The Scan Bus mode is used to initiate, monitor, and interrogate controllers on the FC/SA bus. In this mode, the FIT communicates with the controllers to read their attributes. The Scan Bus mode is used when there are communications occurring on the bus or if there are no communications occurring. If no communication is occurring, do not initiate the Scan Bus mode until you verify that the idle bus voltage readings are at their desired levels on each bus segment. See Idle Bus Voltage Levels and the Voltage Menu section for more information. Selecting Scan Bus initiates communications to all devices on the bus. A correctly installed bus scan completes within a couple of minutes.
In the Scan Bus mode, the FIT monitors communications and interrogates controllers to report:
- The number of devices online
- The address of each device online
- The communication bus voltage levels of the device
- Status of EOL termination switch on the device