RETERMINT01 – RETERMINAL DM Interface Board

RETERMINT01 is an interface board for the reTerminal DM by Seeed Studio. It adds a galvanically isolated industrial interface — 3× RS-485 bus, isolated 24 V power supply and the ability to remotely switch off the power of a connected field device via GPIO. All communication on the bus side is fully galvanically isolated from the reTerminal DM logic.

The board connects directly to the 40-pin GPIO header of the reTerminal DM.

Features

• 3× RS-485 – galvanically isolated half-duplex channels (ADM2483xRW), up to 500 kbps
• Isolated 24 V DC/DC – 30 W Traco Power THN 30-2423WI, software-controllable (default OFF)
• Remote power switching – PS1 output controlled via PWR_OFF GPIO signal (active LOW)
• 5 V power module – TI TPSM33606S5, powers the isolated RS-485 bus side
• u-blox NEO-M9N GPS – with u.FL antenna connector, USB configuration port and 1 F supercapacitor backup
• Shielded RJ45 with LEDs – for RS-485 field bus connection
• ESD & overvoltage protection – SM712 TVS on every RS-485 channel, USBLC6-2SC6 on GPS USB
• 2× 1 A fuse – on 24 V input paths

Schematic