When triggered, all smoke detectors in your home alarm concurrently. Challenging-wired detectors are normally on and when the facility goes out, the battery backup kicks in.??? ?? ?????? ?????? ???????? ????? ???? ??? ?????? ?????? ???? ???????,  ????? ?????? ??? ?????? ??????? ??? ???? ?????? ????? ??? ?????????????? ????? ??? ?????: ?????????