Dynamic development of Programmable Logic Controller (PLC) technology and Supervisory Control and
Data Acquisition (SCADA) software has resulted in their widespread usage in integrated systems of automa-
tion, becoming one of the main directions of ship automation. This change justifies the need to improve the
training of future crews on simulators built with the use of PLC and SCADA technologies. This paper presents
a simulator prototype for selective processes ofa main-propulsion boiler’sfuel-gas-line nitrogenpurging system,
applied in LNG (liquefied natural gas) ships.Control algorithms and appropriateschematic diagrams of the
LNG fuel system of these processes werealso presented. A Versa Max Micro-series PLC and an InTouch 9.0 PL
SCADA software were applied in construction of the simulator. As a result of simulations, a visualisation of
different states of fuel line in the form of screenshots was included. Finally, the paper contains a concept for
simulator development based on hardware (sensors and actuators) without significant changes in existing so-
ftware; further development will providethe simulator with more similarities to a real ship system.
