NG TS 3.07.30 PDF

This Specification defines the technical requirements within a Substation Control System to support Sequential Isolation of a disconnector following Circuit Breaker operation. The requirements can be achieved by either traditional hardware systems or software based systems making use of main plant auxiliary contacts. This Specification defines the functional, performance and safety requirements of software based Sequential Isolation systems to be applied at The National Grid Company plc (NGC), substations using Substation Control Systems.