The Ship’s machinery systems are represented in diagrammatic form on the computer. On most views, the diagram of the system appears on the left, with controls on the right. With these controls, the system can be operated-
Machinery started and stopped, valves opened and closed, flow controllers adjusted, automatic temperature and pressure controllers set points altered etc- by means of the mouse.
Open valves and running machinery are indicated by a lighted green indicator on the diagram. The indicator not being Iit means that the valve is shut or the item of machinery is not running. If there is no indicator, it means that particular valve is not operable; i.e. it is permanently open .In some cases such as flow control valves, a numerical read-out will indicate, as a percentage, the extent to which the valve is open. This will correspond to the setting that you have chosen for that valve on the control panel. Temperatures and pressures are indicated numerically on the diagram, or by means of thermometers and pressure gauges on the control panel. Tank levels are indicated by a gauge glass on the tank. Most of the meters and gauges will indicate the alarm range, i.e. 'too low' or 'too high' in red, with the 'normal operating range’ in between as black or blue.
There are 'manual - auto' change-over- switches which enable you to control temperatures etc either manually, or automatically. When 'manual ' is selected, adjustment of the set point cannot be done as a 'set point is meaningless if the parameter is under- manual control. When ‘auto’ is selected the by-pass valves etc cannot be manually adjusted, as the computer will then control it. Initially, use the 'manual' setting on all controllers and learn to control the temperatures etc by manual use of the cooler flow control and by-pass valves.
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