iRTUe – Distributed I/O for Gateways & RTUs

iRTUe remote expan­sion units pro­vide dig­i­tal and ana­log I/Os with IEC 61850 GOOSE
  • IEC 61850 GOOSE (Gener­ic Object Ori­ent­ed Sub­sta­tion Events) com­mu­ni­ca­tion (Publisher/subscriber)
  • High speed pro­cess­ing time — type 1A class per­for­mance P2/3
  • Flex­i­ble con­fig­u­ra­tion of two I/O cards per unit with dig­i­tal & ana­log inputs and relays
  • Sate-of-the-art & secured tech­nol­o­gy for advanced automa­tion func­tion­al­i­ties like load shed­ding or interlocking
  • Ser­i­al (EXP422) or dou­ble Eth­er­net port (cop­per or fiber) to con­nect to iRTUs/iGWs or any oth­er third par­ty mas­ter unit
  • Mul­ti­cast MAC addresses
  • Time syn­chro­niza­tion via PTP/IEEE1588 or NTP
  • Use GGIO data mod­els or cus­tom SCL files 
  • Pow­er qual­i­ty mea­sure­ments with the spe­cialised iRTUe‑Q

Our remote I/O expan­sion units com­mu­ni­cate with IEC 61850 GOOSE, allow­ing to extend and dis­trib­ute the acqui­si­tion and com­mand capa­bil­i­ties of  IEC 61850 mas­ters (GOOSE sub­scribers). We offer flex­i­ble I/O board con­fig­u­ra­tions to ful­fill any appli­ca­tion require­ment, mak­ing the iRTUe the per­fect choice to both set-up and retro­fit elec­tri­cal com­mu­ni­ca­tion networks. 

Con­tem­po­rary sub­sta­tion automa­tion calls for advanced I/O mod­ules to pro­vide mod­ern ser­vices such as inter­lock­ing or load shed­ding. These func­tion­al­i­ties rely on state-of-the-art char­ac­ter­is­tics, which can­not be realised with ser­i­al com­mu­ni­ca­tion media and old pro­to­cols. For this rea­son, the iRTUe exe­cutes IEC 61850 GOOSE mes­sag­ing in a pro­cess­ing time under 3ms. 

They con­nect via dou­ble Eth­er­net (RJ45, ST or SC) or ser­i­al (EXP422) port and are syn­chro­nized with IEEE 1588 (PTP) to ensure opti­mal time accu­ra­cy. This allows the iRTUe to com­mu­ni­cate with any oth­er equip­ment in the net­work: for instance RTUs, gate­ways, oth­er iRTUe mod­ules and third-par­ty IEDs on the sub­sta­tion process bus.

iRTUe I/O Expansion Unit

  • Ser­i­al (1) RS-422 port to con­nect to iRTU&iGW devices with ModbusRTU
  • Eth­er­net (2) 10/100BaseTX ports, RJ45 or FX100 fiber optics with ST or SC connectors
  • Up to 48 Dig­i­tal Inputs, 16 Relays and 16 Ana­log Inputs
  • Pro­to­cols IEC 61850 GOOSE mes­sag­ing & Mod­bus RTU

Features & Functionalities


Time Syn­chro­niza­tion via NTP and IEEE 1588 (PTP client)


Sup­ports PRP, HSR and RSTP redun­dan­cy protocols


Time response under 3ms (type 1A class P2)


Freely dis­trib­utable & con­fig­urable Inputs & Outputs


Mul­ti­ple con­nec­tion options


Made for advanced IEC 61850 sub­sta­tion automa­tion schemes

iRTUe Substation Application

Exam­ple schema

Schema distributed I/O extensions GOOSE

Technical Features


GOOSE com­mu­ni­ca­tion works with enhanced retrans­mis­sion mech­a­nisms on a publisher/subscriber basis, allow­ing P2P com­mu­ni­ca­tion between iRTUe and IEDs with a pro­cess­ing time under 3ms (per­for­mance class P2).

IEC 61850 GOOSE also fea­tures strong VLAN and pri­or­i­ty tag­ging func­tion­al­i­ties via IEEE 802.1Q to send mes­sages effi­cient­ly across com­plex phys­i­cal net­works. Com­bined with a sub­sta­tion-wide Eth­er­net LAN, it enables flex­i­ble and sophis­ti­cat­ed log­ic schemes for sub­sta­tion pro­tec­tion and automa­tion, such as inter­lock­ing and load shedding.

Since these sys­tems are based on soft­ware con­fig­u­ra­tions rather than hard­wired sig­nal paths, they are more cost-effec­tive, eas­i­ly extend­able and on demand recon­fig­urable, mak­ing them high­ly adap­tive to chang­ing sub­sta­tion con­fig­u­ra­tions and net­work topologies.

The oper­a­tional reli­a­bil­i­ty of these schemes is sig­nif­i­cant­ly enhanced by GOOSE’s con­tin­u­ous and inher­ent super­vi­sion of the com­mu­ni­ca­tion and the message’s data integrity.

With its strong IEC 61850 GOOSE capa­bil­i­ties, the iRTUe is the per­fect I/O exten­sion to employ these advantages.

Standards and Compliance

The diverse back­grounds of our part­ners and clients from all over the world have helped us gath­er state-of-the-art know-how and first­hand expe­ri­ence in a great vari­ety of ener­gy appli­ca­tions. This joined knowl­edge is the foun­da­tion of our opti­mized iRTU/GW fam­i­ly, which has a proven track record of being par­tic­u­lar­ly effec­tive and resis­tant for a diverse range of appli­ca­tions and harsh envi­ron­ments belong­ing to the ener­gy industry.

As a result, the iRTUe meets the require­ments of exten­sive stan­dards, such as IEC61850‑3, IEC60870‑2–1 & IEC60255-26.

Inputs and Outputs

Dig­i­tal Inputs & Outputs

Each input can be defined as input or as a counter and have an indi­vid­u­al­ly con­fig­ured debounce fil­ter. One iRTUe unit can pro­vide up to 48 iso­lat­ed dig­i­tal inputs with a 2.5kVrms iso­la­tion and a 1  ms time­stamp accu­ra­cy. The units come in stan­dard input volt­ages of 24, 48, 125 or 220 Vdc.

On the out­put side, one unit can pro­vide up to 16 dry con­tact electro­mechan­i­cal relay out­puts. Their max­i­mum break­ing capac­i­ty 8A at 220Vac and 8, 0.3 and 0.12A at 30, 110 and 220Vdc respec­tive­ly. Group­ing relay out­puts in blocks of 2.Isolation between sole­noid and con­tacts: 6 kV.

Ana­log Inputs

One iRTUe unit can can pro­vide up to 16 ana­log inputs with an iso­la­tion of 2.5kVrms. They are offered with a range of 4 20 mA and +/-10 Vdc and have an accu­ra­cy of 0.15%.

Pow­er Qual­i­ty Analysis

With 3 volt­age and 3 cur­rent inputs, the iRTUe#Q fam­i­ly can mea­sure all pow­er qual­i­ty para­me­ters (fre­quen­cies, cur­rents, phas­es etc.) and store the data in COMTRADE files. 

Simple Configuration

iRTUe address­es, in both Mod­bus and GOOSE, can be eas­i­ly con­fig­ured using the side microswitch­es. For GOOSE, the default mul­ti­cast group is set to zero (mod­i­fi­able with iConf).

Models Overview

Each iRTUe aux­il­iary unit includes up to two I/O cards with rat­ed input volt­ages of: 24 Vdc, 48 Vdc, 125 Vdc or 220Vdc (oth­er ranges upon request). They can be assem­bled as follows:

iRTUe#D1D1: 48 Dig­i­tal Inputs.

iRTUe#R1R1: 16 Relay Outputs.

iRTUe#A1A1: 16 Ana­log Inputs (0–20mA)

iRTUe#D1R1: 24 Dig­i­tal Inputs + 8 Relay Outputs

iRTUe#D1A1: 24 Dig­i­tal Inputs + 8 Ana­log Inputs (0–20mA)

iRTUe#R1A1: 24 Dig­i­tal Out­puts + 8 Ana­log Inputs (0–20mA)

iRTUe#Q: 3 volt­age inputs at 110Vac through four pin 5.08mm ter­mi­nal block con­nec­tors + 3 cur­rent inputs for 1A cur­rent trans­form­ers, via 6 pin 5.08mm ter­mi­nal block connectors

iRTU#Q2: 3 com­bined inputs using an RJ45 con­nec­tor, for pas­sive smart sen­sors based on IEC 60044–7/8

Oth­er con­fig­u­ra­tions upon request


General Characteristics

Pow­er sup­ply  W : wide range, 32 — 250Vdc / 80 — 250Vac (2.5kVrms iso­la­tion)  24 : 19.5–60Vdc (2.5kVrms isolation)

MTBF 177,000h (one hun­dred sev­en­ty sev­en thou­sand hours)

Envi­ron­men­tal Oper­at­ing tem­per­a­ture : ‑25ºC to +70ºC

IEC 60068–2‑1, IEC 60068–2‑2, IEC 60068–2‑3, IEC 60068–2‑14, IEC 60068–2‑30, IEC 60068–2‑38

Vibra­tion & shock test IEC 60068–2‑6, IEC 60068–2‑7

Phys­i­cal exter­nal dimen­sions: 173 x 78.4 x 137 mm (HxWxD)
IP30 enclo­sure with DIN Rail mounting

Con­fig­u­ra­tion sim­ple con­fig­u­ra­tion with iConf tool

CPU 32 bits micro­con­troller @ 40MHz

Digital Inputs

Iso­la­tion 2.5 kVrms

Acti­va­tion ON when Vi>85%Vn | OFF when Vi<60%Vn | oth­er lev­els upon request

Con­nec­tors MVSTBR 2,5 9 pins — group­ing dig­i­tal inputs in iso­lat­ed blocks of 8 inputs and one com­mon terminal


Relay Outputs

Iso­la­tion 6 kVrms

Con­tact Dry

Con­nec­tors MVSTBR 2,5 4 pins – group­ing relay out­puts in blocks of 2

Break­ing Capac­i­ty 8A @ 220Vac – 8/0.3/0.12A @ 30/110/220Vdc


Communication Features

Ser­i­al (1) RS-422 port to con­nect to iRTU&iGW devices with ModbusRTU
Eth­er­net (2) 10/100BaseTX ports, RJ45 or FX100 fiber optics with ST or SC connectors
Time Syn­chro­niza­tion IEEE 1588 (PTP-Pre­cise Time Pro­to­col) client
Pro­to­cols IEC 61850 GOOSE mes­sag­ing or Mod­bus TCP/RTU
IEC 61850 Log­i­cal Nodes GGIO pre­de­fined (future firmware upgrades will allow any SCL file)
Time response under 3ms fol­low­ing the per­for­mance test in IEC 61850 (type 1A class P2)

Analog Inputs

Iso­la­tion 2.5 kVrms

Accu­ra­cy 0.15% after calibration

Con­nec­tors MVSTBR 2,5 4 pins – group­ing ana­log inputs in blocks of 2

Ranges 4–20mA (+/-20% tol­er­ance), +/-10Vdc

EMC Standards

IEC 60950–1, IEC 60255–5:2000, EC 60255–22:2000, EN 55022, IEC 61000–6‑4, IEC 61000–6‑5, IEC 61000–4‑2, IEC 61000–4‑3, IEC 61000–4‑4, IEC 61000–4‑5, IEC 61000–4‑6, IEC 61000–4‑8, IEC 61000–4‑9, IEC 61000–4‑10, IEC 61000–4‑12, IEC 61000–4‑16, IEC 61000–4‑17, IEC 61000–4‑18, IEC 61000–4‑29

iGrid Masters for iRTUe Units

iGW – The Perfect Master for iRTUe Units

The iGW is a pow­er­ful and reli­able sub­sta­tion gate­way, able to run either in stand­alone or redun­dant modes, car­ry­ing 4 ser­i­al ports and an (option­al) embed­ded Eth­er­net switch for 2 addi­tion­al Eth­er­net ports (total of 4).

iGWlite – The “Litest” Gateway for iRTUe

The iGWlite comes with 1 Eth­er­net, 1 RS485/RS422 and an option­al RS-232 port (cop­per or fiber) or a 2G/3G/4G modem tak­ing lit­tle space on a DIN-Rail, but still employ­ing the full iGrid pro­to­col suite.

iRTU – The Gateway with Integrated I/Os

The iRTU is an intel­li­gent and scal­able bay con­troller with inter­nal and con­fig­urable I/O capa­bil­i­ties for direct data acqui­si­tion, pow­er­ful pro­to­col con­ver­sion (incl. IEC 61850), high-pre­ci­sion time­stamp­ing and an option­al embed­ded Eth­er­net switch.

Power Quality Analyzer & I/O Expansion Unit

  • High-accu­ra­cy 3‑phase measurements
  • 3 Cur­rent Inputs
  • 3 Volt­age  Inputs
  • Fre­quen­cy and Pow­er fac­tor measurements
  • Option­al I/O card configurations
  • EXP-422 ser­i­al connection
  • iRTUeQ2: 3 com­bined inputs, using RJ45 con­nec­tor, for pas­sive smart sen­sors based on IEC 60044–7/8

Features & Functionalities


Mea­sure­ments accord­ing to IEC 60044–8


Con­fig­urable Sag & Swell Alarms


Con­fig­urable Over­cur­rent Alarms




Mod­bus RTU & IEC 61850 GOOSE


High-accu­ra­cy time syn­chro­niza­tion via NTP


Mul­ti­ple con­nec­tion options


Super com­pact DIN-rail mounting

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    Common iRTUe Applications

    Sub­sta­tion Automation

    PLC & PAC I/O Expansion

    RTU I/O Expansion

    Gate­way I/O Expansion

    Pow­er Qual­i­ty Measurement

    Gen­er­a­tion Dispatch

    Inter­lock­ing with GOOSE

    Gen­er­a­tion Control

    Sub­sta­tion Data Acqui­si­tion and Control

    Elec­tric­i­ty Dis­tri­b­u­tion Networks

    Intel­li­gent Load Shedding

    Rail­way Data Collection

    HV SAS with Modbus

    In this sub­sta­tion automa­tion project two dif­fer­ent con­fig­u­ra­tions of iRTUe units acquire data of four bays oper­at­ing at 230kV and ten bays at 33kV. The iGW reports this data to the con­trol cen­ter and to the iCon­trol SCADA HMI via IEC 60870–5‑104.

    MV Grid Automation with IEC 61850

    In this project the iRTUe units help the iRTU col­lect data data via IEC 61850 in order to auto­mate 9 medi­um volt­age sub­sta­tions at the Sabi­ha Gökçen Air­port (Turkey)

    iGW-VM – unlimited control

    The freely scal­able iGW-VM sup­ports all archi­tec­tures using Win­dows or Lin­ux, act­ing as a sub­sta­tion gate­way, bay con­troller, RTU or com­mu­ni­ca­tion front-end for SCADA sys­tems. The iGW-VM is thus the per­fect soft­ware choice for projects with a predetermined/preferred hard­ware or a large grid to cov­er (high num­ber of datapoints).

    iControl SCADA

    High-per­for­mance SCADA for the visu­al­iza­tion and con­trol of sub­sta­tion data. It is able to run either in client/server or stand­alone modes, pro­vid­ing advanced func­tion­al­i­ties such as hot-stand­by redun­dan­cy, auto­mat­ic line col­or­ing, events noti­fi­ca­tion (via e‑mail and sms), SQL log­ging, and reports generation.

    Sub­sta­tion Automa­tion with IEC61850

    HV Sub­sta­tions

    MV Dis­tri­b­u­tion Grids

    Rail­way Automation

    Pro­to­col Conversion

    Smart Meter­ing

    Wind Farm Generation

    Hydro­elec­tric Generation

    Pho­to­voltaics Generation

    Do you need more information?

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      Basic infor­ma­tion about our data protection:

      Insti­tu­tion in charge: IGRID SL. Pur­pos­es of data pro­cess­ing: Cus­tomer con­tact. Archived data loca­tion: Raio­la Net­works SL (UE). Per­son­al data retain peri­od: Until removal request. Rights: You can exer­cise your rights of access, rec­ti­fi­ca­tion, can­cel­la­tion and opposition.