Fairbanks 
Smart sectional controller.
Multiplex and digitizing two analog load cells onto a multi-drop RS-485 bus.
Each cell is provided with 6.3 VDC excitation voltage.
The output is connected to its own load cell input circuit that contains a separate gain stage and analog filter circuits.
The filtered outputs are multiplexed into the input of a 24 bit A/D converter that is monitored by a micro-processor, which controls the multiplex.
It applies additional signal processing such as digital filtering.
The processed load cell signals are then available on the RS-485 bus via a special protocol.