The purpose of this part of IEC 60077 is to give additional or amended rules for high voltage fuses as a supplement to those given by IEC 60077-2. NOTE In this product standard the term high voltage fuses is used in the context of the voltages used in the field of railway rolling stock. The high voltage fuses concerned are those to be connected into power and/or auxiliary circuits. The nominal voltage of these circuits lies between 600 V d.c. and 3 000 V d.c., according to IEC 60850. These fuses may also be used in auxiliary a.c. circuits up to a nominal voltage of 1 500 V. NOTE Certain of these rules may, after agreement between user and manufacturer, be used for fuses installed on vehicles other than rail rolling stock such as mine locomotives, trolleybuses, etc. This product standard together with IEC 60077-2 states specifically: a) the characteristics of the fuses; b) the service conditions with which the fuses have to comply with reference to: – operation and behaviour in normal service; – operation and behaviour in case of short circuit; – dielectric properties. c) the tests intended for confirming the compliance of the fuse with the characteristics under the service conditions and the methods to be adopted for these tests; d) the information to be marked on, or given with, the fuse. This standard does not cover parallel connection of fuses. During preparation of this product standard, IEC 60269-1 and IEC 60282-1 have been considered and their requirements have been kept as far as possible. This product standard makes reference to the general rules for electrotechnical components given in IEC 60077-2, but for general conditions reference is made directly to IEC 60077-1