YSI 5200 - Manual (Page 115)

YSI Incorporated 113 5200 Recirculating System Monitor
CAUTION: When using a cotton swab with the YSI 5564 or YSI 5565, be careful NOT to wedge
the swab tip between the guard and the glass sensor. If necessary, remove cotton from the swab
tip, so that the cotton can reach all parts of the sensor tip without stress.
NOTE: If good pH and/or ORP response is not restored by the above procedure, perform the following
additional procedure:
1. Soak the sensor for 10-15 minutes in clean water containing a few drops of commercial
dishwashing liquid.
2. GENTLY clean the glass bulb and platinum button by rubbing with a cotton swab soaked in the
cleaning solution.
3. Rinse the sensor in clean water, wipe with a cotton swab saturated with clean water, and then re-
rinse with clean water.
NOTE: If good pH and/or ORP response is still not restored by the above procedure, perform the
following additional procedure:
1. Soak the sensor for 30-60 minutes in one molar (1 M) hydrochloric acid (HCl). This reagent can
be purchased from most distributors. Be sure to follow the safety instructions included with the
acid.
2. GENTLY clean the glass bulb and platinum button by rubbing with a cotton swab soaked in the
acid.
3. Rinse the sensor in clean water, wipe with a cotton swab saturated with clean water, and then re-
rinse with clean water. To be certain that all traces of the acid are removed from the sensor
crevices, soak the sensor in clean water for about an hour with occasional stirring.
NOTE: If biological contamination of the reference junction is suspected or if good response is not
restored by the above procedures, perform the following additional cleaning step:
1. Soak the sensor for approximately 1 hour in a 1 to 1 dilution of commercially available chlorine
bleach.
2. Rinse the sensor with clean water and then soak for at least 1 hour in clean water with occasional
stirring to remove residual bleach from the junction. (If possible, soak the sensor for period of
time longer than 1 hour in order to be certain that all traces of chlorine bleach are removed.) Then
re-rinse the sensor with clean water and retest.`
11.4.4 Temperature/Conductivity Sensor Cleaning
The single most important requirement for accurate and reproducible results in conductivity measurement
is a clean cell. A dirty cell will change the conductivity of a solution by contaminating it. The small
cleaning brush included in the YSI 5511 Maintenance Kit is ideal for this purpose.
To clean the conductivity cell:
1. Dip the brush in clean water and insert it into each hole 15-20 times.
2. Rinse the cell thoroughly in deionized or clean tap water.
NOTE: In the event that deposits have formed on the electrodes, perform the following additional
procedure:
1. Use a mild detergent solution in combination with the brush. Dip the brush in the solution and
insert it into each hole 15-20 times.
2. Rinse the cell thoroughly in deionized or clean tap water.