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Manual 35018V1
505XT Digital Control System for Steam Turbines
Woodward
161
There is a Screen Saver function that is invoked after a period of inactivity. It is defaulted to 4 hours
(adjustable in Service / Screen Settings) – when this comes it a small version of the ‘Splash Screen’ will
bounce around on the screen. Press any key to revive the display (maroon keys are recommended).
When awaking from screen saver the user login level will be reduced to Operator. This also is adjustable
in Service / Screen Settings if desired, it can be changed to awaken to Monitor.
Control Mode Architecture
Basic control program architecture is illustrated in Figure 5-1. The 505’s normal operating architecture
divides the control into two states.
Run – which includes Operation and Calibration modes
Program - Configuration mode
Pressing the MODE key at anytime will open the Login and Mode Screen
The Configuration Mode is used to configure the 505 for the specific application and set all operating
parameters (see Chapter 4). In this mode the control will issue an IOLOCK (LED) and the state of all
Outputs from the 505 are disabled. This means that all Relays are de-energized and all Analog/Driver
outputs are at zero current. Initially all 505’s must be placed in this mode to enter a valid configuration of
the I/O and functions desired for the specific turbine application.
The Calibration Mode is used after the configuration of the 505 is complete. It is used to perform
calibration of signals, verification of speed signals and the forcing of outputs of the control in preparation
to run the turbine. All I/O is functional in this state. To enter this mode the turbine must be TRIPPED
(LED).
The Operation Mode is used to view operating parameters and run the turbine. This is the typical mode
the control uses and is the default mode it enters at Power-up. All I/O is functional in this state. The
turbine may be either running or not running in this mode.
Figure 5-4. Control Mode Architecture