STs Series Conductivity Sensor

Description
The pHionics STs Series™ Conductivity is a water quality sensor (sonde) designed to pair with a datalogger or RTU for real-time data capture. A narrow diameter allows the STs Series to go places others can’t while the chemical-resistant housing ensures the sensor can stay there for many years. Proprietary electrode technology provides stable measurements to reduce calibration frequency.
All parts, including the cable, are easily replaceable without tools using pHionics patented pHiConn™ System, saving frustration and money.
In addition, isolation, differential amplification, and shielding ensure a strong signal with high signal-noise ratios, all while remaining low-power.
These features make our conductivity sensor well-suited for applications such as groundwater monitoring, wastewater treatment, aquaculture, pollution monitoring, etc.

Highlighted Features
- 4-cell electrode measuring conductivity (ec), total dissolved solids (TDS), or salinity depending on scaling with datalogger or remote telemetry unit (RTU)
- Secondary 0-50°C temperature sensor
- 2-wire, 4-20 mA analog outputs compatible with many dataloggers or RTUs.
- Narrow diameter (0.75 inches or 1.9 cm) for groundwater monitoring applications
- Isolated to prevent ground loops
- Holds calibration for months at a time

Conductivity Sensor Ranges Available:
- 0-1,000 µS/cm
- 0-5,000 µS/cm
- 0-10,000 µS/cm
- 0-50,000 µS/cm
- 0-100,000 µS/cm


Quick Delivery!
Orders typically ship in 3-5 business days.

Have a question?
We have knowledgeable customer service representatives ready to help!
Business hours:
9 am to 5 pm PST – Monday through Friday

Full Features List
- 4-cell electrode to measure conductivity, TDS, or salinity depending on scaling
- Secondary 0-50°C temperature sensor
- Chemical-resistant PVDF and 316 Stainless Steel housing (Titanium optional)
- Metal housing acts as the solution ground, removing background noise caused by stray electrical currents
- Narrow diameter (0.75 inches or 1.9 cm)
- Electrode guard to reduce debris or algae buildup and protect from damage
- Fully submersible up to 70 psi
- Shielded, Kevlar®-reinforced, water-blocked polyurethane cable
- 4-20 mA signal capable of transmission up to 3 miles (with proper wire gauge)
- Automatic Temperature Compensation (2% per degree Celsius)
- Reversible Input Protection and Operation
- Built-in electrical isolation to prevent ground loops
- Signal conditioning to remove background noise
Low Maintenance
Reduce the number of site visits with the STs Series Conductivity sensor. A 4-cell electrode holds calibration for long periods of time while also preventing errors due to polarization.
In addition, the guard protects the sensing elements from algae and debris build-up, further reducing the need for calibration.
Accurate Measurements
No noise. No nonsense.
Experience the difference with our proprietary noise reduction technology.
Mounting Options
Pipe mounting
Due to their small diameter and light-weight design, pHionics STs Series™ sensors may be set up in a number of ways. They may be suspended by the Kevlar-reinforced cable down a pipe, as shown to the right, or mounted at the end of a pipe using the pHionics cmp-k compression fitting, as shown to the left and below.
Submersion
Specifications
Conductivity Sensor
Output | 4-20 mA |
Conductivity Range | 0-100,000 µS |
Electrode Type | 4-cell |
Transmitter Type | 2-wire |
Automatic Temperature Compensation | 2% per °C |
Power Supply Voltage | 8-40 VDC |
Response Time | 95% < 5 seconds |
Pressure Range | 0-70 psi |
Wetted Materials | 316 SS, Delrin®, Viton™, PVDF |
Length | 14.50 in (36.83 cm) |
Width | 0.75 in (1.90 cm) maximum |
Weight (No cable) | 0.50 lbs (0.227 kg) |
Linearity | ± 1% of full scale* |
Accuracy | ± 1% of full scale* |
Sensitivity | ± 0.05% of full scale |
*After proper calibration
Temperature Sensor
Output | 4-20 mA |
Temperature Range | 0-50°C |
Accuracy | +/- 1°C |
Linearity | +/- 0.5°C |
Power Supply Voltage | 7-40 VDC |
Cable
Cable Material | Polyurethane |
Type | 4 conductor, Kevlar® reinforced, water blocked, shielded, twisted-pair wiring |
Maximum Distance | 3 miles |
Resistance per 1000 ft (304.8 m) | 26 Ohms |
Replaceable? | Yes |
pHionics products comply fully with all applicable EU Directives to bear the CE Mark.
Delrin® and Kevlar® are registered trademarks of DuPont™. Viton™ is a trademark of Chemours.