Transfer Switches

Insulated Case Automatic Transfer Switches, 800 thru 4000 Amps

U.L. 1008 Listed (File No. E32008), these Insulated Case Automatic Transfer Switches are rated for application 800A to 4000 Amps, up to 600 Vac with interrupting ratings of 65kAIC@480Vac thru 150kAIC@480Vac available.




The Standard Insulated Case Automatic Transfer Switch (ATS) utilizes separate, internal spring charging motors, open coils and close coils, to operate both the normal and emergency insulated case units. Normally, the transfer switch operates on the preferred power source with the Normal insulated case unit in the closed position and the Emergency insulated case unit in the open position.


The Standard Insulated Case ATS provides dependable, positive, programmed delay transfer to an emergency power source in the event of normal power source failure.


The switch returns the system to the normal power source in an orderly fashion when normal power is restored. In the event that the emergency source fails, the switch will automatically return to the normal source when it becomes available.


All ATS are protected by mechanical interlocking located to the right of the insulated case units to prevent accidental paralleling of the sources except were temporary source paralleling is required. They are a Dead Front design with rear access for operator safety. Both Draw Out and Fixed Circuit Breaker designs are available. They are equipped with a manual charging handle, manual mechanical close/open pushbuttons and open/closed mechanical position indicators to safely operate the transfer switch manually.


This allows us the flexibility to offer in addition to a single ATS, a complete switchboard incorporating features such as:


  • Special bussing to close couple to bus duct.
  • Special bussing to close couple to existing switchgear.
  • Separate cable pull sections.
  • Front accessibility.
  • Side inspection access.
  • Utility metering sections.
  • Additional sections for related controls and monitoring.
  • Incorporation of monitoring and special protective equipment.