Nthytronic Group iRTUe I/O Expansion Module

The configuration of iRTUe is completed through the iConf tool. This tool runs on a Windows PC and can be connected to the device via Ethernet or serial port to achieve:

Set IP address and GOOSE subscription/publishing parameters

Configure the debounce time and counter mode for digital input

Calibrate the zero and full scale of analog inputs

Define Modbus register mapping (function code, address, data type)

Import/export SCL files (future firmware support)

Online monitoring of I/O status and GOOSE communication quality

For rapid on-site deployment, the Modbus address and GOOSE multicast group can be set using the side dip switch, and basic communication parameter configuration can be completed without the need for a computer.

Selection and Ordering Guide

During the project design phase, the iRTUe model should be determined according to the following steps:

Determine the required type and quantity of I/O

For example: 32 DIs, 12 DOs, and 4 AIs are required → optional # DIRI (24DI+8DO) plus one # DIDI (24DI) or # AIAI (8AI)? Note that each iRTUe can only accommodate two I/O cards, so it needs to be combined reasonably. If there are many points, multiple iRTUes can be cascaded.

Select power supply voltage range

The DC control voltage inside the station is usually 110V or 220V, and a wide range type (W) should be selected. If it is a 24V system, choose the 24 type.

Select Ethernet interface type

Copper cable (RJ45): suitable for short distances (≤ 100 m) inside cabinets

Fiber optic (ST/SC): suitable for cross spacing, anti electromagnetic interference, or long-distance (≥ 2 km) connections

Confirm if it is necessary to communicate analog quantities (OOQI)

If it is necessary to measure bus voltage, line current, frequency, harmonics, etc., the # OOQI configuration must be selected.

Confirm if timestamp and SOE are required

All numerical inputs come with a 1ms timestamp, no additional options are required.

Ordering example: iRTUe # DIRI-W-RJ45 represents 24DI+8DO, wide range power supply, dual RJ45 Ethernet ports.

Key points for installation and debugging

10.1 Mechanical Installation

Install using standard DIN rails (35 mm) to ensure adequate heat dissipation space (at least 50 mm above and below).

When connecting I/O cables, use the accompanying MVSTBR 2.5 series plug-in terminals for easy maintenance. Each group of 8 digital inputs shares a common terminal (COM), and relay outputs are grouped every 2 channels. Before wiring, the polarity of the common terminal needs to be checked.

10.2 Communication Wiring

Ethernet: Use shielded CAT5e or higher grade Ethernet cables, and clean the fiber optic end face.

EXP422 serial port: Use shielded twisted pair cables, with a maximum distance of no more than 1200 meters. It is recommended to add terminal resistors at the end.

10.3 Configuration Process

Connect the device through iConf and set the IP address (if using Ethernet) or Modbus serial port parameters.

Configure digital input debounce time (e.g. 2 ms for fast signals and 20 ms for mechanical contacts).

Calibrate analog input: Apply 4.00 mA and 20.00 mA standard currents to the 4-20 mA circuit and record the calibration values.

Configure GOOSE subscription: Specify the GOOSE control block reference (GoCBRef), dataset members, and data type to listen on.

Create Modbus mapping table: Map internal I/O points to Modbus register addresses (supports 0x/1x/3x/4x).

Save the configuration and restart the device, monitor the GOOSE communication status indicator light.

10.4 Troubleshooting

GOOSE cannot receive data: check VLAN settings, multicast group address, switch IGMP listening configuration.

Digital input signal jitter: increase the time of the debounce filter; Check if the input voltage is close to the threshold area.

Relay output unable to operate: Measure coil power supply (24V from autonomous station or external), check if the output is logically locked.

Inaccurate timestamp: Confirm whether the NTP server is reachable and check the time difference between iRTUe and the main station.