Introduction

In critical industrial processes, uninterrupted communication between control systems and field devices is paramount. A failure in a serial communication link, whether due to master hardware failure or cable damage, can lead to costly downtime and operational disruption. The SAM 201I Isolated Serial Redundancy Switch is a specialized hardware solution engineered to address this vulnerability by providing robust, automatic failover for serial port communications, ensuring operational continuity.

The core function of the SAM 201I is to enable redundancy for protocol-independent RS232 serial ports. The device features three fully isolated serial ports that can be configured to manage communication traffic automatically. During power-on, the device connects the slave port to whichever master first sends a query. From that point, it continuously monitors the active communication line, and if it senses a 'No Communication' state, it seamlessly transfers control to the secondary, or backup, line. This ensures that the connection between master controllers and slave devices remains active even if the primary path fails.