Positive-negative Cage Off Load
Pad-mount transformers are available in various electrical and mechanical configurations. Pad-mount transformers operate on medium-voltage distribution systems, up to about 35 kV. The low-voltage winding matches the customer requirement and may be single-phase or three-phase.

Pad-mount transformers are (nearly always) oil-filled units and so must be mounted outdoors only. The core and coils are enclosed in a steel oil-filled tank, with terminals for the transformer accessible in an adjacent lockable wiring cabinet. The wiring cabinet has high and low voltage wiring compartments. High and low voltage underground cables from below enter the terminal compartments directly. The top of the tank has a cover secured with carriage bolt-nut assemblies. The wiring cabinet has sidewalls on two ends with doors that open sideways to expose the high and low voltage wiring compartments.

Three-phase pad-mounted transformers range in sizes from 75 kVA up to 5000 kVA with voltages ranging from 2,400 up to 34,500 delta or wye. Low-voltage pad-mounted range in size from 208y/120 through 24,940y/14,000.

Model Explanation
 WSL□ □/□-□╳□
    W:  off-circuit
    S :  three-phase
    L :  cage type
    □:  voltage regulation model  
    □:  rated current
    □:  rated voltage
    □:  number of tapping heads
    □:  number of tapping position 

Voltage Regulation Model
    I  :  linear regulating
    II :   central point
    III :  neutral point
   IV :  Y-△ conversion
    V :   series-parallel connection
   VI:   positive and negative regulation

Samples Technical Data