What does the "RE OFF" indication mean?
The RE OFF indicator will be displayed if the RED ENABLE input is not active. This indicates that Red Fail Monitoring, Dual Indication Monitoring, and Clearance Monitoring are disabled
The monitor is letting you know that it is not monitoring Red Fail Monitoring, Dual Indication Monitoring, and Clearance Monitoring.
This indication will also illuminate in a TS1 cabinet if you turn on the flash switch on the police panel. So check the police panel to make sure that it is not in the flash state.
The SSM switches on the SSM-LE series Signal Monitor are labeled "1" to "12" ("6") corresponding to channels 1 through 12 (6), respectively. Positioning a switch in the ON position (to the right) enables a channel for Dual Indication AND Clearance Monitoring.