There are 2 methods:

Method1: This option is completely silent. It uses the default CitectSCADA settings. It installs Citect in the default folder C:\Program Files\Citect\CitectSCADA\...

Command to use: "D:\Disk1\setup.exe" quiet

Method2: This option will prompt you for a reboot and you will need to click "No". You will also need to create a setup.ini to customise the installation.

Command to use: "D:\Disk1\setup.exe" -ini:C:\TEMP\setup.ini

Example Setup.ini:

[setup]
ShowWelcome=0
ShowLicense=0
Folder=Citect550
Path=c:\citect\citect550
reboot=0

Note: This ini will run silent with no dialogs, will create the start up menu folder Citect550, install into c:\citect\citect550 and not reboot when complete.