What the SS-5-F-2-T is on the BOM
The SS-5-F-2-T is an Omron subminiature limit switch from the Limit Switches line, ordered under that exact code for position and end-of-travel feedback on panels and motion hardware. Its contact arrangement is single-pole, single-throw, normally-closed (SPST-NC), so the circuit is closed in the resting (un-actuated) state and opens when the actuator reaches the trip point — the typical wiring for a stop-limit or guard-interlock return-to-safe check.
Switch configuration in plain terms
SPST-NC means a single mechanical contact, one direction of state change, biased closed: pick this when the machine logic expects a proven signal that proves itself by going open on actuation, instead of a NO contact that has to prove it can close. On the panel side, a normally-closed contact pairs naturally with a safety-style input that looks for the open transition as the trip event — useful for end-of-travel limits on cylinder rods, drawer or guard position sensors, and similar mechanical stops where the un-tripped state must read healthy.