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The Yokogawa ALF111‑S51 FOUNDATION Fieldbus Communication Module is an industrial‑grade communication interface designed to support FOUNDATION Fieldbus (H1) networks — a digital, two‑way, multidrop communications system widely used in process automation. This module enables efficient, real‑time data exchange between field devices (such as transmitters, actuators, and smart sensors) and controllers, enhancing system integration, monitoring, and control in distributed control systems (DCS) and process platforms.
Key Features:
FOUNDATION Fieldbus support: Provides reliable Fieldbus communication (H1 standard) for distributed automation networks
Multi‑segment connectivity: Allows connection of multiple Fieldbus segments and field devices for scalable system design
Link Active Scheduler (LAS) & timing functions: Coordinates communication and scheduling on the Fieldbus network for stable data flow
Redundancy‑ready: Supports redundant configurations to improve system availability and uptime
Rugged industrial build: Designed to operate reliably in harsh industrial environments with secure terminals and robust construction
Seamless integration: Compatible with Yokogawa field control units and distributed automation architectures
Specifications:
Model: ALF111‑S51
Type: FOUNDATION Fieldbus Communication Module
Fieldbus Protocol: FOUNDATION Fieldbus (H1)
Transmission Speed: Standard Fieldbus rate (31.25 kbps)
Ports: Multiple Fieldbus segment connections
Communication Functions: Link Active Scheduler, Clock Master, device scheduling
Redundancy: Dual‑module redundancy support
Current Consumption: Industrial‑typical usage
Compatibility: Designed for integration with Yokogawa automation systems, controllers, and field networks
Reliable, precise, and engineered for industrial automation, the Yokogawa ALF111‑S51 FOUNDATION Fieldbus Communication Module ensures coordinated communication and robust data exchange across Fieldbus segments — enhancing system performance, scalability, and uptime in complex process control environments.
Returns Policy
You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Shipping
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