The Circuit Breakers and Disconnecting Switches 2, Model 3783-A, consists of 3 three-phase circuit breakers and 9 three-phase disconnecting switches, enclosed in a full-size EMS module, that can be used to implement electric power substations with different switching schemes. Each circuit breaker and each disconnecting switch can be operated independently using dedicated I/O (open/close) switches or open/close control inputs on the front panel. An Ethernet port on the module front panel allows all circuit breakers and disconnecting switches to be controlled independently using a SCADA system. Green (close) and red (open) pilot lights on the front panel indicate the state of each circuit breaker and disconnecting switch. Open/close auxiliary contact sets are provided for each of the 3 circuit breakers. Open/close auxiliary contact sets are provided for one of the disconnecting switch. Module operation requires 120 V dc power which is applied to the module via two safety banana jacks on the front panel. Electric power substations with the following switching schemes, i.e., the bus (busbar) arrangements, can be implemented using two Circuit Breakers and Disconnecting Switches modules (Models 3783-0 and 3783-A):

• Single Bus

• Double Bus, Single Breaker

• Main Bus with Transfer Bus

• Ring Bus

• Breaker-and-a-Half

• Double Bus, Double Breaker