1757-SRM | Allen-Bradley | Redundancy Module

Description

The Allen-Bradley 1757-SRM is a high-performance system redundancy module designed for industrial automation, part of the ControlLogix and ProcessLogix PLC product lines. Its core function is to enable controller redundancy, achieved by pairing with a 1756-SRM module in a separate ControlLogix chassis to sync primary and secondary controllers, significantly boosting process system availability. This 2-slot module features integrated fiber ports, compatible with 62.5/125 micro-meter multi-mode fiber cables with SC-type connectors.

Key technical specifications include a 220V operating voltage, 166 MHz clock frequency, and support for up to 2 local racks, 63 distributed I/O stations, and 3 distributed networks. It can handle up to 8000 distributed network discrete I/O points and 31744 remote system discrete I/O points. The module offers 768 kB RAM, 7168 kB expandable program space, and 8 MB expandable file storage via PCMCIA card, with data transfer rates of 10/100 Mbps. Supported communication protocols include Ethernet TCP/IP, Modbus, Modbus Plus, and USB, with optional modules for Ethernet, Modbus, Modbus Plus, Profibus DP, and Sy/Max. It operates with a maximum power dissipation of 11.28 watts (38.49 BTU/hour) and is compatible with Logix 5560 controllers, installed in ControlLogix chassis with an open cabinet rating.