So what is the job of the sounders?

The internal and external sounders are buzzers which, when alerted by the main panel that there is an intrusion, make a very loud noise in order to deter the intruder from proceeding undisturbed further inside the house. The loud noise can be heard from neighbours’ houses so it catches the attention of the neighbourhood. However, the sounder will not be able to protect your premises on its own, as it needs the main panel to give it the signal to go on. Frequently, external sounders have running lights to enhance visibility and are placed in very visible areas to act as deterrents.