Slave Can Now Be Master

Feb. 1, 2004
Firmware updates for the vendor’s Allen-Bradley MicroLogix 1200 and MicroLogix 1500 controllers add Modbus Remote Terminal Unit master protocol capabilities.

This allows users in industries such as water, wastewater, oil and gas to easily integrate and standardize Supervisor Control and Data Acquisition (SCADA) networks, because MicroLogix can now be used at all levels of the Modbus network—master or slave. While MicroLogix has had slave capabilities for years, the ability for MicroLogix controllers to act as masters creates more controller flexibility and options, and a more streamlined solution for SCADA applications, the vendor says. Free to existing customers, the updates can be downloaded at All new MicroLogix 1200 and 1500 controllers will ship with the master and slave protocol capabilities.