Data Centre – MV/HV Relay Commissioning Engineer (Protection & Control)
This is an excellent opportunity for an experienced MV/HV Relay Commissioning Engineer (Protection & Control) to join a well-established client delivering a hyperscale data centre commissioning programme. This role is highly specialised, focusing on medium and high voltage systems, protection schemes, and relay commissioning within mission-critical infrastructure.
Key Responsibilities
- Execute MV/HV relay commissioning (L2–L4) across critical power infrastructure within a live data centre environment
Commission and test protection relays across:
- Medium Voltage (MV) switchgear
- High Voltage (HV) systems and feeders
- RMUs (Ring Main Units)
- MV/LV transformers
- LV distribution boards and switchboards
- Perform primary and secondary injection testing on protection relays to verify trip characteristics and coordination
- Carry out end-to-end protection scheme validation, including interlocks, alarms, and tripping logic
Undertake HV and MV electrical testing, including:
- Insulation resistance testing (IR)
- Ductor (low resistance) testing
- HV withstand and pressure testing (where applicable)
- Commission and validate networked and integrated protection systems, ensuring correct communication between relays, SCADA, and control systems
- Work on MV switchgear installations within E-Houses, ensuring compliance with design and safety standards
- Interface with OEMs (including Siemens protection systems), Commissioning Authorities (CxA), and multidisciplinary site teams
- Follow structured commissioning procedures using digital platforms (e.g., BIM360 / ACC) and maintain accurate test documentation and reports
- Ensure all works are conducted in line with HV/LV safety rules, permits, and isolation procedures
Technical Requirements
- Strong background in Protection & Control engineering within MV/HV environments
- Proven experience in hands-on relay commissioning and protection scheme testing
In-depth knowledge of:
- Protection relays (overcurrent, differential, distance, etc.)
- MV/HV switchgear and distribution systems
Practical experience with:
- Primary & secondary injection test equipment
- Fault finding and relay configuration
- Demonstrable experience in HV and MV electrical testing methodologies
- HV/LV authorised person with a strong safety-first approach
- Ability to work effectively in live, high-risk, mission-critical environments
Preferred Experience
- Experience in data centres, utilities, or critical infrastructure projects
- Familiarity with Siemens, Schneider, or ABB protection relays
- Experience working with SCADA and networked protection systems
- Knowledge of structured commissioning processes and digital QA/QC systems