In-line pH sensors are analytical instruments designed for continuous measurement of pH in industrial processes. METTLER TOLEDO offers both analog and digital in-line pH sensors that are designed to measure accurately under harsh process conditions, in pure water and withstand high-temperature cleaning and sterilization. In-line pH probes with Intelligent Sensor Management (ISM) offer predictive diagnostics that help reduce maintenance efforts and ensure uptime for your in-line pH measurements.
In-line pH sensors have several elements that are required for them to measure the pH of a solution. The most important part of an in-line pH probe is the end which is in contact with the solution. The glass tip is a type of membrane on which a gel layer forms when the in-line pH sensor is in an aqueous solution. A similar gel layer also forms on the inside of the membrane glass. This short video explains pH and how an in-line pH probe works.
METTLER TOLEDO in-line pH probes offer a durable design suited to providing accurate pH readings in harsh chemical environments, including measurement in viscous media and at high temperatures.
In-line pH sensors with ISM technology provide advanced diagnostics to improve sensor reliability. ISM helps avoid sensor failure and ensures maintenance is only performed when needed.
Select METTLER TOLEDO in-line pH sensors are designed to withstand steam sterilization, clean-in-place processes and autoclaving, making them well suited to pharmaceutical and food production.
Plug and Measure technology in ISM in-line pH sensors allow a sensor to be calibrated away from the process in a controlled environment. This allows for fast exchange of sensors in production.
Redox measurement capabilities offered on select METTLER TOLEDO in-line pH probes allow for multiple measurements from a single sensor.
Select METTLER TOLEDO in-line pH sensors offer a pressurized reference system for continuous self-cleaning of the diaphragm to ensure constant and accurate pH measurement.
METTLER TOLEDO offers in-line pH probes designed for pure water monitoring. They can detect pH in low conductivity waters provide accurate measurement in cycle chemistry or semiconductor UPW.
This guide explains both practical and theoretical requirements in depth so that the measuring principle is understood and an accurate measurement made possible. Read more
pH systems with Intelligent Sensor Management (ISM) drastically minimize the maintenance and workload, meaning far less time spent at measurement points. Find out how to get the most from your pH sensors. Read more
This white paper explains the advantages of in-line pH measurement in the chemical industry. While chemical manufacturers have viewed in-line pH measurement in harsh environments with skepticism, this white paper addresses how advances in technology have led to three clear reasons to shift to in-line pH measurement. Read more
This guide covers good operating procedures and includes advice for maintaining in-line pH and dissolved oxygen (DO) sensors to ensure high measurement reliability at all times. Read more
The Process Analytics Catalog provides a comprehensive overview of solutions for analytical measurements in liquid process applications, pure water monitoring and gas-phase measurement. Parameters covered include pH, dissolved oxygen, dissolved CO2, conductivity, turbidity, and total organic carbon. Read more
We support and service your measurement equipment through its entire life-cycle, from installation to preventive maintenance and calibration to equipment repair.
For optimal pH measurement, it is crucial to choose the right in-line pH probe for each measurement point. The most important criteria are: process chemical composition, homogeneity, temperature and pressure, pH range and container size (length and width restrictions). The choice of in-line pH probe is of particular importance for non-aqueous, low conductivity, protein-rich and viscous samples where general-purpose glass electrodes are subject to various sources of error. The response time and accuracy of an in-line pH probe is dependent on a number of factors. Measurements at extreme pH values and temperatures or low conductivity may take longer than those of aqueous solutions at room temperature with a neutral pH value.
METTLER TOLEDO in-line pH sensors should always be stored in reference electrolyte. This allows immediate use of the in-line pH sensor when needed, and ensures a short response time. When stored dry for long periods, many in-line pH sensors must be reactivated by soaking for several hours before installation in order to get the optimal measuring results. If these measures are not sufficient, the electrode may be made functional by treating it with a special reactivation solution followed by subsequent conditioning in the reference electrolyte. Do not store an in-line pH sensor in distilled water, as this will cause the pH sensor to have a longer response time.
If an in-line pH sensor is stored at normal room temperature with its original storage cap and solution in place on the end of the electrode, it can last well over a year with no degradation in performance. If the storage solution is allowed to dry or leaks out due to storage at high temperatures, freezing or other causes, the life of the probe may be reduced significantly.
METTLER TOLEDO has a wide range of in-line pH sensors including:
