URT
URT
6.3 Extraordinary Overloads Should occasional short time overloads without interruption by the fuse link be considered; or if at load currents of a certain value a short circuit breaker, and not a fuse link positioned behind the circuit breaker, should cause the interruption of the circuit, coefficient Cf3 has to be used. Similar to the application of coefficient B2, Cf3 also indicates the difference between the value of the current step and the smallest value of the time/current-curve obtained over the part periods t n .
I TCC >= I n / Cf3
F ig. 6.3 Extraordinary Overload
6.4 Application In sum, to find the appropriate rated current of the fuse link one first has to calculate the smallest possible rated current by
I rated >= I Load / (A1 * B1 * A2)
Then one needs to compare the single load current and the fuse curve
or/and I TCC of I rated >= I n / (Cf3) I TCC of I rated >= I n / (B2)
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