KYORITSU 4116A - Page 16

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ForinstanceinaTNsystemwithnominalmainsvoltageUo=230V
protectedbygGfusesthe
Ia
andmax
Zs
valuescouldbe:
Usingthecurrentrangesonmodels4120Aand4118Acanbe alsotested
theProspectiveFaultcurrent.
ProspectiveFaultcurrentmeasuredbyinstrumentsmustbehigherthan
Ia
oftheprotectivedeviceconcerned
PracticalexampleofverificationoftheprotectioninaTNsystemaccording
totheinternationalStandardIEC60364.
Fig.9
Rating
(A)
Disconnectingtime5s
Ia(A) Zs(Ω) Ia(A) Zs(Ω)
Disconnectingtime0.4s
6
10
16
20
25
32
40
50
63
80
100
28
46
65
85
110
150
190
250
320
425
580
8.2
5
3.6
2.7
2.1
1.53
1.21
0.92
0.71
0.54
0.39
47
82
110
147
183
275
320
470
550
840
1020
4.9
2.8
2.1
1.56
1.25
0.83
0.72
0.49
0.42
0.27
0.22
L1
L2
L3
N
PE
R
O
Fuse
g
G 16A