ICP DAS tGW-718 is a tiny Modbus TCP/UDP to RTU/ASCII gateway featuring PoE (IEEE 802.3af) and a single RS-232/422/485 serial port. Supporting up to 32 simultaneous TCP master connections per serial port with a built-in read-cache for faster response, the tGW-718 bridges modern Ethernet networks with legacy serial Modbus devices in a compact DIN-rail form factor.
ICP DAS tGW-718 is a compact, cost-effective Modbus gateway designed to seamlessly bridge Modbus TCP/UDP networks with legacy Modbus RTU/ASCII serial devices. The unit supports both master and slave roles on Modbus TCP/UDP and Modbus RTU/ASCII, making it versatile for a wide range of industrial automation, building automation, and SCADA integration scenarios.
The tGW-718 accepts a single configurable RS-232/422/485 serial port, giving users flexibility to connect to different serial device types without requiring separate hardware models. Up to 32 simultaneous TCP master connections are supported per serial port, enabling multiple HMI, SCADA, or PLC masters to access the same serial slave devices concurrently without communication conflicts.
The built-in read-cache function stores previous Modbus requests and responses in a memory buffer. When multiple master controllers send the same request to the same RTU slave, the cached response is returned immediately — reducing serial port loading, accelerating TCP response time, and improving overall system stability.
Power is delivered via IEEE 802.3af PoE (Class 1) through a standard Cat5 Ethernet cable, eliminating the need for a separate power supply at the installation point. A DC jack input (+12–48 VDC) is also available as an alternative power source. Ultra-low power consumption of just 0.07 A at 24 VDC minimizes operating costs, especially in large-scale deployments.
A built-in web server provides an intuitive HTTP management interface for configuring IP settings (DHCP/Static), gateway/mask parameters, and serial port parameters — no additional software required. Dual watchdog protection (CPU watchdog + host watchdog) ensures continuous operation even in harsh environments: the CPU watchdog resets the firmware if it operates abnormally, while the host watchdog resets the CPU if communication with the host is lost within a predefined timeout period.
The tGW-718 supports ESD protection of ±4 kV, and the isolated variant (tGW-718i) provides 3,000 VDC signal isolation for enhanced noise immunity in demanding industrial environments. The wide operating temperature range of -25°C to +75°C ensures reliable performance across diverse industrial conditions.
