{"product_id":"allen-bradley-1775-s4b-plc-3-i-o-scanner-message-handling-module","title":"Allen-Bradley 1775-S4B PLC-3 I\/O Scanner Message Handling Module","description":"\u003cp\u003eConfigured for high-capacity I\/O scanning, message buffer processing, and serial interface translation in PLC-3 rack structures, the \u003cstrong\u003eAllen-Bradley 1775-S4B\u003c\/strong\u003e (\u003cstrong\u003e1775-S4B\u003c\/strong\u003e I\/O Scanner Message Handling Module) provides direct physical\/electrical execution.\u003c\/p\u003e\n\u003ch3\u003eArchitectural Designation \u0026amp; System Integration\u003c\/h3\u003e\n\u003cp\u003eThe catalog identifier \u003cstrong\u003e1775-S4B\u003c\/strong\u003e specifies an I\/O scanner and message handling module designed for PLC-3 control architectures. The module establishes 4 dedicated remote I\/O communication channels paired with 1 serial RS-232-C port, handling up to 2048 discrete inputs and 2048 discrete outputs with an internal 16-word message buffer.\u003c\/p\u003e\n\u003ch3\u003eOperational Parameters \u0026amp; Ratings\u003c\/h3\u003e\n\u003cfigure\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003e1775-S4B\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eUSA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e2.3 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShipping Dimensions\u003c\/td\u003e\n\u003ctd\u003e5.1 x 27.9 x 30.5 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e0 to +60 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e50 W (peak)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackplane Current Draw\u003c\/td\u003e\n\u003ctd\u003e2.7 A at 5 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSystem Capacity\u003c\/td\u003e\n\u003ctd\u003e2048 Inputs and 2048 Outputs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Ports\u003c\/td\u003e\n\u003ctd\u003e4 I\/O Channels, 1 RS-232-C Serial Port\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eI\/O Transmission Rate\u003c\/td\u003e\n\u003ctd\u003e57.6 kbaud or 115.2 kbaud\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRS-232-C Baud Rate\u003c\/td\u003e\n\u003ctd\u003e110 to 19.2 kbaud\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eI\/O Scan Time\u003c\/td\u003e\n\u003ctd\u003e5.5 to 6.5 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMessage Buffer Size\u003c\/td\u003e\n\u003ctd\u003e16 words\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Rack Address\u003c\/td\u003e\n\u003ctd\u003e7 (Octal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Supply Voltage\u003c\/td\u003e\n\u003ctd\u003e115\/230 VAC (+\/-15%)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtection Fusing\u003c\/td\u003e\n\u003ctd\u003e2 A (115 V), 1 A (230 V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGalvanic Isolation\u003c\/td\u003e\n\u003ctd\u003e1500 VAC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTariff Code\u003c\/td\u003e\n\u003ctd\u003e8537101190\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eDeterministic Communications \u0026amp; Network Integration\u003c\/h3\u003e\n\u003cp\u003eThe module optimizes backplane bus communication velocity across the rack assembly, providing synchronized message routing to central processors. Integrated diagnostic monitoring verifies firmware flash compatibility across connected nodes, ensuring low-latency frame parsing and predictable execution when managing complex I\/O density scaling profiles.\u003c\/p\u003e\n\u003ch3\u003ePackage Component Checklist\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1 x Allen-Bradley 1775-S4B I\/O Scanner Message Handling Module\u003c\/li\u003e\n\u003cli\u003e1 x Protective Static Shield Packaging Envelope\u003c\/li\u003e\n\u003cli\u003e1 x System Installation and Wiring Guide\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eField Cabinet Installation Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eChassis Alignment\u003c\/strong\u003e: Insert the module firmly into its designated chassis slot with power isolated to protect internal backplane connectors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSerial Interface Wiring\u003c\/strong\u003e: Connect RS-232-C serial cables using shielded twisted-pair wiring with low capacitance ratings to maintain baud rate integrity.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemote I\/O Line Routing\u003c\/strong\u003e: Run 4 independent remote I\/O communication channels in isolated conduits separate from high-voltage AC power lines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEarthing and Shielding\u003c\/strong\u003e: Secure all cable shields to the main panel earthing bar at a single point to prevent ground loop currents across communication lines.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the backplane current draw for the 1775-S4B module?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe module draws 2.7 A from the 5 VDC chassis backplane supply rail during normal execution.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat maximum I\/O count can be managed by the 1775-S4B?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe module handles a maximum capacity of 2048 discrete inputs and 2048 discrete outputs across its channels.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat baud rates are supported on the remote I\/O channels?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe 4 remote I\/O communication ports support selectable transfer rates of 57.6 kbaud or 115.2 kbaud.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the typical I\/O scan response time for this module?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe hardware completes an internal I\/O scan cycle within a timing window of 5.5 ms to 6.5 ms.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat size is the integrated message buffer?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe module incorporates an internal hardware buffer capacity of 16 words for serial message handling.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat fuse protection is required for line supply power?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe internal power circuit uses a 2 A fuse for 115 V operation or a 1 A fuse for 230 V operation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the module support live removal from the rack backplane?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo, backplane power must be completely isolated prior to inserting or extracting the module.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWhat isolation rating is provided between power and logic circuits?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe integrated power section provides internal galvanic isolation rated up to 1500 VAC.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":46066446467245,"sku":"1775-S4B","price":88.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0733\/1613\/9181\/files\/1775-S4B-0.jpg?v=1786072727","url":"https:\/\/www.maxwellplc.com\/products\/allen-bradley-1775-s4b-plc-3-i-o-scanner-message-handling-module","provider":"Maxwell PLC Ltd","version":"1.0","type":"link"}