When setting up the Modbus RTU Master/Slave over an RS485 network, a three-wire cable is required to connect back to the interface converter. The Simple NULL Modem cable with external +24 vdc power is recommended, but the Allen-Bradley 1761-CBL cable is also functional. To begin, plug the cable to the round eight-pin mini DIN receptacle and set the P10 Jumpers for RS-485 on the Catalyst. Parametric changes are also required within the RSLogix 500 and Alarmware to synchronize the Modbus Drivers. Here are the steps: 1. Connect the MicroLogix to your PC using the required 1761-CBL cable ... Continue Reading

The Verbatim Gateway system—interfaced with an Allen-Bradley MicroLogix family of PLCs containing a native Modbus RTU Slave driver—performs alarm and monitoring functions with existing wiring to PLCs as inputs via data communications. In order to facilitate data communications via Modbus RTU Master/Slave over RS232 data interface, RACO provides a NULL Modem serial cable, VAB-1. This cable has the RJ-45 connector required for the system. Below are instructions on how to integrate MicroLogix to Verbatim Gateway via Modbus Protocol over RS232. Communication setup for Allen-Bradley Mi... Continue Reading

Interfacing RACO’s Catalyst  system with Allen-Bradley’s MicroLogix PLCs allows Catalyst to use existing wiring for alarm notifications and data logging. The following tips will get you started: 1. Assemble your components: For proper setup, you will need RACO’s Catalyst system and Alarmware software, Allen-Bradley’s MicroLogix PLC and RSLogix software and the coordinating cables from each company. 2. Set up MicroLogix communications: Connect MicroLogix to your PC with the cable, then launch the RSLogix software. Using the software, set the communications driver to Modbus RTU sl... Continue Reading