InPro 3253i Digital pH Sensor & InPro 3253 Analog pH Sensor

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InPro 3253

InPro 3253 & InPro 3253i pH/ORP Probes

High Performance Measurements in Biopharmaceutical Applications

The InPro 3253 and InPro 3253i are pre-pressurized, liquid filled, pH and ORP sensors. These hygienic pH sensors use a steam-sterilizable pH glass membrane and automatic temperature compensation to ensure the most accurate pH measurement in biopharmaceutical production. The InPro 3253 can withstand cleaning and autoclave cycles and meets hygienic guidelines. The InPro 3253i is a digital, Intelligent Sensor Management (ISM) pH sensor with advanced diagnostics to help manage maintenance.

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pH and ORP in a Single InPro 3253 Sensor

Select models in the InPro 3253 family of pH sensors also provide an integrated ORP measurement. This allows multiple measurements from one sensor, simplifying setup and reducing costs.

Reliable & Accurate pH Measurement System

Ensuring high reproducibility and maintaining reliable measurement performance, the InPro 3253 product family provides accurate in-line measurements in demanding applications.

Sterilizable & Autoclavable for Hygienic Processes

The InPro 3253, with its steam-sterilizable pH glass membrane, is designed to withstand repeated autoclaving or sterilization cycles and still consistently provide fast and accurate measurements.

Low Maintenance in Demanding Applications

With its pre-pressurized, maintenance-free reference system combined with a temperature sensor, the InPro 3253 can be used for in-line measurements in various operating conditions.

InPro 3253i Offers ISM Advanced Diagnostics

The InPro 3253i features Intelligent Sensor Management (ISM) advanced diagnostics that provide you with the time remaining until calibration is needed to help manage your sensor maintenance.

Certified for Use in Diverse Operating Environments

Including a certification covering hazardous zone use, biocompatibility of the electrolyte, and relevant safety regulations, the InPro 3253 is designed for different uses in harsh environments.

Simplify Installation with Plug and Measure Technology

The InPro 3253i ISM pH sensor offers Plug and Measure technology, which stores calibration data in the sensor. A sensor can be calibrated away from the process, then quickly swapped-in when needed.

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What is the InPro 3253?

The InPro 3253 is a pre-pressurized, liquid filled, METTLER TOLEDO pH and ORP sensor with low maintenance requirements, made for high performance measurements in demanding applications. Designed with a steam-sterilizable pH glass membrane, the InPro 3253 can withstand the rigors of chemical and biopharmaceutical processes, including autoclaving, while complying with relevant hygiene and safety regulations. The InPro 3253i is the digital version of this sensor and offers ISM advanced predictive diagnostics to simplify both installation and calibration.

What is the difference between the InPro 3253 and InPro 3253i?

The difference between the InPro 3253 and the InPro 3253i is that the InPro 3253 uses analog technology while the InPro 3253i uses digital Intelligent Sensor Management technology (ISM). ISM advanced predictive diagnostics are featured with the InPro 3253i digital pH sensor to help manage your maintenance. The InPro 3253i provides a clear display of the sensor's lifetime remaining, the time remaining until calibration is needed, and counts of SIP and CIP cycles it has undergone.

What lengths are the InPro 3253 models available in?

The InPro 3253 and InPro 3253i pH sensors are available in a variety of lengths, optimal for different installation requirements. The InPro 3253 family of pH sensors is available in 120 mm, 225 mm, 325 mm, and 425 mm lengths.

Which model of the InPro 3253 measures ORP?

All models of the InPro 3253i digital pH sensor have the ability to measure ORP (oxidation-reduction potential, or redox) in addition to pH. Additionally, select "SG" (solution ground) models of the analog InPro 3253 can also measure ORP. The ORP is an important parameter to describe the electrochemical condition in a process. It is often used in chemical and pharmaceutical processes and is a common measurement in biotech applications as well.

What ISM features are available with InPro 3253i?

Intelligent Sensor Management technology offered with the InPro 3253i helps you manage the maintenance of your pH and ORP sensors. The InPro 3250i series offers the following ISM features:

  • Plug and Measure technology, which simplifies sensor installation after calibration.
  • ISM predictive diagnostics which help you to reduces the risk of sensor failure, while also improving process reliability. 
  • Cleaning/Sanitization Counters: Keeps track of the number of SIP, CIP or Autoclave cycles the sensor has undergone.

What transmitters are the InPro 3253 and InPro 3253i compatible with?

The InPro 3253 family of pH sensors integrate with any appropriate METTLER TOLEDO pH transmitter. These include the M80, M100M300M400 and M800 transmitters. The pH transmitter you choose depends on your environment and complete measurement requirements. The exact transmitter for your application should be selected in consultation with your local METTLER TOLEDO representative.