MQTT Simulator in 5 Minutes with SPX: Smart Building Pack Quickstart

This is a hands-on quickstart. For a technical overview of MQTT features (QoS 0/1/2, retained, LWT/availability, mqtt vs mqtt-ha), see MQTT Simulator.

Simulation timeline for the “Summer Storm” scenario — spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt. The model drives storm-like weather dynamics and publishes updated sensor telemetry over MQTT (via the WAGO PFC200 gateway and Vaisala WXT530), allowing you to validate topic updates, state changes, and downstream automation behavior under rapidly changing conditions.

In this guide you’ll spin up a “real device” MQTT simulation in about five minutes using SPX and the Smart Building Pack. The idea is simple: install SPX, select the Smart Building Pack (which brings all required services, including an MQTT broker like Eclipse Mosquitto), open the SPX UI, launch a ready-made MQTT device instance, and verify it’s alive either with a lightweight MQTT client (like the free MQTT Explorer) or via a preconfigured Home Assistant dashboard.

Tip #1 - Install SPX and select Smart Building Pack

1. Get your Product Key + installer package

   1. Log in and open Product & Keys: https://www.simplephysx.com/keys

   2. Copy your SPX Product Key

   3. Download the installer package (e.g. spx-examples-<version>.zip)

2. Extract the ZIP

   1. Unzip the package into a dedicated folder (e.g. spx-examples-<version>/). You should see platform launchers like spx-setup.*.

3. Run the Setup Wizard (spx-setup.*)

   1. From the extracted folder, start the launcher for your OS:

      1. Windows: double-click spx-setup.bat

      2. macOS: double-click spx-setup.command

      3. Linux desktop: double-click spx-setup.desktop

      4. Terminal (macOS/Linux): ./spx-setup.sh

4. In the wizard: select Smart Building Pack + paste your key

   1. Select Smart Building Pack (ENTER accepts recommended defaults)

   2. Paste your SPX Product Key when prompted

   3. Review the summary and choose Start the stack now

   
   

Once the pack is installed, SPX sets up the services you need for an end-to-end demo environment — including an MQTT broker (e.g., Eclipse Mosquitto) and a ready-to-use Home Assistant instance for validation. Note: For the full, always up-to-date installation instructions (including prerequisites and OS-specific launchers), see the SPX Installation Guide in the docs: https://docs.simplephysx.com/getting-started/installation-guide.

Tip #2 - Open the SPX UI

Open: http://localhost:3000

SPX web UI (localhost:3000): Smart Building Pack instance catalog — choose a ready-to-run simulator such as spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt.

You should see the SPX interface with a list of available instances from the Smart Building Pack.

Tip #3 - Start a real-device MQTT simulation (one click)

• From the list of available instances, select:

  spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt

From the Smart Building Pack list, select spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt and click Open/View Instance to access the instance details and controls.

• Open the instance. At this point you already have a working MQTT simulation of a real-world style device stack (gateway + weather station), ready for testing.

Instance details for spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt — status, MQTT connection info, live attributes, and scenario controls (e.g., Summer Storm*) in one place.*

Tip #4 - Verify it’s alive (two options)

Option A: Inspect topics with MQTT Explorer (free)

Use MQTT Explorer (or any MQTT client) to connect to the local broker and confirm that the simulator is publishing:

• weather telemetry topics updating over time

• retained “state-style” topics where applicable

• availability/LWT-style behavior depending on the instance configuration

Tip: If you don’t see messages instantly, wait ~10–20 seconds — many telemetry devices publish on an interval.

Option B: Use the included Home Assistant dashboard

Open the preconfigured Home Assistant UI:

http://localhost:8123/lovelace/spx

Home Assistant test dashboard (localhost:8123/lovelace/spx) showing live entities fed by SPX — instantly verify your MQTT simulator via a real smart-building UI.

This dashboard is set up specifically for testing. You can immediately observe how the simulator affects sensors, entities, and automations — without building any HA config yourself.

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Expected outcome (what “done” looks like)

Within minutes you should have:

• SPX running locally

• Smart Building Pack installed (services included, MQTT broker ready)

• The instance spx_weather_gateway_wago_pfc200_vaisala_wxt530_mqtt running

• Visible live telemetry in MQTT Explorer and/or on the Home Assistant dashboard

From here, you can start “playing”: explore attributes, run scenarios (e.g., Summer Storm), and validate how downstream systems behave under changing conditions.

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Next: customize and extend (coming next)

Next we’ll take this same instance and:

• Tweak the model in the editor and reload it

• Generate a new variant via an LLM workflow

• Run scenario-driven tests and capture reproducible baselines