ZnO Series Block

HVR zinc oxide varistors are designed for specific applications.

HVR zinc oxide varistors are designed for specific applications and should not be used for purposes not identified in our datasheets and application notes unless otherwise agreed with HVR during the design phase. For applications in line-to-ground circuits based on various international and local standards there are restrictions existing or additional safety measures required.

Key features of the ZnO series block

  • High performance
    • Wide operating voltage range 95 … 1100 Vrms
    • High surge current ratings up to 100 kA
    • No derating up to 85 ° C
    • Excellent protection Level
  • Highest flexibility
    • Special operating voltages according to customer requirements are possible
  • Design service
    • Design service including technical drawing to international standards


  • Over-voltage in the mains, caused by lightning, inductive or capacitive coupling
  • Consumption in switch contacts with inductive load
  • Limit over-voltages in transformers, motor, generator winding and magnet coils