GT200-DP-MT Modbus TCP/PROFIBUS DP Gateway - Reliable Protocol Bridge

Our review of the GT200-DP-MT finds it to be a focused industrial gateway for teams that need a dependable bridge between Ethernet and PROFIBUS DP. The unit converts between Modbus TCP and PROFIBUS DP, acting as a PROFIBUS DP slave while supporting both client and server roles on Modbus TCP. For integrators migrating devices or linking a PROFIBUS DP master to a Modbus TCP network, the GT200-DP-MT delivers predictable protocol handling, solid galvanic isolation on the PROFIBUS interface, and a compact feature set designed for control-room and panel installations.

Key Features

• PROFIBUS DP slave: Automatically detects baud rates from 9600 bit/s to 12 Mbit/s so it integrates with a wide range of PROFIBUS masters without manual link configuration.
• Modbus TCP roles: Can operate as both Modbus TCP client and server, offering flexibility for different network topologies and master-slave assignments.
• Multi-server/client support: As a Modbus TCP client it can communicate with up to 36 Modbus TCP servers, simplifying polling of multiple devices with distinct IPs or identifiers.
• Concurrent connections: As a Modbus TCP server it accepts up to 36 client connections and supports the common function codes 03H, 04H, 06H and 10H for read/write operations.
• Data capacity: Supports up to 244 bytes of input and 244 bytes of output on both PROFIBUS and Modbus sides, sufficient for moderate I/O maps and tag sets.
• Rugged isolation and range: Provides 1 kV galvanic isolation on the PROFIBUS interface and an extended operating temperature range down to -40C and up to 70C for industrial environments.

Who It's For

The GT200-DP-MT is best for control engineers, system integrators, and industrial automation technicians who must connect legacy PROFIBUS DP systems to modern Ethernet-based Modbus TCP networks. Its support for both Modbus roles and multiple simultaneous connections makes it useful in migration projects, retrofit installations, and distributed I/O architectures.

It is not aimed at users needing large-scale data throughput or advanced protocol translation features beyond Modbus TCP and PROFIBUS DP mapping. Teams needing more complex protocol conversion, higher throughput, or expanded diagnostics should evaluate higher-end gateways or protocol converters.

Pros & Cons

Pros

• Supports both Modbus TCP client and server modes for flexible network roles.
• Automatic PROFIBUS baud detection simplifies integration with existing DP masters.
• 1 kV galvanic isolation on the PROFIBUS interface protects devices from ground loops and surges.
• Extended operating temperature range suits harsh industrial environments.

Cons

• Maximum data size of 244 bytes per side may limit very large tag maps or bulk data transfers.
• Modbus server function supports only 03H, 04H, 06H and 10H, which covers common needs but not every possible Modbus function.

Specifications

Our Verdict

The GT200-DP-MT is a practical, no-frills gateway for connecting PROFIBUS DP masters to Modbus TCP networks. Its combination of dual Modbus roles, multi-connection support, and robust PROFIBUS isolation makes it a good value for retrofit and integration projects where standard Modbus functions and moderate data capacity suffice. Choose it when protocol reliability and environmental tolerance matter more than advanced translation features.

Frequently Asked Questions

Can it act as both Modbus client and server at the same time?
No, the device supports Modbus TCP working as either a client (to poll up to 36 servers) or a server (accepting up to 36 client connections) depending on configuration.

What PROFIBUS speeds are supported?
It supports automatic baud detection across the PROFIBUS DP range from 9600 bit/s up to 12 Mbit/s.

Is the PROFIBUS interface protected against ground faults?
Yes, the PROFIBUS DP interface includes 1 kV galvanic isolation to reduce risks from ground loops and transient events.