Integrated RS485 digital pH sensor with a built-in transmitter and microprocessor inside a corrosion-resistant POM housing for direct PLC connection.

Industrial wastewater treatment pH electrode monitoring continuous effluent acidity in a complex chemical process tank with high anti-interference performance.

Technical dimensions schematic of an online water quality analyzer probe showing the NPT 3/4 installation thread and customizable immersion depth.

Showing Slide 1 of 3

Digital RS485 LT3700I Industrial pH Sensor for Sewage Treatment

Our industrial RS485 digital pH sensor provides B2B suppliers with precise, anti-interference sewage treatment monitoring.

● Integrated Smart Microprocessor: Features an innovative built-in transmitter design that replaces traditional external meters, delivering direct RS485 Modbus RTU digital signal output with unmatched anti-interference capabilities in complex electrical environments.
● Heavy-Duty Industrial Construction: Engineered with a specialized, corrosion-resistant POM and glass housing combined with a rugged acid-alkali resistant (HA) sensitive glass membrane that withstands severe mechanical impacts.
● Extended Operational Lifespan: Utilizes an advanced double liquid junction design and a premium PCG polymerized gel reference electrolyte to minimize clogging, prevent electrode poisoning, and dramatically reduce maintenance intervals.
● IP68 Submersible Waterproof Rating: Built to thrive under demanding industrial conditions with a fully sealed, IP68-rated waterproof structure ensuring continuous, stable performance submerged in deep-water applications.
● Flexible Customization & Scalability: Offers excellent adaptability for system integrators with options for customized electrode insertion depths, upgradable multi-point porous ceramic junctions, and integrated direct cable links extendable up to 100 meters.

Get A Free Quote

Digital Industrial pH Sensor Features

The Digital RS485 LT3700I Industrial pH Sensor for Sewage Treatment introduces a revolutionary 2-in-1 design for global engineering procurement. By integrating a micro-transmitter into its corrosion-resistant POM housing, this online water quality analyzer eliminates costly external controllers while transmitting noise-free Modbus RTU signals directly to your PLC.

Engineered for extreme industrial processes and secondary water supply plants, it features an NPT 3/4 installation thread and customizable 90mm insertion depth. This smart pH electrode brings immense value to B2B system integrators by drastically reducing infrastructure costs, preventing sensor poisoning via a double-salt bridge, and ensuring long-term automated accuracy.

Products Categories

Feature Products

Other Instruments

Water Quality Analysis

Display Controllers & Monitors

pH / ORP

Conductivity/TDS

Dissolved Oxygen / DO

Free Chlorine

Turbidity Analysis

Sludge Concentration (MLSS)

Water Hardness

Salinity Sensor

COD Analysis

Ammonia Nitrogen NH3

MultiParameter Water Quality Meter

Water Quality Monitoring Buoy

Automobile

Coating Thickness Gauge

OBD2 scanner

Borescope

Agriculture

Soil NPK tester

Soil Conductivity meter

Soil Fertility Tester

Weather Station

Soil pH Tester

Construction

Pipe Blockage Detector

Range finder

Stud Finder

Moisture Meter

Socket Tester

Laser Distance Meter

Hardness Tester

Household

Food pH Meter

Alcohol tester

Electromagnetic Radiation Detector

Refractometer | Brix Meter

Environmental

Vibration Meter

Gauss Meter | Teslameter

Noise Meter

Hygrothermograph

Digital Manometer

Light Meter | Lux Meter

Anemometer

Stroboscopes

Get A Free Quote

Digital pH Electrode Technical Specifications

Measuring range:	0-14pH
Temperature range:	0~100°C
Pressure Rating:	0-3 Bar, 6 Bar MAX
Temp. compensation type:	NTC 22K
Slope:	95%
Membrane resistance:	<250MQ
Zero potential:	<±10 mV
Response time:	<10 s
Salt Bridge Type:	Porous ceramic core
Reference electrolyte:	PCG Polymer Gel (Standard Type)
Reference type:	dual-salt bridge reference
Installation thread:	NPT3/4″
Housing material:	POM+Glass
Insertion depth:	90mm (Other depts customizable)
PH sensitive membrane:	Acid & Alkali Resistant Sensitive Membrane (HA)
Cable connection:	integrated direct type
Power supply:	6-30VDC
Communication:	RS485, MODBUS RTU

Online Water Quality Analyzer Applications

The LT3700I digital pH sensor is specifically engineered to replace vulnerable analog setups in high-interference environments. Its unique built-in RS485 communication solves specific operational pain points across several sectors:

Specialized Application Fields:
● Industrial Process Monitoring (High-Interference Mitigation): Unlike conventional sensors whose weak millivolt analog signals are easily distorted by nearby high-power pumps, variable frequency drives (VFDs), or heavy machinery, the LT3700I processes data internally. It transmits clean, digitized Modbus RTU signals, ensuring precise, uncorrupted pH feedback in complex chemical production lines.
● Industrial Sewage Treatment (Anti-Poisoning & Longevity): Wastewater streams contain harsh chemicals and organic compounds that rapidly poison standard probes. The LT3700I features a double-salt bridge design coupled with a rugged acid-alkali resistant (HA) glass membrane. This configuration blocks aggressive contaminants from invading the reference element, drastically extending sensor lifespans in aggressive neutralization tanks.
● OEM & Equipment Matching (Cost & Space Efficiency): For water treatment skid builders and equipment integrators, space and budget are critical. Because the LT3700I integrates the transmitter right inside its POM body, it wires directly into a PLC or SCADA system. This eliminates the cost and physical panel space required for a traditional external display controller.
● Secondary Water Supply & Surface Water (Long-Distance Transmission): Monitoring decentralized water distribution stations or natural surface water requires long cable runs where analog voltage drops are fatal to data accuracy. The LT3700I supports reliable, loss-free digital signal transmission through customizable cable links extending all the way up to 100 meters.

Extra Information

Digital pH Probe Core Features & Advantages
● Direct RS485 Modbus RTU Communication: Utilizes the standard Modbus RTU protocol for direct digital signal output, ensuring strong anti-interference performance and seamless integration into industrial process control networks.
● Corrosion-Resistant POM Construction: Housing is engineered from specialized polyoxymethylene (POM) material, providing excellent chemical resistance and durability in aggressive chemical fluids and municipal effluents.
● Anti-Poisoning Double Liquid Junction: Designed with an advanced double salt bridge configuration that shields the reference element, preventing contaminant invasion and extending operational longevity.
● IP68 Certified Submersible Waterproofing: Fully encapsulated and sealed to achieve an IP68 waterproof rating, making it ideal for permanent immersion in deep aeration tanks or outdoor surface water stations.
● Heavy-Duty Sensitive Glass Membrane: Features a ruggedized acid-alkali resistant (HA) sensitive bulb that withstands severe mechanical impacts and turbulent particle flows.
● High-Precision, Fast-Response Measurement: Engineered for continuous automated testing, delivering rapid stabilization, immediate reaction times, and highly repeatable accuracy.

Customizable Online Water Quality Sensor Scalability
● Tailored Electrode Insertion Depths: The standard 90mm immersion length can be customized to match your specific tank configurations, flow cells, or pipeline dimensions.
● Upgradable Porous Ceramic Junctions: The single-point porous ceramic core can be upgraded to multi-point (double or triple-point) structures to optimize reference liquid junction stability in demanding fluids.
● Bespoke Front Electrode Shelling: Structural dimensions and specifications of the front-end sensor assembly can be modified to suit specialized mechanical fittings or existing mounting hardware.
● Long-Distance Transmission Links: The integrated direct-connect cable assembly can be safely extended up to a maximum length of 100 meters without experiencing digital transmission signal loss.