Gateways & Modems

Gateways & Modems

Gateways and modems are connectivity components that expose field device and network data to configuration and monitoring tools. They provide a managed access layer between plant networks and instrument communication standards, so diagnostics and parameters can be reached without interrupting the measurement chain. In mixed-protocol environments, they function as a controlled entry point into device data.

A modem is primarily a protocol converter for point‑to‑point access. It links a computer or handheld to a device interface (for example, HART-to-USB or fieldbus-to-Bluetooth conversions), enabling configuration software to communicate directly with an instrument. This is well suited to commissioning, device replacement, or targeted troubleshooting at a specific loop. In practice, this supports a laptop-based workflow for detailed parameter checks, verification steps, and diagnostics at the device.

A gateway provides parallel access into a running network. By connecting a computer’s Ethernet side to a fieldbus segment, multiple devices can be accessed through a single entry point. Gateways often add value beyond conversion by supporting network and device status monitoring and presenting diagnostics through common tools such as a standard web browser. In addition to protocol conversion, gateways can support device configuration environments (e.g., FieldCare) as a parallel network access point and enable remote monitoring and maintenance via a web browser.

Benefits show up as faster commissioning, fewer site trips, and earlier identification of developing device or network issues. Standardized device status indications (including approaches aligned with NAMUR NE 107) improve triage and help focus effort where it reduces risk. Because these components bridge network domains, they also support repeatable workflows when access paths, credentials, and segmentation are clearly defined. When used as permanent infrastructure, they reduce the need for temporary hook-ups and help keep diagnostic access consistent across the site.

Typical applications include adding visibility to PROFIBUS and HART installations, enabling remote status monitoring for skids or tank farms, and providing quick access during turnarounds without repeatedly opening cabinets or instrument enclosures. Modems serve as portable interfaces for on-demand work, while gateways remain installed for continuous access and monitoring.

Forberg Smith, an exclusive authorized representative of sales and service for Endress+Hauser.