Each ConveyLinx Module communicates to its adjacent modules and to any connected PC or PLC via Ethernet physical media. ConveyLinx Modules recognize (3) TCP/IP based protocols: Modbus TCP, Profinet I/O, and Ethernet I/P. Modbus TCP is the “native” protocol for communications between ConveyLinx Modules and the EasyRoll PC software. When ConveyLinx Modules are used even for basic ZPA control with no external connections to a PC or PLC, they utilize Modbus TCP for inter-module communication. Ethernet I/P is recognized by ConveyLinx Modules and any given ConveyLinx Module can be attached to an Ethernet I/P capable PLC (Allen-Bradley ControlLogix or CompactLogix platforms) and be recognized as a Generic Ethernet Module or explicitly as an ConveyLinx Module by using a Pulseroller provided EDS file. Profinet I/O is recognized by ConveyLinx Modules and can be attached to any Profinet I/O capable PLC (applicable Siemens platforms) using a Pulseroller provided GSDXML file.
Each ConveyLinx Module’s internal data structure is arranged and addressed as Modbus Holding Registers. The on-board communication and control processes attach logical meanings to each holding register and read and write data to specific registers to initiate and/or react to events. Certain registers contain information as to how the ConveyLinx Module is configured (MDR type, speed, direction, etc.) for its local controls. Other registers are used for inter-module communications for conveyor operation. For example, when an upstream ConveyLinx Module has a Carton ready to discharge to its neighboring downstream ConveyLinx Module, the upstream ConveyLinx Module will write a specific value to a specific address in the downstream ConveyLinx Module’s internal registers. The downstream ConveyLinx Module’s on board logic monitors these registers and knows that a specific value means that an upstream Carton is coming and to engage the proper control logic to convey the Carton.
Because ConveyLinx utilizes an open architecture (Modbus TCP) for inter-module communications; with proper definition and expected usage of certain register address locations, external control devices (PC’s and PLC’s) can easily interact with ConveyLinx Modules to monitor and control various points along the conveyor path.