ORP (Redox) Water Quality Sensor With 4 - 20 mA Output
ORP (Redox) Water Quality Sensor With 4 - 20 mA Output

pHionics STs Series 4 - 20 mA ORP (Redox) Sensor

from $1,111.00
Configuration:

BRAND: pHionics

The pHionics STs Series ORP sensor is a 4–20 mA Redox sensor designed for continuous water quality monitoring in wastewater, industrial process control, and environmental applications. Its submersible design, isolated electronics, and low-maintenance electrode assembly make it a strong fit for PLC, SCADA, RTU, and telemetry-based monitoring systems.

Key-Features

  • 4–20 mA ORP output for PLC, SCADA, RTU, and data logger integration

  • Large double-junction electrode for reduced calibration frequency

  • Narrow 0.75" diameter for groundwater wells and tight installations

  • Fully submersible design for field and process applications

  • Stainless steel housing standard, Titanium option for harsh chemical environments

  • Secondary 0–50°C temperature signal available

  • Isolated electronics to help prevent electrical interference and ground loop issues

Applications

  • Wastewater treatment and disinfection monitoring

  • Industrial process water and chemical dosing systems

  • Aquaculture and recirculating water systems

  • Environmental monitoring (lakes, rivers, ponds, creeks, and wetlands)

  • Groundwater monitoring wells and remediation projects

  • Stormwater and surface water quality monitoring

BRAND: pHionics

The pHionics STs Series ORP sensor is a 4–20 mA Redox sensor designed for continuous water quality monitoring in wastewater, industrial process control, and environmental applications. Its submersible design, isolated electronics, and low-maintenance electrode assembly make it a strong fit for PLC, SCADA, RTU, and telemetry-based monitoring systems.

Key-Features

  • 4–20 mA ORP output for PLC, SCADA, RTU, and data logger integration

  • Large double-junction electrode for reduced calibration frequency

  • Narrow 0.75" diameter for groundwater wells and tight installations

  • Fully submersible design for field and process applications

  • Stainless steel housing standard, Titanium option for harsh chemical environments

  • Secondary 0–50°C temperature signal available

  • Isolated electronics to help prevent electrical interference and ground loop issues

Applications

  • Wastewater treatment and disinfection monitoring

  • Industrial process water and chemical dosing systems

  • Aquaculture and recirculating water systems

  • Environmental monitoring (lakes, rivers, ponds, creeks, and wetlands)

  • Groundwater monitoring wells and remediation projects

  • Stormwater and surface water quality monitoring

 
STs ORP Sensor Datasheet
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Ranges available

• -1000 to +1000 mV

• -1000 to +0 mV

• -500 to +500 mV

• +0 to +1000 mV

This ORP (Redox) water quality sensor comes standard with 25ft cable and 316 stainless steel housing, a titanium version is avaialble for harsh chemical conditions, additionally, each sensor can be purchased with any cable lenght, up to 1,000ft.

 

Why choose this ORP Sensor?

  • Designed for continuous, unattended monitoring

  • Built for harsh wastewater and industrial environments

  • Low-maintenance design reduces field visits

  • Long cable runs without signal loss (4–20 mA)

Integration & Output Compatibility

  • 4–20 mA output for PLC/SCADA

  • Compatible with RTUs and data loggers

  • Ideal for remote telemetry systems

  • Supports long-distance signal transmission

Specifications

Output 4-20 mAORP (redox)

Range-1000 to +1000 mV

Operating Temperature0-70°C

Pressure Range0-70 psi

Electrode Type Platinum sensing element, Silver/silver chloride gel-filled reference

Transmitter Type 2-wire

Automatic Temperature CompensationNoneIsolation600 VDC

Power Supply Voltage8-40 VDC

Warm-up Time2 seconds

Loop Impedance (Max)

200 Ohms at 12 VDC

800 Ohms at 24 VDC

1600 Ohms at 40 VDC

Response time95% < 20 seconds

Wetted Materials316 Stainless Steel, Delrin®, Viton™, epoxy

Length14.25 in (36.20 cm)

Width0.750 in (1.9 cm) maximum

Weight (No cable)0.50 lbs (0.227 kg)

Linearity± 4 mV

Accuracy± 4 mV*

Sensitivity± 1 mV

Stability± 2 mV

Repeatability± 10 mV

Temperature Output

Output 4-20 mA

Temperature Range0-50°C

Accuracy+/- 1°C

Linearity+/- 0.5°C

Power Supply Voltage7-40 VDC

 

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Brand: SignalFire

Eliminate the Cost and Complexity of Field Cabling: The SignalFire RANGER Node is a cellular telemetry and sensor-to-cloud platform that connects industrial and environmental field assets directly to your dashboard—no trenching or utility power required. Powered by a long-life battery, solar, or external DC source, the sensor-agnostic RANGER accepts analog, digital, pulse, HART, Modbus, and SDI-12 inputs. Data is transmitted securely over LTE-M or NB-IoT to the SignalFire Cloud or any MQTT/Sparkplug-compatible platform for real-time visualization, trending, and automated alarms.

Features

  • Sensor Agnostic: Supports analog, digital, pulse, HART, Modbus RTU, and SDI-12 signals.

  • Flexible Power: Runs on an internal field-replaceable battery (lasting up to 8 years), an optional solar panel, or external DC power.

  • Cellular Connectivity: Uses low-power LTE-M / NB-IoT networks with built-in GPS.

  • Cloud Integration: Streams natively to the SignalFire Cloud or custom MQTT/Sparkplug-compatible platforms for trending, reporting, and SMS/email alarms.

  • Remote Control: Features a controllable relay output to switch pumps, valves, or motors right from the cloud interface.

Shipping Information: This product typically ships within 10 business days. Special configurations may require additional lead time.

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