MQTT Mode

MQTT mode allows v2c-any to publish power data directly to MQTT topics that V2C wallboxes subscribe to. This enables push-based, event-driven updates with lower latency compared to REST polling.

When to Use MQTT Mode

Use MQTT mode when:

Your V2C wallbox is configured for MQTT integration
You have an existing MQTT broker (Mosquitto, HiveMQ, etc.)
You want push-based, event-driven updates
You need lower latency or more frequent updates than REST polling allows
You're integrating with other MQTT-based home automation systems
You want to bridge multiple MQTT sources

Don't use MQTT mode when:

Your V2C wallbox is only configured for Shelly REST polling (use REST mode)
You don't have an MQTT broker and don't want to set one up
Your data sources don't update frequently enough to benefit from push updates

MQTT Topics

v2c-any publishes to the following topics that V2C wallboxes subscribe to:

Topic	Description	Format
`trydan_v2c_grid_power`	Grid power	Plain number (watts)
`trydan_v2c_sun_power`	Solar power	Plain number (watts)

Example messages:

text

trydan_v2c_grid_power: 3450
trydan_v2c_sun_power: 2100

Meter Modes

Each meter (grid/solar) supports two modes:

Pull Mode

v2c-any actively polls a device at regular intervals and publishes to MQTT.

Push Mode

v2c-any subscribes to MQTT topics and republishes to V2C topics.

Configuration

MQTT Connection Options

Option	Type	Required	Default	Description
`url`	`string`	Yes	-	MQTT broker URL (e.g., `mqtt://localhost:1883`)
`username`	`string`	No	-	Username for MQTT broker authentication
`password`	`string`	No	-	Password for MQTT broker authentication

Pull Feed Types

HTTP Adapter Feed

Polls a device via HTTP at regular intervals and publishes to MQTT.

yaml

grid:
  mode: pull
  feed:
    type: http-adapter
    properties:
      interval: 2000
      device: shelly-pro-em
      host: 192.168.1.100

Option	Type	Required	Default	Description
`interval`	`number`	Yes	-	Polling interval in milliseconds
`device`	`string`	Yes	-	Device type (currently: `shelly-pro-em`)
`host`	`string`	Yes	-	IP address or hostname of the device
`protocol`	`'http'` \| `'https'`	No	`'http'`	Protocol to use
`port`	`number`	No	`80`	Port number of the device
`breaker`	`BreakerOptions`	No	-	Circuit breaker configuration
`retry`	`RetryOptions`	No	-	Retry strategy configuration
`ema`	`EmaOptions`	No	-	EMA smoothing configuration

RPC MQTT Adapter Feed

Sends RPC requests over MQTT and processes responses.

yaml

grid:
  mode: pull
  feed:
    type: rpc-mqtt-adapter
    properties:
      interval: 2000
      device: shelly-pro-em
      url: mqtt://broker:1883
      topic: shellyproem/rpc
      id: shellyproem-abc123

Option	Type	Required	Default	Description
`interval`	`number`	Yes	-	Request interval in milliseconds
`device`	`string`	Yes	-	Device type (currently: `shelly-pro-em`)
`url`	`string`	Yes	-	MQTT broker URL for RPC communication
`username`	`string`	No	-	Username for MQTT broker authentication
`password`	`string`	No	-	Password for MQTT broker authentication
`topic`	`string`	Yes	-	MQTT topic to publish RPC requests
`id`	`string`	Yes	-	Device identifier used in RPC requests

Mock Feed

Publishes fixed values at regular intervals.

yaml

solar:
  mode: pull
  feed:
    type: mock
    properties:
      interval: 1000
      value:
        power: 2500

Option	Type	Required	Default	Description
`interval`	`number`	Yes	-	Publishing interval in milliseconds
`value`	`{ power: number }`	No	-	Fixed power value in watts

Off Feed (Pull)

Disables the meter.

yaml

solar:
  mode: pull
  feed:
    type: off

Push Feed Types

Bridge Feed

Subscribes to an MQTT topic and republishes to V2C topics.

yaml

grid:
  mode: push
  feed:
    type: bridge
    properties:
      url: mqtt://source-broker:1883
      device: shelly-pro-em
      topic: home/energy/grid
      keepAlive:
        type: off

Option	Type	Required	Default	Description
`url`	`string`	Yes	-	Source MQTT broker URL
`username`	`string`	No	-	Username for source broker authentication
`password`	`string`	No	-	Password for source broker authentication
`device`	`string`	Yes	-	Device type for parsing messages
`topic`	`string`	Yes	-	MQTT topic to subscribe to
`keepAlive`	`KeepAliveConfig`	Yes	-	Keep-alive configuration

Keep-Alive Configuration

In push mode, v2c-any subscribes to MQTT topics and waits for messages. To ensure fresh data, you can configure a keep-alive mechanism that periodically requests data if no messages are received.

The keep-alive timer resets whenever a message is received on the subscribed topic. If no message arrives within the interval, a request is triggered.

Off (default)HTTP-basedRPC MQTT-based

yaml

keepAlive:
  type: off

yaml

keepAlive:
  type: http-adapter
  properties:
    interval: 30000
    device: shelly-pro-em
    host: 192.168.1.101

yaml

keepAlive:
  type: rpc-mqtt-adapter
  properties:
    interval: 30000
    device: shelly-pro-em
    url: mqtt://broker:1883
    topic: shellyproem/rpc
    id: shellyproem-abc123

Off Feed (Push)

Disables the meter.

yaml

solar:
  mode: push
  feed:
    type: off

Examples

Pull Both Meters

Poll two Shelly Pro EM devices and publish to MQTT:

yaml

provider: mqtt
properties:
  url: mqtt://localhost:1883
  meters:
    grid:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 2000
          device: shelly-pro-em
          host: 192.168.1.100
    solar:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 2000
          device: shelly-pro-em
          host: 192.168.1.101

Push from Existing MQTT Infrastructure

Bridge existing MQTT topics to V2C topics:

yaml

provider: mqtt
properties:
  url: mqtt://broker.local:1883
  username: v2c-user
  password: secure-password
  meters:
    grid:
      mode: push
      feed:
        type: bridge
        properties:
          url: mqtt://solar-system.local:1883
          device: shelly-pro-em
          topic: home/energy/grid
          keepAlive:
            type: off
    solar:
      mode: push
      feed:
        type: bridge
        properties:
          url: mqtt://solar-system.local:1883
          device: shelly-pro-em
          topic: home/energy/solar
          keepAlive:
            type: off

Hybrid Pull/Push Configuration

Pull from grid meter, push from existing solar MQTT:

yaml

provider: mqtt
properties:
  url: mqtt://localhost:1883
  meters:
    grid:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 1000
          device: shelly-pro-em
          host: 192.168.1.100
    solar:
      mode: push
      feed:
        type: bridge
        properties:
          url: mqtt://solar-system.local:1883
          device: shelly-pro-em
          topic: solar/inverter/power
          keepAlive:
            type: http-adapter
            properties:
              interval: 30000
              device: shelly-pro-em
              host: 192.168.1.101

Mock Solar, Real Grid (Testing)

Simulate solar production while using real grid data:

yaml

provider: mqtt
properties:
  url: mqtt://localhost:1883
  meters:
    grid:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 2000
          device: shelly-pro-em
          host: 192.168.1.100
    solar:
      mode: pull
      feed:
        type: mock
        properties:
          interval: 1000
          value:
            power: 2500

High-Frequency with Resilience

Fast polling with circuit breaker, retry, and EMA smoothing:

yaml

provider: mqtt
properties:
  url: mqtt://localhost:1883
  meters:
    grid:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 500
          device: shelly-pro-em
          host: 192.168.1.100
          breaker:
            timeout: 300
            errorThresholdPercentage: 20
          retry:
            attempts: 3
            minTimeout: 100
            maxTimeout: 1000
          ema:
            alphaRise: 0.4
            alphaFall: 0.6
            alphaMissing: 0.1
            freshnessThreshold: 2000
    solar:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 500
          device: shelly-pro-em
          host: 192.168.1.101

Secure MQTT with TLS

yaml

provider: mqtt
properties:
  url: mqtts://secure-broker.local:8883
  username: v2c-client
  password: secure-password
  meters:
    grid:
      mode: pull
      feed:
        type: http-adapter
        properties:
          interval: 2000
          device: shelly-pro-em
          host: 192.168.1.100
          protocol: https
          port: 443
    solar:
      mode: pull
      feed:
        type: off

Complete Mock Setup

Simulate both meters for development:

yaml

provider: mqtt
properties:
  url: mqtt://localhost:1883
  meters:
    grid:
      mode: pull
      feed:
        type: mock
        properties:
          interval: 1000
          value:
            power: 3500
    solar:
      mode: pull
      feed:
        type: mock
        properties:
          interval: 1000
          value:
            power: 1800

Performance

Pull Mode Performance

Update frequency - Controlled by interval setting
Recommended intervals - 1000-5000ms for most scenarios
Network overhead - Each poll = 1 HTTP request + 1 MQTT publish
Resource usage - ~40-60 MB RAM

Push Mode Performance

Update frequency - Depends on source MQTT publishing rate
Latency - Very low (~10-50ms from source publish to V2C publish)
Network overhead - 1 MQTT subscription + 1 MQTT publish per update
Resource usage - ~30-50 MB RAM

Optimization Tips

Use push mode when possible for lower latency and better efficiency
Don't poll too aggressively - most scenarios work fine with 2-5 second intervals
Enable EMA smoothing to reduce fluctuations and publish frequency
Use circuit breaker to prevent overwhelming slow devices
Monitor MQTT broker load if handling many messages

Migration

From REST Mode

Set up an MQTT broker if not already running
Configure V2C wallbox for MQTT mode instead of Shelly REST polling
Update v2c-any configuration to use provider: 'mqtt'
Choose pull or push mode based on your data sources
Test with low intervals first, then optimize

From Shelly Direct MQTT

Keep existing Shelly devices publishing to their topics
Configure v2c-any in push mode to bridge Shelly topics to V2C topics
Update V2C wallbox to subscribe to v2c-any topics instead of Shelly topics
Optionally add resilience features (circuit breaker, retry, EMA)

Troubleshooting

V2C wallbox not receiving updates

Possible causes:

V2C wallbox not subscribed to correct topics
MQTT broker not running
Network connectivity issues

Solutions:

Verify broker is running: mosquitto_sub -h localhost -t '#' -v
Check v2c-any logs for connection errors
Ensure V2C wallbox is configured for MQTT mode
Test publishing manually: mosquitto_pub -h localhost -t trydan_v2c_grid_power -m "1000"

Connection refused to MQTT broker

Verify broker is running: docker ps or check system services
Test connection: mosquitto_sub -h broker-host -p 1883 -t test
Check firewall rules

Authentication failures

Verify credentials
Check broker logs
Use mqtts:// for TLS connections

Updates too slow in pull mode

Decrease interval value (but not too aggressively)
Consider switching to push mode if data source supports it
Check network latency to device

High CPU usage

Increase interval (e.g., from 500ms to 2000ms)
Add EMA smoothing to reduce update frequency
Monitor device response times

MQTT Mode ​

When to Use MQTT Mode ​

MQTT Topics ​

Meter Modes ​

Pull Mode ​

Push Mode ​

Configuration ​

MQTT Connection Options ​

Pull Feed Types ​

HTTP Adapter Feed ​

RPC MQTT Adapter Feed ​

Mock Feed ​

Off Feed (Pull) ​

Push Feed Types ​

Bridge Feed ​

Keep-Alive Configuration ​

Off Feed (Push) ​

Examples ​

Pull Both Meters ​

Push from Existing MQTT Infrastructure ​

Hybrid Pull/Push Configuration ​

Mock Solar, Real Grid (Testing) ​

High-Frequency with Resilience ​

Secure MQTT with TLS ​

Complete Mock Setup ​

Performance ​

Pull Mode Performance ​

Push Mode Performance ​

Optimization Tips ​

Migration ​

From REST Mode ​

From Shelly Direct MQTT ​

Troubleshooting ​

V2C wallbox not receiving updates ​

Connection refused to MQTT broker ​

Authentication failures ​

Updates too slow in pull mode ​

High CPU usage ​

MQTT Mode

When to Use MQTT Mode

MQTT Topics

Meter Modes

Pull Mode

Push Mode

Configuration

MQTT Connection Options

Pull Feed Types

HTTP Adapter Feed

RPC MQTT Adapter Feed

Mock Feed

Off Feed (Pull)

Push Feed Types

Bridge Feed

Keep-Alive Configuration

Off Feed (Push)

Examples

Pull Both Meters

Push from Existing MQTT Infrastructure

Hybrid Pull/Push Configuration

Mock Solar, Real Grid (Testing)

High-Frequency with Resilience

Secure MQTT with TLS

Complete Mock Setup

Performance

Pull Mode Performance

Push Mode Performance

Optimization Tips

Migration

From REST Mode

From Shelly Direct MQTT

Troubleshooting

V2C wallbox not receiving updates

Connection refused to MQTT broker

Authentication failures

Updates too slow in pull mode

High CPU usage