1785-PFB Product datasheet   

1785-V40L Functional Description

 The 1785-PFB is a Profibus DP communication module from Allen-Bradley, specifically part of Series B of the PLC-5 Profibus modules. Designed for use with PLC-5 processors, this module facilitates high-speed data exchange between automation systems and remote I/O peripherals. Key features include a remote input-output scanner, an LED display, an RS-232 serial port, and an RS-485 interface. The 1785-PFB Profibus DP communication module  enhances communication efficiency through its DP master and DP slave units, where the master requests data from the slave, which then responds, ensuring smooth, organized data transfers. The module supports a cyclic communication mechanism, ensuring continuous database updates between devices.

One notable feature of the 1785-PFB Profibus DP communication module is its ability to detect and report duplicate station addresses between the DP master and slave units. However, caution is required when installing or removing the module, as it must not be done while the system is powered. Additionally, the module operates using a polling method, where the DP master unit sends out requests to slave units for I/O data exchange. The DP master must also manage a set of configuration data for each slave, which includes bus parameters and address assignments to enable proper communication on the Profibus network. This makes the 1785-PFB Profibus DP communication module  a vital component for efficient automation and data exchange in distributed systems.