Xylem YSI ProDSS, User Manual

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68
Maintenance and Storage
Figure 75
pH and pH/ORP
short-term storage
Figure 76 pH and pH/ORP
long-term storage
pH - pH/ORP Sensor Storage
The pH - pH/ORP sensors are shipped with their tips in a storage bottle containing KCl. Store the pH - pH/ORP sensors
in the shipping container when not in use.
pH - pH/ORP Sensor Short-Term Storage
(Regular Use, Daily, Weekly, Biweekly)
When in regular field use, the pH-pH/ORP sensors should remain on the
bulkhead with the storage cup installed. Place a small amount of tap or
surface water, approximately 1cm, in the cup prior to storage or transport.
The probes should be kept in this water-saturated air chamber between
uses; not submerged (
Figure 75 ).
Make sure the storage cup makes a tight connection to prevent
evaporation.
pH - pH/ORP Sensor Long-Term Storage
(Longer Than 1 Month, End of Season)
When not in regular use, remove the sensor from the bulkhead and
plug the bulkhead port. Insert the sensor tip into the storage bottle and
solution that were originally supplied with the sensor (
Figure 76 ). The
storage bottle features an open cap and o-ring to form a tight seal around
the sensor tip; the solution contains KCl with potassium phthalate and a
preservative. If this original solution is not available, one can prepare a 2
M KCl solution or use pH 4 buffer as an alternative, though these solutions
should be monitored for microbial growth and replaced if growth is
apparent.
Other sensors and system components should not be stored in or
exposed to these pH buffers for long periods of time.
NOTICE:
pH - pH/ORP sensors have two specific storage
requirements:
1. Do NOT store in Zobell solution, distilled or
deionized water.
2. Do NOT let the reference electrode junction dry out.