The 1747-BSN is a Backup Scanner Module in communication with 1746 backplane SLC processor. This communication module is compatible with SLC 5/02, 5/03, 5/04, and 5/05 processors. 1747BSN scans I/O and passes retentive data between backup scanner modules to provide backup when a fault may occur. Communication port protocol for 1747BSN is the universal remote I/O scanner, high-speed serial link, and local serical link. Backplane current load for this module is 800mA at 5 V DC.