Greyline Cincinnati Electrosystems Operator Panel-128-D Operator Panel

The Greyline Cincinnati Electrosystems Operator Panel-128-D is a compact vacuum-fluorescent operator interface from the Greyline 2000-series family, designed to serve as the on‑machine human–machine interface for legacy Cincinnati Dynacomp controls. It uses a green vacuum fluorescent display with 20 characters per line and supports 2-line (2124) or 4-line (2125) configurations, with an optional 128K memory to store messages or programs. The enclosure measures about 6.85 inches wide, 7.70 inches high, and 3.67 inches deep and weighs roughly 2 lb, and it offers Port A for internal fixed parameters, Port B for PLC communications (RS‑232, RS‑422, RS‑485 or current loop) at common baud rates up to 19.2K, plus an auxiliary Port X for additional serial connections. Mounting hardware and panel-sealing options provide indoor use with Type 4X protection, operating temperature 0–50 C, storage -20 to 60 C, humidity 10–95% non-condensing, and UL/CUL approvals. In catalog ecosystems, the 128‑D designation is commonly paired with 128K memory options and four-line displays, reflecting its status as a legacy operator interface that many suppliers list as discontinued by the manufacturer.