Choose your region and language



Surge arrester MWK

Silicone-housed surge arrester of IEC class station low (SL) for AC systems up to 52 kV

MWK is a surge arrester with metal-oxide (MO) resistors without spark gaps directly molded in silicone housing, in grey color, designed and tested according to IEC 60099-4; it fulfills the requirement of ANSI/IEEE C62.11. Fire and smoke behavior tested and classified according to EN 45545-2.

It is used for secure protection of medium-voltage systems against overvoltages from atmospheric discharges and switching conditions.


  • Medium-voltage distribution transformer
  • Medium-voltage cable and cable termination
  • Medium-voltage capacitor and capacitor bank
  • Other medium-voltage distribution equipment

Why Hitachi Energy?

  • Over 100 years of experience in overvoltage protection and more than 30 years with silicone insulation
  • Local and global Hitachi Energy application support
  • Proven safe short-circuit current design
  • Design life of more than 30 years
  • Own production of metal-oxide (MO) resistors
  • Excellent protection level with low residual voltage
  • UV resistant  silicone housing with excellent pollution performance
  • Maintenance free

Brief performance data

Maximum system voltage (Us)  kV 52 52
Continuous voltage through arrester (Uc)  kVrms 4-44 8-44
Rated voltage of arrester (Ur)  kVrms 5-55 10-55
Nominal discharge current (In)  kApeak 10 10
Thermal energy rating (Wth)  kJ/kV (Ur) 5.0 5.0
Specified short-term load (SSL)  Nm 153 153
Creepage distance   Standard Long

Something caught your eye?

Our sales team will get in touch with you