There are three essential applications (services) that run on the PC. Two of these are maintained by the system tray application. The details can be expanded by clicking on the Batrium icon in the system tray (bottom right of PC screen).
The System Controller background service is the heart of the PC processing for all messages and storage of information related to the attached devices. The ServiceCentre connects to this via the PC network (even if the ServiceCentre is on the same PC). This means that ServiceCentre is a slave to the System Controller.
The System Controller has a unique system number that is used when accessing all information. The ServiceCentre searches the network for System Controllers (see Configuration => System Selector menu). Once a system has been selected, all interaction by the ServiceCentre is via this System Controller. The user can also type in a description to make the system number more meaning full when choosing it from multiple items on the network (See separate documentation on commissioning).
The System Controller stores all the data required to interact with the connected hardware. This is called the “System Architecture”. The architecture is generated through the ServiceCentre Commissioning Setup Wizard. It is viewed and can be manually set through the Advanced Settings menus. This architecture can be backed up and restored through the ServiceCentre (Tools => Backup/Restore menu).
The System Controller uses the UMon Hub that has been allocated/joined to it (connected PacMon and/or UMons). It only makes sense for this to be UMon hub on the same PC that the System Controller is on.