Madel Pescription
Conditions of use
1、~40℃；Ambient temperature-40
2、Altitude not exceed 1000m
3、Wind speed not exceed 35m/s
4、Earthauake intensity: ≤ Ms8
5、Don't apply to following places
a、Burning or explosion hazardous
b、Serere shock or impact site
c、 different electro che mical gas effect and serious air pollutoinsolt fog area.
Fuse link Selection
Choose a fuse link which could melt immediately when the distribution transformer internal or the HV、LV wiring bushing occurs short-circuit. The following are the selection principles in practice. If the distribution transformer capacity below 60kVA, the fuse link should be 2~3 times the rated current of transformer. If the transformer capacity above 160kVa, the fuse link used is 1.5~2 times.You should also consider that if the fusing performance could perfectly match with the protection time of upstream devices. This is the key factor to judge if the fuse protection could be effect. The quick-break protection act time in distribution line is quite short, which lasts about 0.1s.According to the characteristic curve of fuse link, the current makes the fuse link melt should be no less than 20 times the rated current. This data is a necessary condition to ensure the fuse link could match with the circuit breaker. In actual operation, in power substation with above 50MVA short-circuit capacity, use 50-150mm2 aluminum wire as main line, within 1km from the substation and below 1250KVA transformer, or 2km far and below 800KVA transformer, or 10km far and 400KVA transformer, the short-circuit current in these transformers’ outlets could reach 20 times rated current of fuse link (choose fuse link 1.5 times rated current of transformer).For over-current protection in distribution lines, the act time is longer, which makes the coordination more easy. Thus the fuse link could be adopted for protection in most distribution transformers. Detailed specification can refer to table 1.
Ordering Instruction
1.Please indicate the product type, name, rated voltage, rated current, rated breaking current.
2.Environmental requirements(anti-pollution type,plateau type)
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