chain of pumps with a jumper the system controller provides a user interface stores process formulas and displays system alarms and status indicators as well as serving as the master controller for the serial data busses to dispense chemical products according to a stored formula e g a product dispensing profile for a particular process the system controller sends data to one or more the pumps indicting the amount of chemical product that the pump stand is required to dispense the system controller also periodically interrogates the pumps to verify that the pumps are operating properly to this end the system controller will typically query the status of a network node before issuing a command the system controller may thereby obtain positive verification that the node is operating properly before issuing a command the system controller may also include a serial data port configured to communicate with an optional network gateway when present the network gateway provides a data link between the system controller and an outside network such as the internet so that system operators may communicate with one or more system controllers from a remote location to support the serial data bus network each pump stand includes a pump controller that provides local control of the pump motor and enables a data link process with the.