Note:
▲When the protective device is a residual current device(RCD), Ia is the rated
residual operating current IΔn.
For instance in a TN system with a nominal mains voltage of Uo = 230V
protected by type gG fuses the Ia and maximum Zs values could be:
Rating Disconnecting Time 5s Disconnecting Time 0.4s
(A) Ia (A) Zs (Ω) Ia (A) Zs (Ω)
6 28 8.20 47 4.90
10 46 5.00 82 2.80
16 65 3.60 110 2.10
20 85 2.70 147 1.56
25 110 2.10 183 1.25
32 150 1.53 275 0.83
40 190 1.21 320 0.72
50 250 0.92 470 0.49
63 320 0.71 550 0.42
80 425 0.54 840 0.27
100 580 0.39 1020 0.22
If the prospective fault current is measured, its value must be higher than the
Ia value of the protective device concerned.
Fig. 22
LOOP/PSC/PFC
To Next Page
Loading...
Need help?
General
