Description

Features

• Automatically transfers control to standby PLC upon loss of I/O scan or “heartbeat” pulse from the active PLC
• Switches both remote I/O and serially attached operator interface devices
• Enables PLC logic to monitor status and control switchover, if desired.
• Allows optional manual switchover capability
• Uses high-reliability relays to directly connect the active PLC and remote I/O without intervening
• electronics.
• Defaults to a user-defined switched position on power loss or hardware failure
• Provides LEDs to visually indicate status of control
• Transfers up to 4096 words of critical data between active and standby PLCs every scan