400kV Senior Authorised Person

Role Overview

A 400 kV SAP is responsible for the safe operation, switching, isolation, and energisation of transmission‑level high‑voltage systems. This includes overseeing all HV activities, issuing safety documentation, and ensuring compliance with National Grid / TO procedures and site rules. The role is critical for maintaining safety, system integrity, and operational continuity on large‑scale transmission assets.

Key Responsibilities

• HV Switching Operations — Plan, execute, and authorise switching activities on 400 kV systems, including transformers, GIS/AIS switchgear, busbars, and overhead line interfaces.

• Safety Documentation — Issue and manage Permits to Work, Sanctions for Test, Limitation of Access, and other safety documents.

• Control of HV Isolations — Ensure all isolations are correctly established, locked, tagged, and recorded.

• Authorisation & Compliance — Work in accordance with National Grid Safety Rules, DNO/TO procedures, and project‑specific safety management systems.

• Outage Planning — Coordinate outages with the Transmission Owner, Control Room, and project teams.

• Commissioning Support — Support FAT/SAT, energisation, and commissioning of 400 kV assets including protection schemes.

• Contractor Supervision — Oversee HV subcontractors, ensuring compliance with method statements, RAMS, and safety rules.

• Fault Response — Lead HV fault investigations, switching, and restoration activities.

• Technical Assurance — Review drawings, switching schedules, protection settings, and test results.

• Reporting — Maintain accurate logs, switching records, and safety documentation.

Essential Requirements

• 400 kV SAP Authorisation

• Minimum 5+ years experience at transmission voltage levels (275/400 kV).

• Strong knowledge of NG Safety Rules, TO procedures, and HV operational standards.

• Experience with AIS and GIS switchgear.

• Competence in protection systems, intertripping, and commissioning interfaces.

• Ability to produce and review switching schedules and safety documentation.

• Strong understanding of CDM, HV safety, and control‑room coordination.