DFRobot
DFRobot SEN0681 RS485 Dissolved Oxygen Sensor - Seawater
· MPN: SEN0681
This sensor is designed for monitoring dissolved oxygen in seawater and other high-salinity applications. It uses fluorescence quenching rather than a tradit...
This sensor is designed for monitoring dissolved oxygen in seawater and other high-salinity applications. It uses fluorescence quenching rather than a traditional electrochemical cell, so it does not consume oxygen during measurement and does not require electrolyte replacement.
The probe measures dissolved oxygen across a 0-20 mg/L, 0-200% saturation range and includes automatic temperature compensation via a built-in temperature sensor. It is intended for demanding marine use such as mariculture, aquaculture, coastal water quality checks and long-term environmental monitoring.
Integration is handled through an industrial RS485 interface using the standard ModBus-RTU protocol, making it suitable for PLCs, data loggers and other monitoring systems. The package includes the RS485 fluorescence dissolved oxygen sensor and a sensor cable, and DFRobot provides a product wiki for setup information.
Features:
- Optimised for saline environments: Designed for high-salinity waters with calibration and algorithms that compensate for salinity effects on dissolved oxygen measurement.
- Stable fluorescence measurement: Measures the phase difference between excited red light and reference light, avoiding oxygen consumption during measurement and eliminating electrolyte replacement.
- Robust IP68 construction: Rated for submerged marine environments with resistance to corrosion, salt and alkali, and operation up to 0.6MPa pressure.
- RS485 ModBus-RTU interface: Supports integration with PLCs, data loggers and industrial monitoring systems.
- Automatic temperature compensation: Built-in temperature sensing provides real-time data for compensated dissolved oxygen readings.
Specifications:
- Power Supply: DC10-30V
- Power Consumption: 0.2W
- Communication Interface: RS485 (Standard ModBus-RTU Protocol)
- Measurement Principle: Fluorescence
- Measuring Range: 0-20mg/L, 0-200% Saturation
- Measurement Error: ±3% FS; ±0.5°C (25°C)
- Resolution: 0.01mg/L; 0.1%; 0.1°C
- Response Time: ≤60s
- Operating Temperature: 0-40°C
- Fluorescent Film Lifespan: 1 year under normal use
- Waterproof Rating: IP68
- Pressure Resistance: 0.6MPa
- Cable Length: 5m
- Casing Material: Corrosion-Resistant Plastic
Useful for automated mariculture and aquaculture monitoring, DIY oceanographic data buoys, estuary and coastal water quality analysis, and industrial process control in saline solutions.
Jargon buster
Plain-language definitions for the technical terms used above.
- Modbus
- Modbus is an industrial communication protocol used by many meters, sensors, PLCs, and automation devices. Modbus support matters because it can make the controller easier to integrate with existing industrial equipment.
- ModBus-RTU
- ModBus-RTU is a common industrial protocol for sending sensor readings and control commands over serial links such as RS485. Knowing the sensor uses ModBus-RTU helps you choose software libraries, data loggers, or controllers that can request and interpret its readings.
- RS485
- RS485 is a robust wired serial communication standard often used in factories, farms, and buildings where cables may be long or electrically noisy. It matters because it lets this controller connect to industrial sensors, meters, and control equipment over longer distances than typical hobby serial wiring.
- Temperature compensation
- Temperature compensation means the sensor adjusts its readings to reduce errors caused by changes in water temperature. This matters for field monitoring because ponds, rivers, and tanks can vary in temperature throughout the day and across seasons.
Supplier page — dfrobot.com
Supplier Description · 145.7 KB · Click any page to view full size
