Product Details：

Honeywell 51195096200 (51195096-200, PLCI I/O Board) is a rack plug-in hybrid I/O interface board for Honeywell TDC3000 legacy DCS system,its main purpose is stable bidirectional signal conversion and data exchange between the backplane bus and on-site process instruments. This board is the upgraded variant of 51195096100,optimized for higher channel density and stronger noise suppression in heavy industrial interference environments. It receives 4-20mA analog current signals from pressure,temperature,flow and level transmitters,and dry contact digital signals from limit switches,interlock switches and status feedback devices. After filtering,amplification and A/D conversion,the collected field signals are converted into digital data and transmitted to the TDC3000 processor through the rack backplane bus for closed-loop control calculation,alarm judgment and trend recording on the operator station. Meanwhile,it receives control commands issued by the controller,converts digital instructions into analog output signals or relay contact switching actions to drive field regulating valves and solenoid valves. Each channel adopts independent isolation and transient voltage suppression circuit,which can effectively eliminate common-mode noise and ground loop drift on long instrument cables. It supports channel-level fault detection,identifying open circuit,short circuit and signal over-range conditions,recording timestamped fault logs and uploading alarm messages to the LCN network for maintenance engineers to locate abnormal channels quickly. It is an obsolete original spare board,mainly used for maintenance and reconstruction of old TDC3000 control racks in petrochemical,chemical and power plants. It supports hot swap under authorized lockout-tagout maintenance procedures to minimize shutdown risk for continuous production loops.

Key specifications：Standard TDC3000 rack plug-in board,hybrid analog and digital I/O channels,4-20mA and dry contact signal support. Operating temperature range is 0°C to +60°C. It supports wire break,over-range,short circuit and channel communication fault diagnosis. The PCB is conformal coated for dust and moisture resistance,built-in EMC filter circuits reduce surge interference inside the cabinet. Front panel numbered terminal blocks and LED indicators display channel signal status and fault warning for quick on-site inspection.

This PLCI I/O board is widely deployed in petrochemical,chemical,power generation and water treatment plants for legacy TDC3000 DCS maintenance and renovation projects. It cooperates with Honeywell LCN adapter board,clock source board and operator station hardware to build a complete distributed control network. As a core unit for PLCI I/O board and signal interface,it is the upgraded field signal access hardware for TDC3000 I/O subrack. Clearly numbered channel terminals simplify field instrument wiring,loop calibration and periodic signal accuracy verification work for control engineers.