YEX-S1-EC-S Online Salinity Sensor for Seawater

YEX-S1-EC-S is an industrial online salinity sensor for continuous seawater and high-salinity water monitoring. It reports salinity over RS-485 Modbus RTU from a submersible IP68 probe, giving PLC, RTU and SCADA systems a direct input for seawater intake control, aquaculture supervision and brine-loop management.

Where It Fits in the YexSensor Line

The YexSensor online water quality family is organized in three tiers: the S1 standard series (cost-effective probes in an IP68 engineering-plastic housing for high-volume monitoring points), the S1 PRO stainless-steel series (316L stainless-steel housings for seawater, high-chloride and oily duty), and the S2 flagship series (dual-interface RS485 + 4–20 mA connectivity for OEM and mixed analog/digital projects). YEX-S1-EC-S sits in the S1 tier: for permanently submerged high-chloride installations where 316L construction is preferred, step up to the S1 PRO series; for dual-interface projects, see the S2 flagship series.

Core Technical Highlights

• 0–70.0 PSU full range: covers fresh water through brackish and full-strength seawater in one probe.

• Built-in temperature channel: salinity is strongly temperature-dependent, so automatic temperature compensation keeps readings comparable across sites and seasons.

• Digital RS-485 Modbus RTU: one twisted pair carries salinity and temperature to PLC, RTU, datalogger or IoT gateway with register-level diagnostics.

• IP68 submersible body: continuous immersion in tanks, basins, intake channels and fish cages; NPT 3/4 thread for pipe and flow-cell mounting.

• 12–24 V DC: compatible with solar-powered stations and standard control-cabinet supplies.

Application Scenarios

1. Seawater intake and desalination pre-treatment: trend feed-water salinity to protect membranes and control blending.

2. Marine and brackish aquaculture: keep salinity inside the tolerance band for shrimp, shellfish and finfish stocks.

3. High-salinity industrial wastewater: monitor brine loops, pickling lines and discharge streams before treatment.

4. Estuary and coastal monitoring stations: track salt-wedge movement alongside pH, DO and turbidity probes on the same Modbus bus.

Technical Specifications

Contact our engineering team for the full datasheet, temperature-compensation curve and register map before ordering.

Frequently Asked Questions

Salinity in PSU vs. conductivity in µS/cm — which should I specify?

PSU (Practical Salinity Units) is the oceanographic convention and is what regulators and aquaculture operators usually report. A conductivity sensor measures µS/cm internally and converts to PSU using a temperature-compensation algorithm. If your permit or protocol is written in PSU, specify this model; if you need raw conductivity across a wide span, use the standard YEX-S1-EC with its four switchable ranges.

Will a plastic-housing salinity probe survive permanent seawater immersion?

Engineering plastic is chemically inert in seawater and the sensing cell is isolated from the housing, so the probe performs reliably in continuous immersion. Where the mounting hardware, cable gland or process connection is also exposed to high-chloride water and you want maximum corrosion margin, the 316L stainless-steel S1 PRO series is the more conservative specification.

What information should I provide for a quotation?

Provide the salinity range you expect, water temperature range, installation method (immersion, pipe or flow cell), cable distance, power supply and Modbus integration requirements, plus quantity and destination country.

What quality assurance is provided?

Every unit passes a standardized inspection process and a 72-hour high-temperature aging test before shipment, and is backed by a one-year warranty from the date of sale. Standard delivery includes the sensor, a 5 m four-core shielded cable, an instruction manual and a certificate of conformity.

Planning a salinity monitoring project? Send us your salinity span, water temperature and control-system interface — our engineers will return a configuration proposal, Modbus register map and quotation within one business day.