This part of IEC 60077 aims to provide additional or revised rules for high voltage fuses, serving as a supplement to those outlined in IEC 60077-2.
It is important to note that the term “high voltage fuses” used in this product standard pertains to the voltages utilized in the field of railway rolling stock.
The focus here is on fuses intended for connection into power and/or auxiliary circuits. These circuits are rated between 600 V d.c. and 3000 V d.c., according to IEC 60850. The fuses can also be utilized in auxiliary a.c. circuits up to a nominal voltage of 1500 V.
It is possible to modify some of these rules after agreement between the user and manufacturer, allowing them to be applied to fuses installed on vehicles other than rail rolling stock, such as mine locomotives, trolleybuses, etc.
This product standard, along with IEC 60077-2, specifies:
a) the characteristics of the fuses;
b) the service conditions under which the fuses must comply, including:
– operation and behavior in normal service;
– operation and behavior in case of short circuit;
– dielectric properties.
c) the tests designed to confirm compliance of the fuse with its characteristics under the specified service conditions, and the methods to be employed for these tests;
d) the information to be marked or provided with the fuse.
This standard does not cover parallel connection of fuses.
During the preparation of this product standard, IEC 60269-1 and IEC 60282-1 were considered, with their requirements being as closely followed as possible.
This product standard refers to the general rules for electrotechnical components given in IEC 60077-2, but it provides direct reference to IEC 60077-1 for general conditions.
