The SIP-based Algo 8028 Voice over IP Intercom is ideally suited for applications involving the upgrade/retrofit of an existing analog intercom to IP where only twisted pair is available. The separate controller ensures that both the network connection and door opening control relay of the 8028 cannot be tampered with from the public-facing intercom. The 8028 door control relay can connect to any type of door release, gate activation system or access control panel. The intercom includes a 24 V 0.3 A power source for low power 24 V door strikes (customer provided). Additionally, there are low current programmable inputs and outputs at both control unit and intercom station for door sensing, door unlock switch, door unlock override, auxiliary call buttons, or telephone status such as ringing or in-use. FCC & CISPR22 Class B approval for residential use. See manufacturer's website for specifications, new features, and any firmware updates. A basic understanding of computer networking and Voice over IP experience is required.