The Emergency Overspeed Board (TCEA, is used for the high speed protection circuitry and is often referred to as the Protective Processor. These boards each bring in signals for high and low shaft speed, flame detection and automatic synchronization. The signals are scaled and conditioned and written over the IONET to the STCA board. The I/O Engine in the core uses the data from the three TCEA boards and performs a median select on the three values and the results are transferred across the COREBUS to the Control Engine. The TCEA boards send emergency trip signals to the Turbine Trip Board (TCTG), each TCEA board sends a trip signal to different relays.