25Expanding the SystemUnits required to be installedAdding a door station:Door station (up to 2 units including your original unit)Operating the door opener:Door opener (up to 2 units)* 2Connecting to a door opener allows you to open the door using the{DOOR KEY} on the main monitor station (page 11).Using with Panasonic PBX:Connecting to a PBX allows you to answer calls from the door station using additional machines(extensions).Please use only a Panasonic PBX (page 3).Note:● If you answer a call from the door station with a PBX extension, thecamera image taken by the door station will be displayed at the mainmonitor station. will appear in the top of the display indicatingthat a PBX extension is on the call (see C on page 7). Whileis displayed, you cannot answer the call using the main monitorstation. The display will turn off when the conversation between thedoor station and the PBX extension ends, or if the call duration time islonger than 3 minutes.● If you answer a call from the door station with the main monitor station,the call will continue to ring at the extension for about 15 to 30 seconds.Even if an extension user wants to answer the call while the call is ringing,the extension user cannot participate in the call.When using two door stations(excluding an optional lobby station, page 3):From the PBX extension, you can call up the only one door station thathas received the last incoming call or has talked with.VL-V566BXorVL-GC005BX* 2You can also connect anoptional lobby station forapartment complexes (page 3).Door openerPBXTerminal box