GE (General Electric) created the DS3800NPAC PCB, or printed circuit board, for the control of turbines. This device is a part of the MKIV. The Mark IV is part of the Mark series of turbine systems. The Mark IV system regulates gas and steam turbines and automates their processes. Fuels are controlled between the turbine system’s speed and load control requirements. Mark IV controls cooldown and shutdown as well as temperature, automatic startup, and the injection of steam and water. The Mark IV protects the turbine equipment and the people who operate it. The Mark IV features built-in diagnostics. The repair and troubleshooting of the turbines are made easier due to the diagnostics. Since the late 60s, when the first Mark I system was developed, the Mark systems have been used for the control of turbines. The processes the Mark systems were based on have been developed since the late 1940s. These processes were developed with the help of newly available technology introduced throughout the years. Over forty years of operational success and decades of refinement and learning led to the creation of the Mark IV system. The Mark IV system fulfills all of the requirements of controlling turbines as well as the turbine’s auxiliary functions. The Mark IV utilizes what were then state of the art technologies. A communicator, a device which communicates between the turbine control and the operator interface, is featured with the Mark IV. The system also has a backup LED display for use if the microprocessor or CRT fails.