The SA bus connects CH-PC controllers to endpoint devices, such as CH-PCX Expansion I/O Modules, network sensors, FX-DIS Local Controller Displays, and Johnson Controls Variable Speed Drives (VSDs).
On an SA bus, a CH-PC controller is the bus supervisor. The SA bus is a private MS/TP bus that only supports those devices that can be defined using the Controller Configuration Tool (CCT) programming tool. The bus does not support bus segments (Figure 1). See SA Bus Rules and Specifications for more information.