EV-Meter Client

A Python client library for EV-Meter electric vehicle chargers that communicate via MQTT using the BLEWIFI protocol.

Features

• Async MQTT client for EV-Meter chargers
• Binary protocol parsing for BLEWIFI messages
• Comprehensive data models with 25+ fields
• Real-time monitoring of charging sessions
• 3-phase electrical measurements (voltage, current, power)
• Energy tracking (session and lifetime totals)
• Diagnostic information (warnings, errors, WiFi status)

Installation

pip install evmeter-client

Quick Start

import asyncio
from evmeter_client import EVMeterClient, EVMeterConfig

async def main():
    # Configure with your charger details
    config = EVMeterConfig(
        user_id="your-user-id-hex-string"
    )
    
    # Create client and connect
    client = EVMeterClient(config)
    await client.connect()
    
    try:
        # Get charger status
        status = await client.get_charger_status("YOUR_CHARGER_ID")
        print(f"Charger Status: {status.charger_state}")
        print(f"EV Status: {status.ev_status}")
        print(f"Power: {status.power_kw} kW")
        
        # Get detailed metrics
        metrics = await client.get_charger_metrics("YOUR_CHARGER_ID")
        print(f"Session Energy: {metrics.session_energy_kwh} kWh")
        print(f"Voltage L1: {metrics.voltage_l1} V")
        print(f"Current L1: {metrics.current_l1} A")
        
    finally:
        await client.disconnect()

# Run the example
asyncio.run(main())

Configuration

The library connects to the EV-Meter MQTT broker with hardcoded settings:

config = EVMeterConfig(
    user_id="your-hex-user-id",  # Required: Your unique user ID
    mqtt_host="mqtt.evmeter.com",  # Fixed
    mqtt_port=1883,  # Fixed
    mqtt_username="deviceEV",  # Fixed
    mqtt_password="ng4GycjMmuvpSJU6"  # Fixed
)

Only the user_id needs to be configured - get this from your EV-Meter app or MQTT logs.

Data Models

ChargerStatus

• charger_state: Current charger state (IDLE, CHARGING, ERROR, etc.)
• ev_status: EV connection status (NOT_CONNECTED, CONNECTED, WANTS_TO_CHARGE, etc.)
• charging_state: Detailed charging state (1_PHASE, 3_PHASE, WAITING, etc.)
• power_kw: Real-time power consumption
• session_energy_kwh: Current session energy
• total_energy_kwh: Lifetime energy total
• warnings: Warning count
• errors: Error count

ChargerMetrics

• 3-Phase Electrical: Individual and average voltage/current for all phases
• Energy: Session and total energy with precise measurements
• Configuration: Set current limit, circuit breaker rating
• System: Temperature, WiFi RSSI, firmware versions
• Diagnostics: EVSE status, ping latency, peer serial number

Protocol

The library implements the BLEWIFI protocol used by EV-Meter chargers:

• Command Topic: /BLEWIFI/Chargers/{charger_id}
• Response Topic: /BLEWIFI/users/{user_id}
• Binary Payloads: Custom binary format with comprehensive working info

MQTT Monitoring Utility

The package includes a command-line utility for monitoring all MQTT traffic on the EV-Meter broker:

# After installing the package
evmeter-monitor

This utility will:

• Connect to the EV-Meter MQTT broker
• Subscribe to all topics (# wildcard)
• Display all messages with timestamps
• Attempt to parse payloads and show both raw and parsed data
• Show parsing failures for non-BLEWIFI messages

Example output:

[2025-11-08 13:06:29.608] Topic: /device/state/0000000000208348
Raw payload: Text: left
✗ Parsing failed: fromhex() argument must be str, not bytes
------------------------------------------------------------

[2025-11-08 13:06:30.123] Topic: /BLEWIFI/users/1234567890abcdef
Raw payload: Hex: aa 55 17 00 01 02 03 04 05 06 07 08 09 0a 0b 0c (24 bytes)
✓ Parsing succeeded!
Parsed data:
{
  "charger_state": "CHARGING",
  "ev_status": "CONNECTED",
  "power_kw": 7.2,
  "session_energy_kwh": 12.5
}
------------------------------------------------------------

You can also run the standalone script:

python mqtt_monitor.py

Error Handling

from evmeter_client.exceptions import EVMeterError, EVMeterTimeoutError

try:
    status = await client.get_charger_status("CHARGER_ID")
except EVMeterTimeoutError:
    print("Charger didn't respond in time")
except EVMeterError as e:
    print(f"EV-Meter error: {e}")

Development

# Clone the repository
git clone https://github.com/yourusername/evmeter-client.git
cd evmeter-client

# Install development dependencies
pip install -e ".[dev]"

# Run tests
pytest

# Format code
black .
ruff check .

Home Assistant Integration

This library is used by the EV-Meter Home Assistant integration to provide comprehensive monitoring of EV-Meter chargers in Home Assistant.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Changelog

v1.0.0

• Initial release
• Full BLEWIFI protocol support
• Comprehensive data models
• Async MQTT client
• Real-time monitoring capabilities