2 or 4 wire smoke detector question.
Do any 4 wire units have a built in battery backup as do 110 VAC units?
read more and respond »Posted 5 years ago by BoyntonStu in CCTV, Alarms and other Physical Security
Do any 4 wire units have a built in battery backup as do 110 VAC units?
read more and respond »Posted 5 years ago by BoyntonStu in CCTV, Alarms and other Physical Security