Installation of high-voltage cable trays in North Korea

High-voltage cable tray installation requires careful planning, proper materials, adherence to safety standards, and systematic execution to ensure reliability and safety.

Planning and Site Preparation

Before installation, review approved shop drawings detailing tray layout, lengths, and locations within electrical rooms, plant rooms, or service corridors. Inspect all materials upon delivery to ensure compliance with specifications, and remove any damaged or unsuitable items immediately. Cable trays and ladders should be stored horizontally on flat surfaces with timber supports at regular intervals to prevent deformation and protect from moisture and sunlight .

Material Selection

Choose cable tray materials based on environmental conditions and load requirements. Common options include aluminum, steel, or fiber-reinforced plastic (FRP). For high-voltage applications, ensure that conductors are rated for open-air environments, such as Tray Rated (Type TC) or Metal-Clad (Type MC) cables . Accessories and fittings must match the tray system and be compatible with high-voltage insulation requirements.

Installation Methodology

1. Tray Layout and Support: Install trays according to the approved design, maintaining proper alignment and slope for drainage if required. Supports should be spaced according to manufacturer recommendations to prevent sagging.
2. Cable Laying: Lay cables in an organized manner, avoiding excessive bending to prevent insulation damage. Maintain fill limits: power cables should not exceed 40% of tray cross-sectional area, and control cables 50% .
3. Separation and Grounding: Separate high-power and low-power cables to prevent electromagnetic interference (EMI). Metallic trays can serve as grounding conductors if they meet safety standards .
4. Fixing and Identification: Secure cables at regular intervals using approved clamps or ties. Label cables clearly for maintenance and future troubleshooting .

Safety and Compliance

Ensure adequate vertical clearance above trays (at least 12 inches) for maintenance access. Avoid installing trays in hoistways or enclosed spaces to maintain accessibility . Follow local electrical codes and international high-voltage installation standards to minimize risks such as overheating, fire, or mechanical failure .

Testing and Commissioning

After installation, perform continuity, insulation, and grounding tests. High-voltage systems may require specialized personnel for switching, testing, and commissioning to ensure operational safety and reliability . Document all inspections and tests for compliance and future maintenance.

Considerations for North Korea

While specific local regulations may not be publicly available, the above practices are universally applicable. Adjustments may be needed for local climate, material availability, and site conditions. Engaging experienced high-voltage installation teams with international expertise can help ensure project success .