conductor
material used (copper (cu) or aluminum (al)) and the length of the line,
according to IEC 60909-0.
Intermediate results of calculations: let-trough energy cable , loop
resistance, reactance, and impedance of the line.
N.b.: use the decimal point for numbers, do not use the comma!.
Phase-to-phase voltage(volt):
Short-circuit current at start line ICC0 (KA):
CofiICC0:
PHASE: cable C.section(mmq):
numer of cables:
conductor type:
NEUTRAL/PROTECTION:cross-section(mmq):
numer of cables::
Line length (m.):
RESULTS OF CALCULATION OF THE IMPEDANCE OF THE CABLE LOOP FAULT AND MINIMUM OR
MAXIMUM SHORT-CIRCUIT CURRENT, LOW VOLTAGE
Let-Through Energy of the cable line = 0
Line impedance Zl (mOhm) =
Line
resistance Rl(mOhm) =
Line
reactance Xl(mOhm) =
( Minimum or max.) three-phase short-circuit
at end line ICC 3F (KA) =
( Minimum or max. )phase-phase short-circuit at end line ICC
F-F (KA) =
(Minimum or max ) phase-protection/neutral short-circuit at end line ICCF-N/PE
(KA) = 2144
When Icc is calculate with C=1,05 instead of C=0,95 and the short circuit final
temperature assumes =20 °C instead of 160°C-250°C, results change and ( minimum
)Icc became ( maximum ) Icc at end line .
________________________________________________________________________________________________________
1
NUMERO CONDUTTORI
1
2
3
4
POSA ARIA IMPEDITA- UNIPOLARI-PVC
13.5
13.5
12
10.5
POSA ARIA IMPEDITA- MULTIPOLARI-EPR
17
17
15
13.5
POSA ARIA LIBERA- MULTIPOLARI-PVC
15
15
13.5
12
POSA ARIA LIBERA- MULTIPOLARI-EPR
19
19
17
15
POSA ARIA LIBERA- UNIPOLARI CON GUAINA-PVC
17
17
15
13.5
POSA ARIA LIBERA- UNIPOLARI CON GUAINA-EPR
23
21
19
17
1
1
NUMERO CAVI MULTIPOLARI O CIRCUITI ADIACENTI
1
2
3
4
5
6
7
8
9
12
16
20
UNICO TUBO
1
0.8
0.7
0.65
0.6
0.57
0.54
0.52
0.5
0.45
0.41
0.38
TUBI ACCOSTATI A PARETE- 1 STRATO
1
0.94
0.91
0.88
0.87
0.86
0.86
0.86
0.86
0.86
0.86
0.86
TUBI ACCOSTATI A PARETE- 2 STRATI
0.92
0.86
0.84
0.81
0.80
0.79
0.79
0.79
0.79
0.79
0.79
0.79
TUBI ACCOSTATI A PARETE- 3 STRATI
0.85
0.80
0.77
0.75
0.74
0.73
0.73
0.73
0.73
0.73
0.73
0.73
TUBI ACCOSTATI SOTTO INTONACO- 1 STRATO
1
0.87
0.77
0.72
0.68
0.65
0.65
0.65
0.65
0.65
0.65
0.65
TUBI ACCOSTATI SOTTO INTONACO- 2 STRATI
0.87
0.76
0.67
0.63
0.59
0.57
0.57
0.57
0.57
0.57
0.57
0.57
TUBI ACCOSTATI SOTTO INTONACO- 3 STRATI
0.77
0.67
0.59
0.55
0.52
0.50
0.50
0.50
0.50
0.50
0.50
0.50
SINGOLO STRATO SU PAVIMENTO, PASSERELLA NON FORATA,PARETE