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Model 551 pH/ORP Sensor

In some inline applications, removal of the sensor for routine cleaning or calibration becomes difficult due to conduit or wiring. The 551 quick change sensor offers a unique method of removing the sensor through through a "nut lock" adapter system. Nut Lock adapter threads directly into 1-inch NPT process connections. Bolt length options Sensor sizes up to 12 inches allow the sensor to fit through flanges and standoff pipes. The 551 sensor also includes a 3/4-inch rear connection for use in submersible applications.


Reference Axial Ion Path®

  • Patented design increases sensor life, accuracy and reliability
  • High poison resistance: reduced calibration offset error
  • Large surface reference junction eliminates clogging problems
  • Eliminates error due to fluctuating pressure
  • No exotic gel or polymer electrolytes that can be incompatible with the process
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