The Device Control block can fill a vat with substances from multiple sources. Assume the vat contains five valves that must be opened or closed based upon the status of the other valves, as shown in the following figure.
The Device Control block's WAITOR command ensures that Valve A closes before any other valve opens. By specifying digital output addresses in the block's dialog box, you can use output commands to open Valves B, C, D, and E according to your control scheme.
