Hanna Instruments HI 9829 Instruction Manual page 81

D.O. Sensor Maintenance
For a top performance probe, it is recommended to replace the membrane every
2 months and the electrolyte monthly.
Proceed as follows:
• Unscrew the membrane by turning it counterclockwise.
• Rinse a spare membrane with some electrolyte while
shaking it gently. Refill with clean electrolyte.
• Gently tap the cap over a surface to ensure that no air bubbles remain
trapped. Avoid touching the membrane.
• With the sensor facing down, completely screw the cap clockwise. Some
electrolyte will overflow.
If any deposit scales the sensor, gently brush the sensor surface with the supplied
brush, while paying attention to not damage the plastic body. Do not use the brush
on the membrane.
EC Sensor Maintenance
• After every series of measurements, rinse the probe with tap water.
• If a more thorough cleaning is required, clean the sensor with the supplied
brush or a non-abrasive detergent. Ensure that the two cylindrical holes in the
sensor are free of foreign material.
EC/Turbidity Sensor Maintenance
• After every series of measurements, rinse the probe with tap water.
• If a more thorough cleaning of the sensor is required, clean the EC cylindrical
holes in the sensor with the supplied brush or a non-abrasive detergent. En-
sure that the two cylindrical holes are free of foreign material.
• Gently remove any material that is attached to the face of the turbidity sensor
taking care to not scratch the optical windows. Use a soft cloth and non-
abrasive detergent.
• If there are cracks or scratches on the optical windows, the EC/turbidity sensor
must be replaced.
ISE Sensor Maintenance
• After measurements inspect o-ring, connector and body. Rinse ISE sensor with
tap water to remove films or other coatings.
• Shake down the sensor as you would do with a clinical thermometer to eliminate
any air bubbles.
• Soak the electrode in its corresponding 10 ppm calibration solution for at least
1/2 hour prior to calibration. Store dry in protective cap when not in use.
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