Product Details:

MODICON ASB984100, full part number AS-B984-100, is a high speed logic solver and S908 remote I/O interface module for Modicon 800 series automation platform. It undertakes fast discrete logic calculation and serves as the communication gateway between host PLC and distributed remote I/O racks over S908 coaxial RIO network. This unit carries integrated power supply for local rack I/O and two built-in ASCII serial ports for connecting third-party intelligent devices, printers and operator terminals. It features ultra-fast signal response for time-critical interlock, high-speed counting and synchronous logic tasks which cannot be handled efficiently by the main CPU scan cycle. It adopts standard rack mounting and inserts directly into Modicon 800 backplane, with dedicated LED indicators for network status, power and logic operation alarm. Industrial-grade EMC and surge suppression circuits protect internal logic from heavy electrical noise on factory floors. As an obsolete original spare part, it is used for maintenance and retrofit of legacy Modicon distributed process control systems. Direct replacement keeps the existing coaxial RIO wiring, serial peripheral layout and high-speed interlock scheme unchanged, eliminating redesign of critical fast logic loops and reducing production downtime.

Basic Parameters

Product type: high speed logic solver with S908 RIO interface

Communication: S908 HDLC coaxial RIO, dual ASCII serial ports

Supply: 5 Vdc backplane, auxiliary power for local I/O

Input response: down to 100 microseconds without filter

Installation: rack mount for Modicon 800 backplane

Operating temperature: 0°C ~ +60°C

Protection grade: IP20

Supported Functions

High speed discrete logic execution

S908 RIO network data exchange

ASCII serial data transmission and reception

Fast interlock and trigger processing

Remote rack power feed

Backplane data exchange with host CPU

Core Functions

Real-time high-speed logic computation

Onboard multi-status LED indication

Coaxial bus transient surge suppression

Serial port frame parsing and forwarding

Fault flag capture for communication and logic error

Diagnostic information output for on-site troubleshooting

Hardware Specifications & Environmental Features

Built-in bus noise filtering and surge suppression circuit

Storage temperature: -25°C ~ +70°C

Relative humidity: 5% to 95% non-condensing

Status: Obsolete original part, available for spare replacement

Industry Applications: Applied in legacy furnace safety interlock, old high-speed packaging synchronization, petrochemical emergency shutdown auxiliary logic and large conveyor fast interlock automation racks.

Note: Confirm S908 single cable configuration, backplane compatibility and serial wiring definition before ordering.

This is from our current stock.

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