PT Series Earth (Ground) Modular Terminal Blocks A professional range of PT series earth DIN Rail terminal blocks from Phoenix Contact. These push in connection terminal blocks are characterised by the system features of the CLIPLINE complete system and by easy tool-free wiring of conductors with ferrules or solid conductors. The PT series terminal blocks are a compact design and front connection enabling a wide range of cable size wiring in confined space. All terminal blocks provide an addition test connection and are highly reliable and excellent quality.