About Tru-Block

Company Timeline

  • April 1989
    • Zero Surge Inc. is incorporated to manufacture high performance filters which suppress surges and noise but do not degrade with use or fail.
  • September 1989
    • U.S. Patents # 4,870,528 and 4,870,534 issued for “Series Mode” power quality filter technology.
  • June 1990
    • Zero Surge’s Chief Engineer, J. Rudy Harford, selected as Inventor of the Year by the New Jersey Inventors Congress and Hall of Fame for his contributions to the surge suppression field.
  • June 1999
    • Overall product line redesigned using shielded, encapsulated inductors.
  • August 1999
    • Zero Surge filter technology is certified to 1,000 worst-case surge endurance (6,000 Volts/3,000 Amps) with only a 330 SVR (let-through voltage) by Underwriters Laboratories under their optional performance testing program and qualifying the technology to the highest US Government CID rating of Grade A, Class1, Mode 1.
  • April 2004
    • U.S. Patent # 6,728,089 is issued for Zero Surge’s Spectrum® Wide Voltage Range technology, making it compatible with the very wide voltage range of switch-mode power supplies. It is now ideal for use with generators and in brownout conditions.
  • April 2005
    • J. Rudy Harford again selected as Inventor of the Year by the New Jersey Inventors Hall of Fame and the Research & Development Council of New Jersey for the development of  surge cancellation technology (the only engineer to receive this distinction twice).
  • June 2005
    • U.S. Patent # 7,184,252 is issued for Zero Surge filter technology used with isolation transformers.
  • June 2006
    • U.S. Patent # 7,068,487 is issued for Zero Surge advanced surge suppression.
  • December 2006

    • Zero Surge receives Electronic Products Magazine’s “Product of the Year Award” for the development of advanced surge suppression technology.
  • May 2011
    • Zero Surge introduces the Tru-Block® product line with 1,000 surge endurance, 330V suppression rating, and 10 year warranty/connected equipment policy as a safe, effective, and reliable alternative to MOV whole building surge suppression systems.