ICP DAS tGW-732 is a tiny Modbus TCP/UDP to RTU/ASCII gateway featuring PoE (IEEE 802.3af) and three RS-232 serial ports. Supporting up to 32 simultaneous TCP master connections per serial port with built-in read-cache for faster response, the tGW-732 enables multiple HMI/SCADA masters to access serial Modbus slave devices simultaneously through a compact DIN-rail form factor.
ICP DAS tGW-732 is a compact, cost-effective Modbus gateway that bridges Modbus TCP/UDP networks with legacy Modbus RTU/ASCII serial devices across three independent RS-232 serial ports. Supporting both master and slave roles on Modbus TCP/UDP and Modbus RTU/ASCII, the tGW-732 is well-suited for applications requiring simultaneous communication with multiple independent serial device groups — such as multi-zone building automation systems, factory floor SCADA networks, or distributed remote terminal unit (RTU) deployments.
Each of the three RS-232 serial ports operates independently, each mapped to a dedicated TCP port (COM1 → 502, COM2 → 503, COM3 → 504), and supports up to 32 simultaneous TCP master connections. This allows multiple HMI, SCADA, or PLC masters to access slave devices on the same serial bus concurrently without conflict. The built-in read-cache function stores previous Modbus requests and responses in a memory buffer; when multiple masters send identical requests, the cached response is returned immediately — significantly reducing serial port loading and improving TCP response time.
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 installation. A DC jack input (+12–48 VDC) is also available as an alternative. Ultra-low power consumption of 0.07 A at 24 VDC minimizes operating costs in large-scale multi-gateway deployments.
The built-in HTTP web server enables browser-based configuration of IP settings (DHCP/Static), network parameters, and serial port settings without additional software. Dual watchdog protection ensures continuous 24/7 operation — the CPU watchdog resets the firmware if it operates abnormally, while the host watchdog resets the unit if communication with the host is lost within a predefined timeout period.
The tGW-732 supports ESD protection of ±4 kV. The isolated variant (tGW-732i) provides 3,000 VDC signal isolation for enhanced noise immunity in electrically demanding environments. With a wide operating temperature range of -25°C to +75°C, the tGW-732 operates reliably in diverse industrial conditions and is RoHS compliant.
