AquaSense-Sal

Four-electrode salinity, conductivity, and TDS sensor with wide dynamic range, low-polarisation cell, and RS485 / Modbus output for marine and brackish-water monitoring.

AquaSense-Sal uses an international-grade four-electrode technique to deliver higher accuracy, wider measurement range, and stronger stability than traditional two-electrode designs. The four-electrode cell resolves the polarisation issues seen at high conductivities and reduces reading errors caused by electrode fouling.

AquaSense-Sal four-electrode salinity conductivity sensor

Four-Electrode Cell

Resolves high-conductivity polarisation issues seen with two-electrode probes.

Fouling-Tolerant

Four-electrode geometry maintains accuracy as electrodes age.

Wide Range

Covers fresh water through brackish water and seawater.

RS485 + Modbus

Digital RS485 output with Modbus RTU for direct system integration.

Corrosion-Resistant

Graphite or four-electrode head resists fouling and aggressive water.

RS485 + Modbus

Digital RS485 output with Modbus RTU protocol for system integration.

Temperature Compensation

Built-in high-accuracy NTC temperature sensor.

Isolated Power

Isolated supply for stable readings in noisy electrical environments.

Continuous Monitoring

Suited to long-term online installation.

Wide Range

Covers fresh water through brackish water and brine, depending on model.

Overview

AquaSense-Sal is a four-electrode salinity / conductivity / TDS sensor built on the international-standard four-electrode measurement technique. Compared to traditional two-electrode probes, the four-electrode cell provides higher accuracy, a wider operating range, and stronger long-term stability — and it is designed to address two key weaknesses of two-electrode designs: polarisation at high conductivity, and reading errors caused by electrode fouling.

The sensor outputs RS485 with the Modbus RTU protocol and is built for online deployment on buoys, fixed stations, and process loops. Its wide dynamic range and rugged housing make it a strong fit for marine, brackish, estuarine, and saline-process applications.

Product Image

AquaSense-Sal four-electrode salinity conductivity sensor
Primary view of the AquaSense-Sal four-electrode salinity / conductivity / tds sensor.

Key Specifications

Parameter
Value
Measurement Principle
Four-electrode cell
International standard technique
Conductivity Range
0 to 200,000 µS/cm
Selectable sub-ranges
Salinity Range
0 to 80 ppt
PSS-78 algorithm
TDS Range
0 to 100,000 mg/L
Derived from conductivity
Resolution
0.1 µS/cm / 0.01 ppt / 0.1 mg/L
Output resolution
Accuracy
±1% of reading
After calibration
Temperature Range
-5 to 60 °C
Water temperature
Temperature Accuracy
±0.2 °C
Built-in NTC element
Compensation
Automatic temperature compensation
25 °C reference
Output
RS485, Modbus RTU
Default digital interface
Power Supply
DC 9-24 V, isolated
Low-noise operation
Ingress Protection
IP68
Submersible body
Pressure Rating
≤ 0.6 MPa
Deployment pressure
Cable Length
10 m standard, customisable
Submersible cable
Housing Material
POM / titanium optional
Wetted parts
View Full Specifications

Supported Parameters

Measured Parameters

Conductivity (µS/cm) Salinity (ppt / PSU) TDS (mg/L) Water Temperature

Output Options

RS485 Modbus RTU

Power Options

DC 9-24 V isolated

Environmental

-5 to 60 °C IP68 Submersible Pressure ≤ 0.6 MPa

Resources

Accessories

Calibration Solutions

Standard buffer and reference solutions for routine calibration.

Cable & Junction Box

Submersible cabling and weatherproof junction options for field wiring.

Mounting Hardware

Probe guards, flow cells, and pole or buoy mounting adapters.

Support

Wiring and protocol assistance for RS485 / Modbus RTU integration.

Integration support for sondes, buoys, fixed stations, and process panels.

Calibration, field-verification, and long-term maintenance planning.

Application support for freshwater, brackish, marine, and industrial deployments.

Ready to add reliable water-quality data?

Let's match the right probe, calibration plan, and integration to your monitoring program.

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Trusted by Experts

Used by researchers, engineers, and operators worldwide.

Built for Water

Designed for reliable freshwater, brackish, and marine service.

End-to-End Solutions

Sensors, platforms, systems, and software working together.

Global Support

Local teams and partners ready to help deploy and scale.