MQTT Topic

INDEVOLT MQTT provides the following default Topic structure. Developers can customize the Topic structure according to actual deployment requirements.

Topic	Description
/test/subtopic	Device data reporting
/test/subtopic/control	Control commands
/test/subtopic/control_ack	Control execution results

1. Data Reporting

The device actively publishes operating data through the data Topic.

Topic

/test/subtopic

Subscribe

# Example: connect to a local MQTT Broker
# Replace 127.0.0.1 with your MQTT Broker address if using a remote Broker
mosquitto_sub -h 127.0.0.1 -t "/test/subtopic" -v

Data Types

A single Topic may contain multiple data types. Clients can identify the message type through the dataType field.

The Key in the JSON message corresponds to the device data point, and the Value represents the corresponding data value. For detailed data point definitions, refer to MQTT Data Points.

dataType	Description
gateway_data	Gateway information
battery_data	Battery data
inv_data	Inverter data
subdevice_info	Sub-device information data
subdevice_data	Sub-device data

Example Message

{
  "GW_SN": "xxxxxxxx",
  "dataType": "gateway_data",
  "firmwareVersion": "V140C.0B.0036",
  "rssiWifi": "-41",
  "ssidWifi": "QXTS",
  "bssidWifi": "",
  "iP": "190.160.3.167"
}

---

2. Control Command

Third-party systems can send control requests to the device through the control Topic.

Topic

/test/subtopic/control

Publish

# Example: connect to a local MQTT Broker
# Replace 127.0.0.1 with your MQTT Broker address if using a remote Broker
mosquitto_pub -h 127.0.0.1 -t "/test/subtopic/control" -m '{}'

Message Format

{
    "GW_SN": "xxxxxxxx",
    "dataType": "modbusString",
    "SN1": "xxxxxxxx",
    "dataMap": [
        {
            "groupNum": "2"
        },
        {
            "groupID": "0",
            "commandString": "010300000001840A"
        },
        {
            "groupID": "1",
            "commandString": "0110000001020000303A"
        }
    ]
}

Field Description

Field	Type	Description
GW_SN	String	Gateway serial number.
dataType	String	Message type, fixed as modbusString.
SN1	String	Target device serial number.
dataMap	Array	List of Modbus commands.

dataMap Description

The dataMap array can contain one or multiple Modbus commands. The device executes commands sequentially according to the array order.

Field	Type	Description
groupNum	String	Total number of commands.
groupID	String	Current command ID, starting from 0.
commandString	String	Modbus command in hexadecimal string format.

The content of commandString must follow the Modbus message format, including the device address, function code, register address, data, and CRC checksum.

For detailed register addresses, refer to: Modbus Register Description.

---

3. Control Response

After executing a control command, the device returns the execution result through the control response Topic.

Topic

/test/subtopic/control_ack

Subscribe

# Example: connect to a local MQTT Broker
# Replace 127.0.0.1 with your MQTT Broker address if using a remote Broker
mosquitto_sub -h 127.0.0.1 -t "/test/subtopic/control_ack" -v

Example Message

{
    "GW_SN": "xxxxxxxx",
    "dataType": "modbusString",
    "SN1": "xxxxxxxx",
    "dataMap": [
        {
            "groupNum": "2"
        },
        {
            "groupID": "0",
            "result": "success",
            "commandResponse": "018302C0F1"
        },
        {
            "groupID": "1",
            "result": "success",
            "commandResponse": "0190030C01"
        }
    ]
}

Field Description

Field	Type	Description
result	String	Command execution result
commandResponse	String	Modbus response data