2 Way and Intermediate Switching Joint Box Method Wiring Diagram Connections Explained Student training aid for the connections required to wire two way and intermediate switching joint box method. Video explains via a wiring diagram the connection required within the joint box, two way switches and intermediate switch. The circuit is wired in twin and cpc cables (twin and earth cable) and 3 core and cpc cable. Videos are training aids for City and Guilds (C and G) and EAL courses Level 1, 2, 3