If GS1100 can’t read any tag (SCAN LED [1 blink] -> 3 short beeps -> B/L LED [1 blink] -> SCAN LED [3 blinks every 2 seconds] when you press and hold the SCAN button for 10 seconds)

It indicates that RTC (Real Time Clock) error of GS1100 occurs. Use “Set Time” or “Sync. Time” function of the software GuardScan Monitor to set date and time for GS1100. If that doesn’t work, send GS1100 to GIGA-TMS for further inspection.