fluid washes into the conductivity cell.
D. pH and ORP Practices to Maintain Calibration.
1.
Keep the sensor wet with Myron L Storage Solution.
2.
Rinse away caustic solutions immediately after use.
ORP calibration solutions are not only caustic, but 5% is considered very
accurate. By using the pH zero setting (0 mV = 7 pH) for ORP and
precision electronics for detection, the Ultrameter delivers better
accuracy without calibration than a simpler instrument could using
calibration solutions.
XI.
CARE and MAINTENANCE
Ultrameters should be rinsed with clean water after use. Solvents should
be avoided. Shock damage from a fall may cause instrument failure.
A. Temperature Extremes
Solutions in excess of 160°F/71°C should not be placed in the cell cup
area; this may cause damage. The pH sensor may fracture if the
Ultrameter temperature is allowed to go below 0°C (32°F). Care should be
exercised not to exceed rated operating temperature.
Leaving the Ultrameter in a vehicle or storage shed on a hot day can
easily subject the instrument to over 150°F. This will void the warranty.
B. Battery Replacement
Dry Instrument THOROUGHLY
.
Remove the four (4) bottom
screws. Open instrument carefully; it may be necessary to rock the
bottom slightly side to side to release it from the RS-232 connector.
Carefully detach battery from circuit board. Replace with 9 volt alkaline
battery. Replace bottom, ensuring the sealing gasket is installed in the
groove of the top half of case. Re-install screws, tighten evenly and
securely.
N O T E : Because of nonvolatile EEPROM circuitry, all data stored in
memory and all calibration settings are protected even during power loss
or battery replacement.
C. pH/ORP Sensor Replacement
Order model RPR. When ordering, be sure to include the model and
serial number of your instrument to ensure receiving the proper type.
Complete installation instructions are provided with each replacement
sensor.
”
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D. Cleaning Sensors
1. Conductivity/TDS/Resistivity
The conductivity cell cup should be kept as clean as possible. Flushing
with clean water following use will prevent buildup on electrodes.
However, if very dirty samples — particularly scaling types — are allowed
to dry in the cell cup, a film will form. This film reduces accuracy. When
there are visible films of oil, dirt, or scale in the cell cup or on the
electrodes, use a foaming non-abrasive household cleaner. Rinse out
the cleaner and your Ultrameter is ready for accurate measurements.
2. pH/ORP
The unique pH/ORP sensor in your Ultrameter is a nonrefillable
combination type which features a porous liquid junction. It should not be
allowed to dry out. If it does, the sensor can sometimes be rejuvenated
by first cleaning the sensor well with a liquid spray cleaner such as
Windex™ or Fantastic™ and rinsing well. Do not scrub or wipe the
pH/ORP sensor.
Then use one of the following methods:
1.
Pour a HOT salt solution ~60°C (140°F), preferably potassium
chloride (KCI) solution — HOT tap water with table salt (NaCl)
will work fine — in the sensor well and allow to cool. Retest.
Or
2.
Pour DI water in the sensor well and allow to stand for no more
than 4 hours (longer can deplete the reference solution and
damage the glass bulb). Retest.
If neither method is successful, sensor must be replaced.
"Drifting" can be caused by a film on the pH sensor bulb. Spray a liquid
cleaner such as Windex™ or Fantastic™ into the sensor well to clean it.
The sensor bulb is very thin and delicate. Do not scrub or wipe the
pH/ORP sensor.
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Sensor
Body
pH/ORP Sensor
Top View
ORP
Electrode
pH Glass
Electrode
Reference
Junction
under Glass
pH Bulb
