Board-Mount Screw Terminal with a Surface-Mount Twist
The TE Connectivity Buchanan Termi-Blok 2383941-8 is an 8-position, single-level PCB-mount terminal block that breaks the usual through-hole mold — it lands on surface-mount pads instead of plated holes. The 0.150" (3.81mm) pitch gives enough room between positions for the M2 screw and the rising cage clamp mechanism, so the board layout sees a standard 3.81mm grid. Rated 7 A at 300 V, it handles control and sensor-level power, not main bus feeds. The black polyamide housing carries a board guide feature to align the part during reflow placement.
Wiring It — Torque, Wire Range, and the Rising Cage
Wire termination is a screw-actuated rising cage clamp — the screw lifts a nickel-plated copper alloy plate that traps the conductor against the top of the tunnel. The M2 screw takes a specified torque of 0.5-0.6 Nm (4.4-5.3 Lb-In), which means you need a torque driver on this assembly step; under-torque leaves the wire loose, over-torque strips the nylon threads. Accepts 18-28 AWG solid or stranded wire — 18 AWG is the practical limit for the cage opening.
SMT Reality Check — Pads Take the Torque
Surface-mount termination on a screw-clamp block is a mechanical compromise — the solder joints alone must hold the screw torque during field wiring. The board guide feature helps alignment during reflow, but the PCB pad design needs to account for the 0.5-0.6 Nm torque reaction.