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contamination (i.e. debris, grit, etc.) and cleaned with water and mild
detergent if necessary.
The same inspection should be made of the o-rings associated with
the pH or ORP sensor connector when replacing a sensor. The o-rings
should be free of dirt or debris before installing the sensor onto the
cable. If no dirt or damage to the o-rings is evident, then they should
be lightly greased with the o-ring grease provided without removing
them from their groove. However, if there is any indication of damage,
the sensor o-ring should be replaced with an identical o-ring.
To remove the sensor o-rings:
Use a small, flat-bladed screwdriver or similar blunt-tipped tool to
remove the o-ring from its groove near the sensor connector. Check
the o-ring and the groove for any excess grease or contamination. If
contamination is evident, clean the o-ring and nearby plastic parts with
lens cleaning tissue or equivalent lint-free cloth. Alcohol can be used
to clean the plastic parts, but use only water and mild detergent on the
o-ring itself. Also, inspect the o-rings for nicks and imperfections.
Using alcohol on o-rings may cause a loss of elasticity and may
promote cracking. Do not use a sharp object to remove the
o-rings. Damage to the o-ring or the groove may result.
To re-install the sensor o-rings:
Place a small amount of o-ring grease between your thumb and index
finger. (More grease is not better!) Draw the o-ring through the grease
while pressing the fingers together to place a very light covering of
grease on the o-ring. Place the o-ring into its groove ensuring it does
not twist or roll. Use the previously grease-coated finger to once again
lightly go over the surface of the o-ring.
Do not over-grease the o-rings. Excess grease may collect
particles that can compromise the seal. Excess grease can also
cause the waterproofing capabilities of the o-ring to diminish,
potentially causing leaks. If excess grease is present, remove it
using a lens cloth or lint-free cloth.
GENERAL MAINTENANCE - SENSOR PORT
It is important that the entire sensor connector end be dry when
installing, removing or replacing a sensor. This will prevent water
from entering the port. Once the sensor is removed, examine the
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connector inside the port. If any moisture is present, use compressed
air to completely dry the connector or let it air dry. If the connector
is corroded, contact YSI Technical Support or the YSI authorized
distributor where you purchased the instrument.
Remove sensors upside down (facing the ground) to help
prevent water from entering the port upon removal.
sensor MaIntenance
Typical working life for pH and ORP sensors is approximately
12-24 months depending on usage, storage and maintenance.
Proper storage and maintenance generally extends the sensor’s
working life.
SENSOR MAINTENANCE - TEMPERATURE
You must keep the temperature sensor free of build up. No additional
maintenance is required. A toothbrush can be used to scrub the
temperature sensor if needed.
SENSOR MAINTENANCE - pH AND ORP
caUtIon
: When using a cotton swab, be careful NOT to wedge
the swab between the guard and the glass sensor. If necessary,
remove cotton from the swab tip, so the cotton can reach all
parts of the sensor tip without stress. You can also use a pipe
cleaner for this operation if more convenient.
Cleaning is required whenever deposits or contaminants appear on
the glass or platinum sensor surfaces or when the sensor’s response
slows. The cleaning can be chemical and/or mechanical.
Removing the sensor from the cable may make cleaning easier. Initially,
use clean water and a soft clean cloth, lens cleaning tissue, or cotton
swab to remove all foreign material from the glass bulb or platinum
button. Then use a moistened cotton swab to carefully remove any
material that may be blocking the reference electrode junction of the
sensor.
If good pH or ORP response is not restored, perform the following
additional procedure:
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