Electrolyte & Membrane Replacement for Polarographic DO Sensors

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One of the most common maintenance tasks with polarographic DO sensors is replacement of the electrolyte and membrane cap.

Polarographic Sensor Membranes

  • Put the sensor in an upright position and carefully unscrew the membrane cartridge.
  • Carefully clean the tip of the glass body with a soft tissue.
  • Check the small O-ring above the glass body. Replace if damaged.

Electrolyte Replacement

  • Use the plastic pipette of the membrane kit to pipette approximately 1 to 1.5 ml of electrolyte into the new membrane cartridge.
  • Carefully screw the cartridge onto the sensor shaft. Any spillage of electrolyte should be rinsed away with water.
  • After completion of this procedure the sensor should be reconnected to the cable and normal polarization and calibration procedures should be followed.
     
Electrolyte membrane