Yokogawa SC72 Personal Handheld Conductivity Meter - Manual (Page 45)

IM 12D03D02-01E 5-2
5. Handling of the SC72 Personal Conductivity Meter
5.2 Washing the Electrode
Dirt or stains on the electrode may have an adverse effect on the cell constant, thereby
making accurate conductivity measurement impossible. Therefore, after measurement,
rinse the electrode in clean water (for example, tap water) to remove stains. Even if
staining is not apparent, the sensor performance may have changed. If so, wash the
electrode by moving the sensor up and down in hydrochloric acid (about 0.1 mol/l) or
water with a little neutral detergent dissolved in it. [For general-purpose and pure-water
sensors: if the electrodes are difficult to clean, wipe them gently from top to bottom with
a cotton wool swab.] After cleaning the electrode, rinse it in water.
• General-purpose sensor
(The figure below shows the general-purpose sensor with the cover removed).
Remove the cover, and wipe stains off the electrodes (inner electrode and tip element)
with a cotton swab. Rinse in a cleaning solution consisting of water containing a little
neutral detergent, to remove stains from the electrode. After cleaning, wipe the electrode
element (inner and edge electrodes) with tissue paper or cotton wool.
Inner electrode (titanium) Edge electrode (titanium)
F050201.EPS
• Sensor for high-purity water measurement
Remove the reference electrode part, and wipe the electrode elements (the shaded parts
in the figure) with tissue paper or cotton wool.
Reference electrode contact
Internal electrode
Reference electrode
Cotton wool swab
F050202.EPS
* Corrosion-resistant sensors and sensors for high-conductivity measurements
Use a beaker or the like containing water, dilute hydrochloric acid, or weak neutral
detergent; move the sensor up and down so it is immersed up to the air vent, and wash
in tap water to clean out the air vent.