W&T 58631 Com-Server RS-232/485 to TCP/IP Replacement

Product Overview

W&T 58631 Com-Server RS-232/485 to TCP/IP Replacement: Seamless Migration from Legacy Serial Systems

The Wiesemann & Theis (W&T) 58631 Com-Server is a proven industrial-grade Serial-to-Ethernet gateway that converts RS-232 and RS-485 serial interfaces to TCP/IP Ethernet communication. As legacy serial-based control architectures reach end-of-life or become increasingly difficult to maintain, the W&T 58631 provides a direct, low-disruption upgrade path for engineers managing aging SCADA systems, DCS networks, PLC communication backbones, and distributed I/O installations.

This product page is designed to support procurement engineers, system integrators, and plant maintenance teams who need a verified, in-stock replacement for the W&T 58631 — with full compatibility documentation, retrofit guidance, and a 12-month warranty assurance.

Compatibility Comparison Table

Seamless Upgrade Solutions

Migrating from a legacy serial communication architecture to a modern TCP/IP-based network involves more than swapping a single device. A successful retrofit of the W&T 58631 typically requires coordinating several interconnected components across the control cabinet and field network.

In most installations, the 58631 interfaces directly with PLCs or DCS controllers that use RS-485 Modbus RTU — such as Siemens S7-300 CP modules, Schneider Electric Modicon Quantum communication adapters, or ABB AC500 serial communication cards. When these controllers are upgraded or their serial ports are consolidated onto Ethernet backbones, the 58631 acts as the transparent bridge, preserving existing Modbus RTU polling cycles without requiring PLC program changes.

On the field side, the 58631 commonly connects to RS-485 multi-drop networks serving remote I/O modules, intelligent field devices, or legacy HMI panels. Devices such as Siemens OP/TP series operator panels, Weintek MT series HMIs, or Advantech ADAM-4000 series remote I/O modules can continue operating on their native RS-485 protocols while the 58631 tunnels the data transparently over Ethernet to the SCADA host or DCS server.

For installations where multiple serial channels must be migrated simultaneously, the W&T Com-Server family includes multi-port variants that share the same configuration interface and firmware architecture as the 58631, allowing a standardized migration approach across the plant. Complementary components such as W&T 57631 (4-port Com-Server) or W&T 58537 (Com-Server Office) may be evaluated for multi-channel consolidation projects.

Power supply compatibility is a key consideration during retrofit. The 58631 operates on 24 VDC, which aligns with standard control cabinet power rails supplied by Phoenix Contact QUINT or Siemens SITOP power supply units. No additional power conversion is required in most DIN-rail cabinet environments.

For installations requiring signal isolation between the RS-485 bus and the Ethernet segment — particularly in environments with high electrical noise from variable frequency drives (VFDs) or motor starters — inline RS-485 signal isolators or surge protectors (such as Phoenix Contact TRABTECH or Weidmüller DEK series) are recommended as part of the retrofit bill of materials.

Programming cable requirements are minimal: the 58631 is configured entirely via web browser over Ethernet, eliminating the need for proprietary programming cables or software licenses. This significantly reduces commissioning time compared to older serial-configured gateways.

Retrofit Guidance FAQ

Q: Can the W&T 58631 replace my existing serial gateway without changing PLC programs?
A: Yes. The 58631 operates as a transparent serial-to-TCP/IP tunnel. Existing Modbus RTU or ASCII polling programs running on the PLC or SCADA host do not require modification, provided the host software supports Modbus TCP or RFC 2217 virtual COM port drivers.

Q: What wiring changes are required during installation?
A: The RS-232 or RS-485 field wiring connects directly to the 58631’s DB9 connector or terminal block — matching the pinout of most legacy Com-Server variants. The only new wiring required is the RJ45 Ethernet cable to the plant network switch. 24 VDC power connects via the existing cabinet power rail.

Q: Is the 58631 compatible with Modbus TCP SCADA systems?
A: Yes. The 58631 supports Modbus TCP gateway mode, allowing Modbus TCP masters (WinCC, iFIX, Ignition, InTouch) to poll RS-485 Modbus RTU field devices through the gateway without protocol conversion software on the SCADA server.

Q: How much DIN rail space does the 58631 require?
A: The 58631 occupies approximately 45 mm of DIN rail width, making it suitable for installation in standard 19-inch control cabinets or compact junction boxes alongside terminal blocks and power supplies.

Q: Can the 58631 be configured remotely after installation?
A: Yes. All configuration is performed via the built-in web interface accessible from any browser on the plant network. SNMP management and Telnet access are also supported for integration with network management systems.

Q: What happens if the Ethernet network fails — does the serial device still operate?
A: The serial port remains active and the field device continues to respond to serial polling. The gateway buffers data and re-establishes the TCP connection automatically when the network recovers, minimizing data loss during network interruptions.

Warranty Assurance

Every W&T 58631 Com-Server unit shipped by TOPNLMS is covered by a 12-month warranty from the date of delivery. Prior to shipment, each unit undergoes functional verification including power-on testing, serial port loopback checks, Ethernet connectivity confirmation, and web interface accessibility validation.

In the event of a confirmed hardware defect within the warranty period, TOPNLMS provides direct replacement support with priority processing. Our technical team is available to assist with pre-installation compatibility verification, configuration guidance, and post-installation commissioning questions.

Units are shipped from our Xiamen warehouse with full export documentation, commercial invoice, and packing list. Standard lead time for in-stock units is 3–7 business days for international destinations. Express shipping options are available for urgent plant maintenance requirements.

For procurement teams requiring batch quantities, factory test reports, or third-party inspection certificates, please contact our sales team directly to arrange documentation prior to shipment.

We understand that unplanned downtime in industrial environments carries significant operational cost. Our inventory management and rapid dispatch process is designed to minimize the time between your purchase order and the arrival of a tested, ready-to-install replacement unit at your facility.