Three Phase Pole Mounted Transformers

The low-voltage (LV) assembly with 4-hole spade terminals provides the output connection point for delivering stepped-down voltage from the transformer’s secondary windings to the customer or distribution system. It is built for high current capacity and secure bolted connections.

• Location: Mounted on the lower portion of the transformer tank or on the front plate, typically near the nameplate and grounding provisions.
• Layout: Comprises insulated bushings leading to copper or aluminum spade terminals with four precision-drilled holes, allowing for bolted cable lugs or bus connections. Each terminal corresponds to one phase of the three-phase secondary circuit.
• Function: Enables safe, low-resistance transfer of electrical energy from the transformer to the load circuits. The 4-hole spade design ensures tight, vibration-resistant connections that support efficient current flow and minimize heating at contact points.

The ground pad with eyebolt connector provides a secure grounding point to ensure the transformer tank and core are safely bonded to earth potential. This component protects against electrical faults, lightning strikes, and static charge buildup.

• Location: Mounted on the exterior lower section of the transformer tank, typically near the low-voltage bushings or base plate for easy access during installation.
• Layout: Consists of a flat, conductive grounding pad connected to the tank, equipped with an eyebolt-style terminal for attaching ground conductors. The assembly is designed for durability and corrosion resistance to maintain long-term conductivity.
• Function: Establishes a reliable path to ground for fault currents and stray voltages, ensuring safety for personnel and equipment. The eyebolt connector allows for simple, secure attachment of grounding cables using standard lugs or clamps.

The nameplate bracket provides a fixed mounting point for the transformer’s identification plate, which displays essential information such as kVA rating, voltage, serial number, and manufacturer data. This ensures the unit’s specifications remain clearly visible for maintenance and inspection.

• Location: Mounted on the front or side of the transformer tank, typically near the low-voltage terminals or operating accessories for easy readability from ground level.
• Layout: A welded or bolted metal bracket designed to hold an engraved or printed aluminum or stainless steel nameplate. The bracket positions the plate at an angle or flat against the tank surface, depending on transformer configuration.
• Function: Maintains secure and visible placement of the transformer’s identification information, protecting it from environmental wear and ensuring compliance with utility and safety labeling standards.

The transformer tank serves as the main enclosure that houses and protects the internal active components, including the core, windings, and insulating fluid. It provides both mechanical support and environmental sealing for long-term reliability in outdoor conditions.

• Location: Central structure of the transformer, forming the body to which all external fittings, bushings, and accessories are mounted.
• Layout: Constructed from heavy-gauge steel, the tank is fully welded and designed to be oil-tight. It includes structural reinforcements, lifting lugs, drain valves, and mounting points for accessories such as radiators, gauges, and nameplates.
• Function: Contains and protects the transformer’s internal components while holding the insulating and cooling oil. The sealed design prevents moisture intrusion, maintains dielectric integrity, and ensures pressure stability under varying thermal conditions.