Each ConveyLinx communicates to its adjacent modules and to any connected PC or PLC via Ethernet physical media. ConveyLinxs recognize (3) TCP/IP based protocols: Modbus TCP, Profinet I/O, and Ethernet I/P. Modbus TCP is the “native” protocol for communications between ConveyLinxs and the EasyRoll PC software. When ConveyLinxs 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 ConveyLinxs and any given ConveyLinx 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 by using a Pulseroller provided EDS file. Profinet I/O is recognized by ConveyLinxs and can be attached to any Profinet I/O capable PLC (applicable Siemens platforms) using a Pulseroller provided GSDXML file.
Each ConveyLinx’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 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 has a Carton ready to discharge to its neighboring downstream ConveyLinx, the upstream ConveyLinx will write a specific value to a specific address in the downstream ConveyLinx’s internal registers. The downstream ConveyLinx’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 ConveyLinxs to monitor and control various points along the conveyor path.