Oil Filled Distribution Transformers Installation Technical Requirements

1. Column-Mounted Distribution Oil-Immersed Transformers

Core Safety Requirements

• Basic Distance: The minimum distance from the transformer to surrounding objects is ≤2.5m.
• Grounding Requirement: All iron components must be reliably grounded; the grounding height of exposed conductive parts is ≥3.5m.
• Fixation: The transformer base is fixed to a workbench, and the upper part is secured to utility poles with metal fasteners.
• Line Insulation: The upper and lower incoming/outgoing lines of the transformer must use multi-layer insulation.
• High-Voltage Dropout Fuse:
  • The minimum height from the fuse to the ground is ≥4m.
  • The minimum distance from the fuse to adjacent objects is ≥0.5m.
  • The angle between the fuse’s center line and the vertical line is 25°–30°.
• Warning Sign: Clearly hang a “No Climbing, High Voltage Danger!” warning sign.

2. Indoor-Installed Distribution Oil-Immersed Transformers

Core Safety Requirements

• Ventilation: The transformer room must have good natural ventilation to ensure heat dissipation.
• Fire Resistance Rating: The transformer room must meet Class I fire resistance standards.
• Clear Distances:
  • The minimum clear distance between the transformer’s front/rear/side surfaces and the room walls is ≥0.6m.
  • The minimum clear distance from the transformer to the room door is ≥0.8m.
• Doors and Windows:
  • Room doors and windows must open outward to facilitate emergency evacuation.
  • The lower part of doors and windows must be equipped with shutters for air circulation.

3. Ground-Mounted Distribution Oil-Immersed Transformers

Core Safety Requirements

• Foundation Height: The transformer foundation must be ≥0.2m higher than the ground; drainage channels must be installed around transformers in flood-prone areas.
• Surrounding Protection:
  • Brick or stone walls (not bamboo/wooden fences) must be installed around the transformer, with a height ≤1.8m.
  • The wall door must be made of fire-resistant materials, open outward, and be lockable.
• Platform Installation: The transformer must be installed on a platform with a minimum height of ≥2.5m.
• Spacing Requirements:
  • For two or more outdoor-installed transformers, the minimum distance between their outer surfaces is ≥1.25m.
  • The minimum distance from the transformer to flammable buildings is ≥5m.
  • The minimum distance from the transformer to fire-resistant buildings is ≥3m.
• Warning Sign: Clearly hang a “STOP, HIGH VOLTAGE DANGER” warning sign on the surrounding wall or installation platform.