Rotating equipment reliability

12 min

Condition monitoring across a fleet of six machines in the balance of plant: boiler feed pumps, a cooling water pump, an induced draft fan, a cooling tower fan and an instrument air compressor. Six machines and 90 tags published over Sparkplug B.

Operator view	port 4015
MQTT broker	port 5025
Devices and tags	6 machines, 90 tags
Litmus Edge driver	Sparkplug B over MQTT
Image	rotating-equipment-demo

Scenarios

The impulse before the trend. Bearing damage shows up first as impulsiveness in the vibration signal, not as a rise in overall level. By the time the trend moves, the decision has already been made for you.

Bearing prognosis on the Edge. The health figure and the estimate of remaining life are produced on the Edge from the stream, not in a cloud from a daily average.

One model, any machine. A single twin model serves pumps, fans and a compressor alike. Adding the seventh machine is configuration rather than engineering, which is the whole argument for condition monitoring as a horizontal.

Containers

Sparkplug B is publish and subscribe, so it needs a broker, and a Litmus Edge does not broker MQTT: it subscribes as a host application. Mosquitto therefore ships beside the simulator and the Edge's Sparkplug B client connects to it on 5025.

That has one practical consequence. This solution cannot be started as a single container, so it is deployed with the compose file below rather than through a docker run, and the Solutions provisioner will decline to start it from a card and say so.

mosquitto.conf must sit beside the compose file. Mosquitto 2 binds loopback only and refuses anonymous clients without it, so a missing config file gives you a broker that comes up and rejects every connection.

What it creates on Litmus Edge

Six DeviceHub devices, one per machine, with 90 tags arriving over Sparkplug B. One shared Digital Twin model with an instance per machine. Analytics groups behind the fleet health, ISO zone and impulsiveness figures.

Requirements

Litmus Edge 4.0.x, reachable over HTTPS from the host running the solution

An API token for that Edge, or a username and password, or a client id and secret

Docker, and Docker Compose for the compose deployment

A network path in both directions: the solution reaches the Edge's API, and the Edge reaches this host on the protocol port

Deploy

The solution ships two ways. Use the registry if the host can reach Google Artifact Registry, and the downloaded archive if it cannot.

Option 1: pull from the registry

Requires a read-only registry credential, supplied by Litmus separately.

cat key.json | docker login -u _json_key --password-stdin https://us-docker.pkg.dev

Save this as docker-compose.yml:

services:
  mosquitto:
    image: eclipse-mosquitto:2
    container_name: rotating-mosquitto
    restart: unless-stopped
    ports:
      - target: 1883
        published: 5025
        protocol: tcp
    volumes:
      - type: bind
        source: ./mosquitto.conf
        target: /mosquitto/config/mosquitto.conf
        read_only: true
    healthcheck:
      test: ["CMD-SHELL", "nc -z 127.0.0.1 1883"]
      interval: 10s
      timeout: 3s
      retries: 5

  rotating-equipment:
    image: us-docker.pkg.dev/litmus-customer-facing/litmus-solutions/rotating-equipment-demo:0.3.0
    container_name: rotating-equipment-demo
    restart: unless-stopped
    depends_on:
      mosquitto:
        condition: service_healthy
    ports:
      - target: 4015
        published: 4015
        protocol: tcp
    environment:
      # Fill these in.
      EDGE_URL: "${EDGE_URL:-}"
      EDGE_API_TOKEN: "${EDGE_API_TOKEN:-}"
      SIM_HOST: "${SIM_HOST:-auto}"
      APPLY_ON_START: "${APPLY_ON_START:-1}"
      EDGE_VERIFY_TLS: "${EDGE_VERIFY_TLS:-0}"
      HTTP_PORT: "4015"
      MQTT_HOST: "mosquitto"
      MQTT_PORT: "1883"
      MQTT_PUBLIC_PORT: "5025"
      SPARKPLUG_GROUP: "Plant01"
      SPARKPLUG_NODE: "BalanceOfPlant"
      AUTOSTART: "1"
      TICK_SECONDS: "0.1"
      SEED: "11"
      LOG_LEVEL: "INFO"

EDGE_URL=https://10.0.0.5
EDGE_API_TOKEN=your-token
SIM_HOST=10.0.0.9

docker compose up -d

Open http://localhost:4015.

The page stays on its waiting panel until the Edge carries this solution's devices. That is deliberate: the simulation does not tick and no value is shown until Litmus Edge is verified to hold the devices and poll them, so nothing on screen can be mistaken for data that never made the trip. With APPLY_ON_START at its default of 1 the solution configures the Edge itself on startup, which takes 30 to 60 seconds. If you set it to 0, or the apply failed, press Apply to Edge in the page header.

Option 2: load the downloaded archive

Download rotating-equipment-demo-0.3.0-amd64.tar.gz from the solution's page on portal.litmus.io. The archive is the container image, not a source bundle, and needs no registry access.

docker load -i rotating-equipment-demo-0.3.0-amd64.tar.gz

docker load prints the image it added:

Loaded image: us-docker.pkg.dev/litmus-customer-facing/litmus-solutions/rotating-equipment-demo:0.3.0

That reference is the one the compose file above already names, so the same docker-compose.yml and .env now work offline with no docker login:

docker compose up -d

This solution is two containers, the simulator and an MQTT broker, so it has no single docker run form. Use the compose file above after loading the image; the broker image is public and pulls from Docker Hub.

Configuration

Variable	Default	What it does
EDGE_URL	the Docker host	Litmus Edge to configure
EDGE_API_TOKEN	unset	token for that Edge. Or a username and password, or a client id and secret
SIM_HOST	auto	address the Edge uses to reach the broker
APPLY_ON_START	1	configure the Edge on startup
EDGE_VERIFY_TLS	0	1 checks the Edge's certificate
MQTT_HOST	mosquitto	how this container reaches the broker: the service name
MQTT_PORT	1883	the broker's own internal port
MQTT_PUBLIC_PORT	5025	how the Edge reaches the broker
SPARKPLUG_GROUP	Plant01	Sparkplug group id
SPARKPLUG_NODE	BalanceOfPlant	Sparkplug edge node id

MQTT_HOST and MQTT_PUBLIC_PORT answer different questions and are easy to conflate. The first is how the simulator reaches the broker, on the container network. The second is how Litmus Edge reaches it, and it is the one that goes into the DeviceHub template. Putting the container name in the template gives you devices that come online and never read a value.

Operator view

Fleet health across the top, then the six machines with their health scores and ISO zone. Click a machine to inspect its signal: the vibration stream the Edge features, with the RMS and the impulsiveness that moves first.

Every value on the page is read back from Litmus Edge rather than from the simulator, and the page says how many reads it has made and how old the newest is. What you are looking at took the full trip through the device.

Faults include a bearing defect developing, lubrication loss, cavitation on a pump and an imbalance.

Apply and remove

docker compose down

Use Clean up in the Solutions provisioner to remove what it created on the Edge.

Support

[email protected]