Lightning Protected Transformer


The Lightning Protected Transformer virtually eliminates transformer failure due to lightning. An UltraSIL Housed Polymer Evolution arrester or gapless VariSTAR porcelain arrester, designed by Cooper, provides overvoltage protection. Cooper’s STORM TRAPPER high-energy arrester, a low-voltage distribution arrester, is mounted directly to the transformer secondary windings, protecting the transformer from failures caused by secondary induced surges. A properly coordinated D-Link fuse by Cooper provides superior over-current protection.

kVA 5-167
Primary Voltage 2400 - 34,500 V
Secondary Voltage 120-600 V


  • Envirotemp™ FR3™ fluid
  • Electrical grade mineral oil available upon request
  • Meet or exceeds ANSI and NEMA standards
  • Meets DOE Energy Efficiency Standard 10 CFR Part 431 for distribution transformers
  • EPRI recommended interlaced core-type design (5-75 kVA)
  • Tank coating exceeds ANSI C57.12.31
  • Cover with a minimum dielectric strength of 8 kV
  • Tin-plated high and low-voltage bushing terminals to accommodate aluminum or copper conductors
  • Laser-engraved nameplate
  • Wet process porcelain high-voltage bushings resistant to high-voltage corona
  • Tank grounding provisions
  • Heavy-duty lifting lugs and hanger brackets per ANSI requirements1
  • Visible cover ground on units with cover-mounted bushings
  • Recessed tank bottom that offers protection when sliding over rough surfaces
  • Automatic pressure relief device
  • Polymer low-voltage bushings (5-75 kVA)
  • Arrester mounting and grounding provisions
  • Internal mark indicating the proper oil level
  • Permanently stamped secondary leads to ensure proper identification
  • Corrosion-resistant cover band
  • Quality System ISO 9001 certified
  • Optional MagneX Interrupter

Envirotemp™ and FR3™ are licensed trademarks of Cargill, Incorporated.