1785-BEM Product datasheet  

1785-BEM Functional Description

The 1785-BEM Back-up Communication Exp Module PLC-5 Backup Communication Module by Allen-Bradley is designed to provide reliable communication backup and high-speed data transfer between two connected PLC processors. Installed in a single I/O slot on the 1771 chassis, the 1785-BEM Back-up Communication Exp Module ensures that processor data is securely backed up, preventing data loss during system failures. With a current draw of 0.6A at 5V DC, the 1785-BEM Back-up Communication Exp Module supports 32-bit input capability on the processor's image table for enhanced processing power.

This 1785-BEM Back-up Communication Exp Module features a switch assembly with four adjustable switches for easy configuration, as well as a field wiring arm (26-14 AWG) that ensures secure and reliable connections. The module is equipped with the 1771-CD cable connector for DH+ and Remote I/O (RIO) communication, supporting a communication speed of up to 1.2 Mega Baud. It also includes a factory-installed 0.25A relay at 24V DC for added functionality.

The 1785-BEM Back-up Communication Exp Module ensures seamless keying to the backplane via specific pin connections and comes with CE, UL, and CSA certifications for safety and compliance. Its operating temperature range is from 0 to 60°C (32 to 140°F), and it has a storage temperature range of -40 to 85°C (-40 to 185°F). The 1785-BEM Back-up Communication Exp Module is an essential addition for ensuring high availability and reliability in industrial control systems.

On the front panel, the 1785-L80B Controller Module features status indicators like PROC, FORCE, and COMM to provide real-time feedback on the controller’s operation. These indicators, along with the four communication channels, make the 1785-L80B a versatile and reliable choice for complex automation tasks.