Fax Line Wiring Diagram. The phone line usually comes in by your electrical panel. In that case the blue pairs are for the first line and use the orange pairs for the second line.
In most residential phone wiring the cable contains four individual wires. Most cable nowadays is UTP unshielded twisted pair. There may be instances where you may need to connect to or transpose from the old quad cable.
Not used WhiteGreen.
The kind of wire shown above has recently become obsolete. Jan 24 18 0209 PM. They are used in pairs for each phone line you have. Switched Outlet Wiring Diagram.