• Powell subsurface/vault style medium voltage switches are available for systems rated 15kV through 38kV, 900A continuous current. Subsurface vault switches utilize a medium voltage switch assembly mounted below ground level in a vault or chamber. These are typically used for underground distribution systems and a straight-forward and simple method of system distribution. A wide variety of switch configurations are possible so as to provide a truly custom-engineered solution for your application.

  • Powell subsurface vault style switches are application where an underground distribution system is used. The switch assembly by nature is exposed to wet or submersible situations. Utility applications are the most common and the Powell switch design offers a wide range of flexibility.

    Call Powell today to discuss your needs for custom-engineered subsurface vault switch applications.

  • Powell underground distribution switch enclosures are ¼ inch mild steel or stainless steel tank.  Powell SF6 devices are constructed and tested to a leak rate of 1X10-6 cubic centimeters per second leak rate. Each and every Powell SF6 device is pressurized with helium to 13 PSIG then tested using a helium mass spectrometer. Due to the fact that the molecule of helium is 4.9 times smaller than SF6 and that the test pressure is 2 times greater than the normal operation pressure the leak rate of SF6 will be much improved over the leak rate of the helium test gas.

  • Powell’s experience in the SF6 underground distribution switch applications enable us to be able to integrate our load break, fault interrupter, source transfer devices into your existing system. Examples of such integration are:

    • Retrofit existing transformer mounted switches
    • Connect new SF6 switch to existing lead and paper cable
    • Assist in conversion to smart grid automation


  • The Powell Team is dedicated to supplying an entire portfolio of distribution switch products to meet the specific needs of your application and to ensure that customers and end users receive equipment that is of the highest quality and reliability. Our technical staff is ready and available for consultation to establish the final product configuration that will conform to your most specialized needs.

  • Description
    ​SF6 Switch Tank ​1/4" welded mild steel tanks with stainless option, all external parts are corrosion resistant
    ​Switch Assembly ​Stored energy, highly durable, design tested for 2000 operations
    ​Unitized Blades ​Three-pole assembly is self-supported and self-aligned
    ​ ​
    ​Maximum Voltage Frequency BIL Load Interrupting Current Continuous Current
    ​15.5kV ​50/60 Hz ​95/110kV ​600A ​ ​600A
    ​27kV ​50/60 Hz ​125kV ​600A ​ ​600A
    ​38kV ​50/60 Hz ​150kV ​600A ​ ​600A

    Have a question? Let us know.