IEC 61850 MMS · Modbus TCP · MQTT

Learn the protocols. Bridge relay data. Build a clean HMI route.

ARServer is a Windows engineering gateway and information center for turning selected IEC 61850 IED values into practical Modbus TCP maps and MQTT topics for HMI, SCADA, DCS, FAT, relay bench, dashboard, and substation automation workflows.

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Source: IEC 61850 MMS
Outputs: Modbus TCP + MQTT
Use case: HMI / SCADA / FAT
License: Apache-2.0

IED sourceOCR7SR12 / MMS :102

Associated · runtime cache healthy

IEC ObjectValueQ

XCBR1.Pos.stValClosedGood

PTOC1.Op.generalFalseGood

MMXU1.A.phsA.cVal132.6Fresh

Modbus TCP30001 → CB Position

MQTTarserver/IED/tag/state

Learning center

A practical starting point for IEC 61850, Modbus TCP, and MQTT.

Use ARServer as a product and as a learning map. The goal is to make protocol relationships clear before users start mapping real values.

Protocol 01

IEC 61850 and MMS

Understand IEDs, logical nodes, data objects, data attributes, function constraints, SCL files, and why MMS commonly uses TCP port 102.

Protocol 02

Modbus TCP for HMI/SCADA

Learn why classic DCS, HMI, and SCADA tools prefer stable register maps, status bits, input registers, and deterministic address planning.

Protocol 03

MQTT for data platforms

Learn how topic names, JSON payloads, quality, timestamps, and broker routing make relay data usable for dashboards and middleware.

Use case center

Find the workflow that matches your real integration problem.

ARServer can be used as an HMI/SCADA bridge, a FAT/SAT visibility layer, or an MQTT publishing route. Each use case explains what to map, what to validate, and what to avoid.

Use Case OverviewChoose between HMI/SCADA, FAT/SAT, and MQTT Dashboard workflows.HMI/SCADA IntegrationExpose selected IEC 61850 values as stable Modbus TCP points for HMI, SCADA, or DCS.FAT/SAT Relay BenchValidate source values, Modbus mapping, MQTT payloads, and stale behavior during test workflows.MQTT DashboardPublish relay values with quality and timestamp context to broker-based dashboards and middleware.

Zero to running

From relay IP or SCL file to a working Modbus/MQTT gateway.

The documentation path is designed for a first-time user: install, add source, select signals, validate, map, publish, and troubleshoot.

Install and open

Run ARServer on Windows and understand what the workspace shows before starting runtime.

Add IED source

Start from live relay IP over MMS port 102 or from SCL/CID/SCD/ICD/IID engineering files.

Validate signals

Select SCADA-friendly points, probe readability, and keep value, quality, timestamp, and stale status visible.

Publish outputs

Expose stable Modbus TCP points and optional MQTT topics for HMI, SCADA, dashboards, or test tools.

Architecture

Relay data enters once, then fans out to the systems that need it.

ARServer sits between IEC 61850 IEDs and practical consuming systems. It keeps the relay read path controlled, then exposes selected values to classic control systems through Modbus TCP and modern data workflows through MQTT.

Relay / IED remains the source of truth over IEC 61850 MMS.
ARServer validates selected values before publishing outputs.
DCS, HMI, and SCADA tools can poll the Modbus TCP server.
IoT dashboards, middleware, or historians can subscribe through MQTT.

SourceRelay / IEDIEC 61850 server

IEC 61850 MMS · port 102

GatewayARServerruntime cache · quality · timestamp · mapping

Modbus TCP

MQTT

Classic control layerDCS · HMI · SCADApoll registers / status points

Data platform layerIoT · Historian · Dashboardsubscribe topics / JSON state

Product screenshots

Actual ARServer workflow screens.

Screenshots help new users understand the start workspace, live IEC values, Modbus server map, and MQTT topic routing before installing.

ARServer start workspace — **Start workspace**Add the first IEC 61850 IED and begin the gateway workflow.

ARServer live IEC 61850 values table — **Live IEC 61850 values**Values, quality, object path, and inferred type stay visible.

ARServer Modbus TCP mapping table — **Modbus server map**Selected IEC signals become clear Modbus points for HMI polling.

ARServer MQTT topics screen — **MQTT topic routing**Publish value, quality, status, and state payloads to broker topics.

Product docs

The documentation path for learning and using ARServer.

Open the Markdown preview pages when you need clean reading without raw Markdown syntax.

Quick StartRelay IP or SCL file to running gateway.TroubleshootingConnection, discovery, Modbus, MQTT, and stale value checks.Validation MatrixBench checklist for FAT, lab, and simulated evaluation.RoadmapNative IEC 61850 milestones and report-ready direction.DeploymentGitHub Pages, SEO files, and documentation publishing notes.Security PolicyResponsible handling for engineering gateway security concerns.

FAQ

Common questions before trying ARServer.

What is ARServer in simple terms?

ARServer is a Windows gateway that reads selected IEC 61850 relay or IED values and republishes them as Modbus TCP registers and MQTT topics for HMI, SCADA, DCS, dashboard, or test tools.

Is ARServer a relay test set?

No. It is a gateway and engineering workspace for selected data reading, mapping, publishing, and validation.

Can it connect to a real relay or IED?

Yes, when the relay, network, and supported IEC 61850 services allow MMS communication over TCP port 102. Validate on a bench or FAT network first.

Do I need an MQTT broker?

Yes for MQTT output. Modbus TCP output does not require MQTT.

Why are quality and timestamp important?

A Boolean value without quality and timestamp can mislead operators. ARServer keeps value context visible so users can see whether a point is fresh, stale, good, or invalid.

Start small, validate clearly

Build one clean IEC 61850 to Modbus/MQTT mapping, then expand with confidence.

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