The Acu‑Rite ENC 125T (part 557870‑38) is a precision glass linear encoder with 10 µm resolution and up to 38″ travel, typically mounted on heavy‑load machines or motion control systems. Common failure points for this class of encoders include cable breakage or fraying in the braided shield, contamination of the optical sensor surface, misalignment of the scale relative to the read head, and loss of proper grounding leading to signal noise. First‑check diagnostics should verify power and signal integrity on the encoder’s 4‑wire interface, inspect the cable for physical damage or kinks, clean the glass surface with a lint‑free cloth and appropriate solvent, and confirm that the mounting bracket is level and free from vibration or mechanical stress.[oss-gpt-20b]