Before switching off the Inmarsat C terminal you will need to 'log out'. When logging out your terminal it will transmit a message to the NCS reporting the terminal will not be available from that moment. This has to be done so the system knows the terminal is not available. If someone tries to send a message to this terminal the system will answer the sender that delivery will not be possible because the system knows the terminal is 'logged out'. No costs will be charged for this attempt. When the transceiver has been switched off without logging out, the LES will try five times to deliver the message. When it is not delivered after five attempts, the cost of a normal delivery will be charged to the sender of the message. So on board it's easy to switch off the terminal by pushing the on/off button without logging out, but in that case the Inmarsat system will not know the terminal is switched off and will try to deliver every message addressed to the terminal, and the costs will be charged to the sender without the message being delivered.

Practise on the Inmarsat C simulator

Switch off the terminal:

• Move in the 'Menu Bar' using the arrow keys to 'Options' and press 'Enter'.
  
• Go to 'Logout' using the arrow keys and press 'Enter'.
  
• The window will show: Confirm Logout Yes/No.
• Move to 'Yes' using the arrow key and press 'Enter'.
• Now the status field on top of the screen will show 'LOGOUT'.
  
• After approximately 25 seconds the terminal will have completed the logout process and it will show a window on the screen: logout successful Press 'esc' to continue!
• Now this has to be confirmed by pressing the 'ESC' bar.
• Now the status field on top of the screen will show 'Logged out'.
  
• The terminal will now be ready for switching off the power of the transceiver and the message terminal.