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ORAKEL pH sensors measure the online pH of any aqueous solution

pH Sensor

Key Features

  • Up to 5 years continuous operation
  • Stable and reliable
  • Suitable for all potable and process waters
  • Suitable for very low conductivity waters
  • Integral temperature compensation


The pH5 electrode has a double-junction reference to prevent contamination of the reference from sample components. This design gives the electrode a longer life compared to ordinary electrodes (up to 3 yrs). The electrode also has a hemi-shaped glass measuring surface which is more durable than the traditional bulb-shaped glass. Although they command a higher price in the market place, these sensors are more cost effective with their longer life and lower maintenance requirements, typically only needing calibration once per two or three months.

pH5 and pH6 are particularly sensitive to difficult applications such as very low ionic strength waters or high temperature applications.
pH1-3 are less expensive, more traditional combination electrodes.


Anywhere you have a requirement to measure pH is a suitable application for our pH sensors. One area the sensors excel is in the measurement of pH in very low conductivity or ultra clean water. They are also particularly suited to working in sites where reliability and ease of use are most important.

Typical applications include:

  • Remote Sites
  • Food Preparation
  • Potable Water
  • Cooling Towers
  • Paper Mills
  • Chemically Challenging Applications


Installation Options

The ORAKEL PH sensors can be installed in a variety of auxiliary flow cells and self-cleaning devices.


Quick Selection Guide


pH1 pH2 pH3 pH5 pH6
  Potable Water
Waste Water
Boiler Feedwater
  Single Open Flow Cell
Dual Open Flow Cell
Triple Open Flow Cell
Closed Flow Cell
Autoclean (flow cell)
Autoclean Immersion (dip)
Autoclean Insertion (in pipe)
At Line Tee
Welding Stub
  Connector BNC Connector Built-in cable Built-in cable Built-in cable Built-in cable
Standard Cable Length 1m 3m 6m 6m 6m
Inbuilt Temperature
Maximum Temperature 80°C 80°C 80°C 100°C 100°C
Automatic Temperature Compensation
Conductivity >100 μS/cm >100 μS/cm >100 μS/cm >100 μS/cm >300 μS/cm
Junction Single Single Double Double Double
Life Expectancy± 12-18 months 12-18 months 12-18 months 3 years 18 months
Back/Front Thread ¾” NPT ¾” NPT ¾” NPT ¾” NPT ¾” NPT

*It is recommended that the probe be submerged on the end of a pole with the cable protected by running inside the pole.


The ORAKEL can  come equipped to automatically clean itself at user defined intervals with all the benefits of no operator intervention for 6 months. The Autoflush is particularly useful in food preparation, pulp and paper, and many applications where there is likely to be a build up of solids in the sample. Autoflush is available for at line, and in line versions including dip and screw in autoclean pipe version.
See Autoflush for more information.

Product Specifications

Learn More

Find the most up to date product information and available downloads

Datasheets – EN
MMS D017 – ORAKEL control unit

Watch our Predictive Data Monitoring Video here

Read More

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