The PPU 300 Paralleling and Protection Unit is a highly configurable controller designed for marine use. The controller contains the functions required to protect and control a generator and its breaker (specifically, a diesel generator, a shaft generator, a shore connection, or a bus tie-breaker). You can connect up to 12 controllers to create one system, with load-sharing sections. Typically, a PLC or operator will send commands to the PPU 300 to close or open the breaker. For a diesel generator, the PLC or operator can also send commands to start or stop the generator, change the regulation mode, and change the regulation set points. The controller display unit can have push buttons for the operator to change the controller mode, close and open the breaker, and start and stop a diesel generator. The color graphic screen shows status and info messages. The screen also allows fast access to live data, and alarm management. With the right authorization, the operator can also check and/or change the IO and parameter configuration. The light indicators of the display unit show the system status.