The RS485 Mini Soil Moisture, Temperature and EC Sensor measures soil/substrate volumetric water content, temperature, bulk EC, pore EC, and apparent dielectric permittivity, with support for RS485 Modbus RTU communication. Its IP68 resin-sealed body, durable sensing rods, low-power 3.0–28 V DC operation, reverse power protection, and built-in TVS/ESD protection make it suitable for smart agriculture, greenhouse monitoring, irrigation control, hydroponics, horticulture, and soil research applications.

This sensor is available with an RS485 Modbus RTU interface. It is compatible with the SenseCAP S2100 LoRaWAN® Data Logger, enabling low-power, long-range data transmission over LoRaWAN® networks.

Multi-Parameter Soil/Substrate Measurement: Measures volumetric water content, temperature, bulk EC, pore EC, and apparent dielectric permittivity in soil or soilless substrates. This allows users to monitor moisture status, salinity/fertilizer concentration, and substrate condition with one compact sensor.

RS485 Modbus RTU Output: Provides a digital RS485 interface with Modbus RTU protocol for stable data transmission and easy integration with data loggers, gateways, controllers, and agricultural monitoring systems. The sensor supports standard Modbus register access for reading measurement values and configuring communication parameters.

Wide Measurement Ranges: Supports 0–100% volumetric water content, -40 to 80°C substrate temperature, and 0–20 dS/m bulk EC measurement. It also provides pore EC data through Modbus registers, making it suitable for soil moisture monitoring, irrigation control, and nutrient/salinity management.

Low-Power, Wide-Voltage Operation: Operates from a 3.0–28 V DC power supply with low current consumption. The low-power design makes it suitable for battery-powered data loggers, remote field stations, and long-term agricultural monitoring deployments.

IP68 Field Protection: Built with an IP68 resin-sealed plastic body and robust epoxyencapsulation, the sensor is designed for wet, humid soil/substrate environments and long-term stable field measurement. Reverse power protection and built-in TVS/ESD protection help improve reliability during installation and protect against wiring mistakes, static discharge, and transient electrical interference.

Recommendation for S2100 Data Logger

SenseCAP S2100 Data Logger can connect to MODBUS RS485/Analog/GPIO industrial sensors including the Grow Your Idea and transmit data from sensors to the LoRaWAN network. Benefiting from its high robustness and waterproof and dustproof enclosure, the S2100 data logger can work under harsh environments such as high UV exposure, heavy rain, dusty conditions, etc. which is ideal for outdoor use. Based on LoRaWAN, it can cover a long transmission range of 2km in urban scenes and 10km in line-of-sight while keeping lower power consumption. Equipped with built-in Bluetooth and app service for OTA configuration and remote management, it enables quick setup and update. It can be battery-powered or connected to a 12V external power supply. When the 12V power supply is connected, the replaceable built-in battery is set to be used as the backup power supply.

Attention:

If you need to connect sensors or an external power supply for the S2100, please refer to the wiring diagram below. Please note that the sensor supply voltage range is 3-28 V, while the external power supply for the S2100 must be a stable 12 V supply.

Seeed also provides the SenseCAP Portal and SenseCraft to help users better manage and check data remotely.

• Product Model: S-Temp&VWC&EC-05A
• Sensor Description: RS485 Mini Soil Moisture, Temperature and EC Sensor
• Output Interface: RS485
• Protocol: Modbus-RTU
• Current Consumption:
• Measuring: 10 mA typical, 15 mA max @ 3–28 VDC
• Standby: 300 μA typical, 800 μA max @ 3–28 VDC
• Power Supply: 3.0–28 V DC
• IP Rating: IP68
• Cable Length: 2 meters
• Operating Temperature: −40 to 80°C
• Dimensions: 20 × 11 × 95 mm
• Sealing Encapsulation: Resin-packaged plastic body; robust epoxy encapsulation
• Installation: Rods fully inserted into the substrate; ensure good substrate contact
• Substrate Temperature Measurement
• Range: −40 to 80°C
• Accuracy: ±0.5°C (0–50°C), ±1.0°C (−40 to 80°C)
• Resolution: 0.1°C
• Substrate Moisture Measurement
• Volumetric Water Content (VWC) Range: 0–100% (air–water)
• Volumetric Water Content (VWC) Accuracy: ±3% (0–50%), ±5% (50–100%)
• Volumetric Water Content (VWC) Resolution: 0–50%: 0.1%; 50–100%: 0.5%
• Substrate Dielectric Constant Measurement
• Apparent Dielectric Permittivity Range: 1–81 (air–water)
• Apparent Dielectric Permittivity Accuracy: ±1 (1.00–40.00); ±3 (40.00–81.00)
• Apparent Dielectric Permittivity Resolution: 1.00–40.00: ±0.1; 40.00–81.00: ±0.5
• Substrate EC Measurement
• Range: 0–20 dS/m (0–20,000 µS/cm)
• Accuracy: ±5% (0–5 dS/m), ±10% (5–20 dS/m)
• Resolution: 0–5 dS/m: 0.01 dS/m; 5–20 dS/m: 0.1 dS/m
• Temperature Compensation: 0–50°C

Wiring Diagram:

Applications:

• Field Irrigation Management
• Greenhouse Substrate Monitoring
• Multi-Substrate Monitoring
• Research Plot Soil Balance

Documents:

• Datasheet

Certification

• HSCODE 9027899090
• USHSCODE 9027894590
• UPC
• EUHSCODE 9027109000
• COO CHINA

Package Includes:

• 1 x Mini Soil Moisture&Temp&EC Sensor