DFRobot - Gravity: Analog Turbidity Sensor for Arduino

This Gravity turbidity sensor adds water-cloudiness sensing to Arduino projects, helping compare water samples and observe changes caused by suspended particles. Optical sensing detects changes in light transmission and scattering, providing an electrical signal for a custom display, data logger, or indicator. Selectable analog and digital output modes allow either variable readings or a simple threshold signal, with the digital threshold adjustable on the adapter. The kit includes the probe, adapter, and connecting cables, providing a practical starting point for water testing experiments, sediment demonstrations, and prototype turbidity-monitoring projects.

Figure: Gravity: Analog Turbidity Sensor for Arduino

Analog Readings for Comparing Water Samples

This turbidity sensor provides a 0-4.5V analog output for observing changes in water cloudiness through a compatible controller's analog input. Variable readings help make sample differences visible on a display or record changes during an experiment. With a response time below 500ms, this sensor supports interactive demonstrations and prototype monitoring projects where observing the changing signal is more useful than receiving only an on/off indication.

Adjustable Digital Threshold for Simple Indicators

This turbidity sensor also offers a High/Low digital output for projects that need a simple threshold-based response. The adapter potentiometer adjusts the switching threshold, allowing the trigger point to be set for the actual water samples used in the project. This mode simplifies adding a cloudiness indicator or controller-driven alert without continuously interpreting analog readings, while the selectable output keeps both approaches available in the same kit.

Probe, Adapter, and Cables Included

This turbidity sensor kit includes the optical probe, sensor adapter, probe cable, and Gravity analog sensor cable, reducing the number of separate components needed for initial assembly. Arduino examples in the Product Wiki cover both output modes, making the kit suitable for exploring variable readings and threshold detection with the same hardware. The probe's sensing section contacts the sample during testing; the top of the probe is not waterproof.

Selection Guide

Product Name

Gravity: Analog Turbidity Sensor for Arduino

UART Non-contact Optical Turbidity Sensor for Arduino

RS485 Industrial Water Quality Turbidity Sensor (0-1000 NTU)

Figure

SKU

SEN0189

SEN0554

SEN0710

Principle

Light transmittance & scattering rate change

Infrared light transmittance & scattering (non-contact)

90° light scattering method

Method

Contact type, probe immersed in liquid

Non-contact, mounted on outer container wall

Contact type, probe immersed in liquid (IP68)

Output

Analog voltage 0–4.5V / Digital high-low level

UART-TTL (9600 bps)

RS485 (ModBus-RTU)

Range

Relative turbidity (no NTU value)

Relative turbidity (no NTU value)

0–1000 NTU (resolution 0.1 NTU)

Temp. Compensation

/

/

Built-in, 0–60℃ automatic compensation

Power Supply

5V DC

5V DC

10–30V DC

Waterproof Rating

Probe tip immersible, top not waterproof

Non-contact, no waterproof requirement

IP68 fully waterproof, can be submerged long-term

Response Time

≤30s

Installation Requirements

Direct immersion, protect the top

Container diameter 40–50mm, transparent cylinder

Submersible; keep >5cm clearance around, 7cm obstacle-free below the probe

Typical Applications

Arduino education, simple experiments

Arduino education, corrosive liquids, non-contact required

Industrial wastewater, drinking water monitoring, environmental IoT

Add to Cart

• Optical sensing of water turbidity changes associated with suspended particles
• Selectable analog and digital output modes
• 0-4.5V analog output for variable readings and data logging
• High/Low digital output with potentiometer-adjustable threshold
• 5V DC operation with a maximum current of 40mA
• Response time below 500ms
• Probe, adapter, and two connecting cables included
• Arduino examples available for both output modes

• Arduino water-cloudiness indicators and data logging prototypes
• River and stream water sample comparisons
• Wastewater and effluent sample experiments
• Suspended sediment demonstrations and laboratory sample comparisons
• Educational optical water sensing projects

• Operating Voltage: 5V DC
• Operating Current: 40mA (MAX)
• Response Time:
• Insulation Resistance: 100M (Min)
• Output Method: Analog/Digital
• Analog Output: 0-4.5V
• Digital Output: High/Low-level signal (you can adjust the threshold value by adjusting the potentiometer)
• Operating Temperature: 5℃~90 ℃
• Storage Temperature: -10℃~90℃
• Weight: 30g
• Adapter Dimensions: 38mm*28mm*10mm/1.5inches *1.1inches*0.4inches

• Turbidity sensor adapter x1
• Turbidity sensor probe x1
• Turbidity sensor cable x1
• Gravity analog sensor cable x1