Catálogo fusibles SIBA 2022

URT

URT

Checking the time-current-curve of the rating 355A at 1020s: 560A

560 A >= 260A / 0.6 = 433A

Checking the time-current-curve of the rating 355A at 300s: 650A

650A >= 340A / 0.6 = 567A

Based on the above calculation, a fuse rating of 355A will carry the load represented in the diagram continuously. As a next step, one should observe the          of the semiconductor and compare them with the fuse integral. In this case it may be necessary to reduce the fuse rated current. Extraordinary Overloads An impulse load on the D.C. side of a converter causes a current through the fuse link as shown in the load diagram. A load-break-switch interrupts such a load in a period of <200ms. One should determine whether the fuse link can carry the current for the duration of the overload without interruption.

I 1 max = 2000A

t 1 = 14ms

( I 1 RMS about 1300 A ) I 2 RMS = 900A SQB Fuse Link Size 1 Rated current 355A Cf3 = 0.8

t 2 = 200ms

Review of the load first wave and the load-RMS value, and comparison with the time-current-curve(TCC) of the rating of 355A: I TCC >= I n / Cf3

Checking the time-current-curve of the rating 355A at 14ms: 1900A

1900A >= 1300A / 0.8 = 1625 A

Checking the time-current-curve of the rating 355A at 200ms: 1600A

1600A >= 900A / 0.8 = 1125 A Based on the above calculation, a fuse rating of 355 A will carry the load according to the diagram continuously.

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