Insulated working under impressed voltage conditions (NSI5 equivalent for contractors)

Course details

This EUSR-endorsed training equips utility contractors with the skills to safely perform insulated working on HV and LV cable systems under impressed voltage conditions, in line with National Grid’s NSI‑5 technical guidance. Ideal for those working on overheard line-connected cable routes, the course combines theoretical instruction and practical, scenario-based learning to manage fault, induced, capacitive, and EPR hazard awareness.

Who Should Attend This Course?

• HV/LV cable contractors working with systems under impressed voltage
• Competent Persons seeking EUSR NSI‑5 endorsement
• Site personnel involved in insulated working environments
• Utility engineers and supervisors managing NV/LV cable sheath or accessories

What you will learn

• Definition and risk factors of impressed voltage conditions
• Regulations and management systems under NSI‑5 and National Grid Safety Rules
• Hazard recognition: induced voltage, dielectric polarization, EPR, stray currents
• Insulated and earthed working protocols, bonding, spiking, cable sheath tests
• Use of insulated PPE: platform, boots, gloves, tools, mats
• Permit processes, safety documentation, and competent oversight

Course Contents

• Impressed Voltage
• Purpose and Scope
• Definitions
• Dangers
• General Requirements for Work on Cable Systems
• General Requirements for Work on LV Cables
• General Principles for Work on HV and LV Cables Subject to Impressed Conditions
• Work on HV Cable Sheath Disconnecting Link Boxes and Link Pillars under Impressed Conditions
• Procedure for Cable Serving Test under a Permit for Work
• Work on Metallic Cooling Pipes under Impressed Conditions
• Work on or near Faulty or Damaged HV and LV Cables
• Assessment

Assessment & Certification

Delegates will be evaluated through a combination of practical exercises, oral questioning, multiple-choice assessments, and written responses, ensuring a comprehensive understanding of the course material.

Upon successful completion of the course and assessment activities, delegates will receive their results and be issued with a formal in-house certificate of achievement.

This certification is valid for a period of one year from the date of training.

Prerequisites

National Grid Competent Person Substations NSI 6 and NSI 8 and a good understanding of cable systems.

Benefits of This Course

• Demonstrates contractor-level NSI‑5 competence
• Supports safe, compliant live cable work in utility environments
• Ideal for HV/LV cable tasks near overhead lines
• Satisfies National Grid and EUSR utility compliance standards

Frequently Asked Questions

Q: What is NSI 5 and why is it needed?
A: It covers hazards and safe work methods for cable systems under impressed voltage, essential for safe operation in live utility environments.

Q: Is this course accepted by National Grid?
A: Yes, it aligns with National Grid’s NSI 5 technical guidance and is EUSR endorsed for contractors.

Q: Who needs NSI 5 certification?
A: Contractors working on or near HV/LV cables under impressed voltage, especially where cables run alongside live overhead lines.

Q: How often do I need to renew NSI 5?
A: Certification is valid for 1 year; a refresher required to maintain compliance

You might also be interested in the following courses

• EUSR Impressed Voltage Awareness
• EUSR - Impressed Voltage for Designers & National Grid Supplier Requirements (SR/234) Overview Training
• EUSR - Impressed Voltage for Managers & National Grid Supplier Requirements (SR/234) Overview
• EUSR - Impressed Voltage for Managers & National Grid Supplier Requirements (SR/234) Overview & IVDE (ECP/EAP) Training
• Requirements of The Electricity, Safety, Quality and Continuity Regulations (ESQCR) 2002
• NSI9 Testing High Voltage Equipment

If you have any questions about this or any other course, please get in touch on 01926 674340