®
Advanced Water Quality Sensor
Dissolved Oxygen
8
012-14325A
A second method for a known standard with 100% dissolved oxygen saturation is to
use air-saturated water. Connect an air-stone to an air pump, and put the air-stone into
water. Allow the air-stone and air pump to run for 10 minutes to make sure that the
water is completely saturated.
For a known standard with 0% dissolved oxygen saturation, dissolve enough sodium
sulfite in 150 milliliters of distilled water such that a small amount of sodium sulfite
remains undissolved in the bottom of the beaker.
Probe Care and Maintenance
The sensing layer in the Optical Dissolved Oxygen Probe’s Sensor Cap degrades over
time due to bleaching caused by exposure to light, so the Sensor Cap must be replaced
periodically. It should also be replaced if it is cracked, scratched, or damaged. The
Sensor Cap is warranted for one year and may last much longer. The working life of a
Sensor Cap may be extended by keeping it clean and properly stored between uses.
The replacement for the Optical Dissolved Oxygen Probe Sensor Cap is model num-
ber PS-2587 (see www.pasco.com for more information).
NOTE: Do not remove the Sensor Cap except to replace it with a new
cap.
To clean the Sensor Cap, rinse it with clean water and dry it with a lint free cloth. If
necessary, use a mild detergent.
Do not use alcohols or other organic solvents
that
may deteriorate the sensing layer. When changing the Sensor Cap, rinse the clear
front surface of the nose-piece of the probe with clean water and then dry the surface
with a lint free cloth or lens tissue.
Optical Dissolved Oxygen Probe Attacking Liquids
Alcohols will remove the paint layer of the Sensor Cap.
The following will remove the paint and dye layers of the Sensor Cap and will attack
the probe housing as well:
Storage
The Optical Dissolved Oxygen Probe should not be allowed to dry out. For storage,
keep the Sensor Cap installed on the probe. Moisten the sponge that is in the end of
the Probe Cover, and place the probe in the cover so that the Sensor Cap is next to the
moist sponge.
Do
not
store the probe directly in water since that would encourage algae growth on
the probe.
Toluene
Benzene
Carbon tetrachloride
Chloroform
Methylene chloride
Acetone
Methyl ethyl ketone
Organic solvents
