Title: Hardware Installation Guide.pdf
K4Relay K1: ON = Energized (Reader 2 Aux output 1)Note:If this input is defined, every three seconds the LED is pulsed to its opposite state for 0.1 seconds, otherwise, the LED is off.When the controller is reading the database, LEDs 1-4 will simultaneously flash once every two seconds. When the controller is saving the card database, LEDs 1-4 will simultaneously flash in a progressively faster pattern until completion. The final pattern may be so fast that it is hard to distinguish from constant on. Saving large databases can take several seconds.The LED patterns used for Heartbeat, Host communication, and downstream communication will be suspended during the save/restore and will return to normal once the save/restore is complete.38.2Replace Memory Backup BatteryThe event log buffer and the real time clock are backed up by a 3V lithium battery. Without power being applied to the LNL-4420, the battery will retain events and transactions for 3 months.