scope:

Sections 1, 2, 3 and 4 of this European Standard cover particular requirements for surge arresters for specific use in fixed installations of d.c. traction systems. These are surge arresters consisting of one or more non-linear resistors which may be in series with single or multiple spark gaps. Low-voltage limiters are covered under section 5. These are protective devices mainly used in fixed installations of d.c. traction systems to connect certain portions of the circuit, when, owing to an abnormal situation, the voltage across the device exceeds a predetermined limited value. They may be associated with other devices such as contactors for self-restoring arrangements.