Outdoor wireless siren EWS2 is external power supplied siren with integrated wireless module EW1. This wireless module EW1 connects to ELDES wireless security systems and managing EWS2 siren to work with the system. Users have to bind it to the central device of security system (by sending a corresponding command via SMS message or using software „ELDES Configuration Tool“) and configure input zones and outputs. Connected devices are recognized as central security system devices and can be controlled via system phone number. The siren has integrated battery and in case of power supply failure, it starts alarming. When the system is violated, the siren alarms for one minute. EW1 module also has one unused zone and one unused output. They can be used to connect variuos additional devices such as motion sensors, smoke detectors and etc (see wireless expansion module EW1 manual).