{"product_id":"yokogawa-alf111-s01-foundation-fieldbus-communication-module","title":"Yokogawa ALF111-S01 FOUNDATION Fieldbus Communication Module","description":"\u003cp\u003eThe \u003cstrong\u003eYokogawa ALF111-S01\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eALF111\u003c\/strong\u003e FOUNDATION Fieldbus Communication Module, operates as a dedicated hardware component for Link Active Scheduler (LAS) management and H1 fieldbus segment distribution within distributed control system (DCS) platforms.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cp\u003eThe ALF111 series utilizes explicit engineering suffixes to define hardware builds and hardware style revisions. Below is the technical breakdown for the \u003cstrong\u003eALF111-S01\u003c\/strong\u003e configuration:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eALF111\u003c\/strong\u003e: Core base model designator for the FOUNDATION Fieldbus H1 communication module.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e-S\u003c\/strong\u003e: Standard type construction baseline for standard industrial enclosure installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e0\u003c\/strong\u003e: Phase indicator slot mapping designator.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1\u003c\/strong\u003e: Style code indicating the physical hardware design revision or updated sub-component generation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\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\u003eALF111-S01\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eYokogawa\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eJapan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e150 g (0.33 lbs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e88 mm (W) x 58 mm (H) x 23 mm (D)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003eStandard industrial cabinet environmental parameters apply\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Supply Voltage\u003c\/td\u003e\n\u003ctd\u003e24 VDC plus\/minus 10 percent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e4.5 W maximum rated draw\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eFieldbus Communication Modules\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePhysical Interface\u003c\/td\u003e\n\u003ctd\u003eFOUNDATION Fieldbus H1 segment\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Speed\u003c\/td\u003e\n\u003ctd\u003e31.25 kbit\/s fixed transmission rate\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSegment Capacity\u003c\/td\u003e\n\u003ctd\u003e1 primary H1 fieldbus segment loop\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDevice Capacity\u003c\/td\u003e\n\u003ctd\u003eMaximum 32 fieldbus devices per segment loop\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRedundancy Support\u003c\/td\u003e\n\u003ctd\u003eDual-redundant configuration pairing compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eProcess Control System Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFOUNDATION Fieldbus \/ Profibus PA Connectivity\u003c\/strong\u003e Operating as a Link Active Scheduler (LAS) master node, the module maintains strict deterministic control over the 31.25 kbit\/s H1 segment loop. It governs macrocycle execution timings, issues token passes to slave instruments, and transfers periodic process variables directly into the central DCS database for regulatory control loop synchronization.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeterministic Processor Offloading and Redundancy Pairing\u003c\/strong\u003e The module manages synchronous scheduled communications and asynchronous messaging internally, ensuring network traffic routines do not introduce execution jitter to the main controller processor. Dual-redundant pairing options support installing two ALF111 units in the same node slot layer to manage automatic bump-less transfer of the LAS roll during an active hardware fault.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: What are the consequences if a module running as the active Link Active Scheduler (LAS) fails on the H1 loop?\u003c\/p\u003e\n\u003cp\u003eA: If the primary ALF111-S01 fails in a non-redundant layout, a configured backup LAS device located directly on the field network segment detects the loss of the scheduling token and automatically assumes control of the macrocycle execution timing to prevent loss of process data.\u003c\/p\u003e\n\u003cp\u003eQ: Can the ALF111-S01 directly power the 32 fieldbus transmitters connected to its H1 segment loop?\u003c\/p\u003e\n\u003cp\u003eA: No. The communication module does not inject operating power into the signal lines. An external, dedicated fieldbus power supply paired with an impedance-matching fieldbus power conditioner must be installed on the H1 network segment to drive connected transmitters and valves.\u003c\/p\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":47621293834430,"sku":"ALF111-S01","price":3000.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/screenshot_2026-06-09_17-36-44_ffe79103-4c9e-46a2-aff6-e2a5f8f0f99c.png?v=1781164403","url":"https:\/\/www.autooiltech.com\/products\/yokogawa-alf111-s01-foundation-fieldbus-communication-module","provider":"AutoOilTech Limited","version":"1.0","type":"link"}