UL924

a) our Struct12 supports a UPS power input at 44 to 52 volts to power the lights and DC loads in a house if the 120vac fails.   This is in addition to the redundant power supplies

b) the Struct12 detects the failure, and sends a command to all lights, for the max energy to be 5 or 10% of normal, assuring light and long battery life
c) the Struct12 sends a Group ON command to group 15 - any light in this group, will be turned on to 10% - overriding the switch in the room.  This insures that there is light even if the wall switch cannot be found

a) our AL-ATS-8-7D PoE switch detects the failure of the 120vac mains and changes the PoE outputs from 802.3at to 802.3af
b) our AL-AT-TW1 PoE LED driver switches from full power mode to 5% mode, reducing the battery run time
c) this 802.3af mode overrides any user switch - forcing all lights to be on at 5%
c) by default - all outputs switch to 802.3af.   A knowledgeable admin, can assign rules to each port to be off instead of 802.3af, further extending battery run time.