LK4mini I2C/1-Wire + Modbus

LK4mini is a response to the need for remote reading and storing of data from digital sensors on a server.

The device features a built-in web server (like the LK4) to view readings and configure settings through a browser. It is available in two versions: with two I2C buses, or with I2C and RS485 buses supporting Modbus RTU (this version).

Key features:

• I2C bus for connecting sensors through RJ12 connector a range of I2C sensors (list below) as well as DS18B20 on a 1-wire bus,
• RS485 bus with MODBUS protocol allows you to read pre-configured devices and prepare your own settings to read any devices using the MODBUS protocol,
• 10/100Mb Ethernet communication with PoE 802.3af power,
• Optional 5V power supply and 2.4GHz WiFi wireless transmission,
• Management via a web interface.

Main interface functionalities accessible via the web page:

• Viewing sensor data in the admin or user window with customizable dashboard layout,
• Event configuration,
• Scheduler-based action configuration,
• OLED display configuration,
• MQTT, HTTP client, and SNMP protocol configuration,
• Email notification setup,
• Access management, firmware upgrades,
• Setting local or network time (NTP).

Sensors supported by the I2C bus:

• BME280 (humidity, temperature, atmospheric pressure)
• AM2301B, AHT20, AHT25, AM2320, HTS221 (humidity, temperature)
• SPS30, APM10 (particulate matter sensor: PM1, PM2.5, PM4, PM10)
• SCD40, ACD10 (CO2 level sensor)
• 0.96-inch OLED display

Technical specifications:

• Power supply voltage: 8-58 V
• Power consumption: 0.5W 
• Power output for Modbus devices: 12V, 200mA
• PoE power: YES (802.3af) mode A, passive mode B with jumper
• Interfaces: Ethernet 10/100 Mbit/s, Wi-Fi 802.11n, RS485 MODBUS RTU,
• Operating temperature range: -20 to +85 °C
• Dimensions: 60x58x16mm
• Weight: 25 g
• DIN rail mounting: Yes (35 mm)