Power Transformers

We offer a complete range of transformers designed to meet the needs of any industrial application.

Substation Transformers

These rugged transformers are ideal for substation yards and power distribution lines.

Pole Mount Transformers

Pole mounted transformers are the standard for single and three phase power distribution throughout much of the U.S. We carry many overhead transformers for large and small utility applications. We specialize in selling pole mounted transformers to non-utility customers in the commercial and industrial arenas.

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Capabilities

Maddox Liquid Filled Distribution Substation and Power Class Substation Transformers are designed, built and tested to the highest industry standards including NEMA, ANSI C.57, DOE and IEEE as applicable. With a range of customizable features, Maddox substations can be configured to maximize performance, minimize potential arc flash exposure and address environmental concerns. All designs can be supplied with full or partial length air terminal chambers for ease of installation.

Product Definition

  • ‍300 kVA – 30,000 kVA base
  • Up to 115kV

Technical Specifications

Standard Specifications

  • Type II PCB-free mineral oil (ONAN)
  • High quality silicon steel core
  • Aluminum windings (distribution class)
  • On-load tap-changer
  • Reinforced carbon steel tank
  • Lifting lugs
  • Externally fastened high and low voltage bushings
  • Pressure relief valve
  • Vacuum gauge
  • Liquid Temperature indicator
  • Liquid level indicator
  • Drain and sampling valve
  • Schrader valve
  • Ground pads

Optional Features

  • Environmentally friendly high flash point
  • FR3 (KNAN) oil
  • Copper windings
  • On-load tap-changer
  • Stainless steel tank
  • Meters with contacts
  • Auxiliary control cabinet
  • Winding temperature indicator
  • Fan package (ONAN)

Capabilities

Pole-mount liquid-filled transformers are designed, built, and tested in accordance with all applicable IEEE standards. Each unit is built to meet the latest DOE efficiency regulations. They are ideal for utility applications requiring single-phase and three-phase distribution.

Product Definition

  • 5 kVA–333 kVA
  • High Voltages: 2400 to 34 500 (up to 150 kV BIL)
  • Low Voltages: 120

Technical Specifications

  • Standard Specifications
  • Type II PCB-free mineral oil (ONAN)
  • 65°C temperature rise
  • Mild steel tank
  • Corrosion resistant paint finish
  • Lifting points
  • Low voltage side bushings
  • High voltage deck mounted bushings
  • All standard tap configurations available
  • Grounding provisions
  • Anodized aluminum or stainless steel ANSI 70 gray nameplate
  • Paint color
  • Aluminum windings
  • Suspension brackets
  • Lightning rod mounting pads
  • Cover grounding strap

Optional features

  • High voltage taps (external lever handle or hook handle)
  • Dual voltage
  • Pressure relief device
  • Internal fuses
  • Switches
  • Secondary circuit breaker
  • Lightning rods
  • Environmentally friendly, high flash point FR3 oil
  • IFD (internal fault detector)
  • Copper windings
  • Stainless steel tank