pH Sensor InPro 3250i SG/120

pH Sensor InPro3250i/SG/120

High Performance, High Accuracy pH & ORP.The InPro 3250i SG/120 is a digital, pre-pressurized, low maintenance ISM pH & ORP sensor combined with a temperature sensor for in-line measurement in demanding applications. The 120 mm version is optimal for short installation lengths.

Highly Accurate in Extreme Conditions

The InPro 3250i SG/120 provides stable and precise readings under extreme process conditions from pH 0-14 thanks to its high-alkali pH glass membrane.

Low Maintenance and Easy-to-Use

This digital pH sensor has Intelligent Sensor Management (ISM) technology, offering predictive diagnostics to reduce maintenance and calibration.

Sterilizable and Autoclavable

This sensor provides fast and precise pH and ORP measurement, even after repeated autoclaving and sterilization cycles.

pH Sensor InPro 3250i SG/120
Specifications - pH Sensor InPro3250i/SG/120
ISM (Digital) or Analog
ISM (Digital)
pH Sensing Technology
Highly Alkali Resistant Glass Membrane for Tough Conditions (HA)
pH Range
0 – 14
Reference System
Pre-pressurized liquid electrolyte, ceramic diaphragm, Argenthal cartridge with silver-ion trap
Operating Temperature (Celsius)
0 °C - 100 °C
Operating Temperature (Farenheit)
32 °F - 212 °F
Cable Connector
Certificates & Approvals
CE; ATEX/IECEx: Ex ia IIC T6 / T5 / T4 / T3 Ga / Gb; EHEDG; FM: IS Cl. I, II, III, Div 1, GR ABCDEFG / T6; PED; METTLER TOLEDO Quality Certificate
Measurement Parameter
pH; ORP/Redox
Model Family
Operating Pressure (Bar)
0 to 4 barg
Operating Pressure (PSI)
0 to 58 psig
Process Connection
Pg 13.5 Thread
Sensor Length
120 mm
Shaft Material
Solution Ground/Redox Metal
Temperature Sensor
Hazardous Area Approvals
Hygienic/Biocompatibility Approvals
Primary Media/Application
Chemical Processes; Pharmaceutical/Life Science Production
Refillable Electroyte
Material Number(s)

Reliable, Accurate and Robust

The InPro 3250i SG/120 is designed to withstand the rigors of your production. Its pre-pressurized, maintenance-free reference system ensures high reproducibility and reliable measurement performance under diverse operating conditions.

Advanced Sensor Diagnostics with ISM

This pH sensor features a digital signal and intelligent diagnostics to help manage your maintenance. The sensor provides a clear display of its remaining lifetime, time remaining until calibration, and counts of the SIP and CIP cycles it has undergone.

Easy Validation

The InPro 3250i SG/120 is suited for chemical and pharmaceutical production. Its certification covers hazardous zone use, biocompatibility of the electrolyte, and all relevant hygiene and safety regulations.

Versatile to Meet Your Application Needs

This sensor can measure both pH and ORP (Redox), and has a built-in digital temperature sensor. It is pressure resistant up to 4 barg (58 psig), has a watertight connector, and can withstand repeated sterilization and autoclave cycles.



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pH Sensor InPro3250i/SG/120
FM Approved
Hazardous Area
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