YSI Pro20 - Manual (Page 11)

MEMBRANE INSTALLATION
The dissolved oxygen sensor is shipped with a dry, protective red cap that will need
to be removed before using. It is very important to put a new membrane with
electrolyte solution on the sensor after removing the red cap.
Prepare the membrane solution according to the instructions on the bottle. After
mixing, allow the solution to sit for 1 hour. This will help prevent air bubbles
from later developing under the membrane. Ensure you are using the correct
electrolyte solution for the correct sensor. Galvanic sensors utilize electrolyte with
a light blue label and Polarographic sensors utilize electrolyte with a white label.
The Dissolved Oxygen sensor is supplied with cap membranes specific to the
sensor type ordered (Polarographic or Galvanic). 5913 and 5914 membrane kits
are for Galvanic sensors and the 5908 and 5909 membrane kits are for
Polarographic sensors.
Remove and discard or save the red protective cap. Thoroughly rinse the sensor tip
with distilled or deionized water. Fill the cap membrane 3⁄4 full of electrolyte
solution, then tap the cap with a finger to release any trapped air. Be careful not to
touch the membrane portion of the cap. Thread the membrane cap onto the
sensor, moderately tight. Do not use a tool. It’s typical for some of the electrolyte
solution to spill over. It is best to allow the new cap to remain on a
new sensor
overnight before trying to calibrate. For detailed instructions on changing a
membrane cap, see the Care, Maintenance, and Storage section of this manual.
BACKLIGHT
Once the instrument is on, pressing power/backlight key will turn on the
display backlight. The backlight will remain on until the key is pressed again or
after two minutes of not pressing any key on the keypad.
POWERING OFF
To turn the instrument off, press and hold the power/backlight key for three
seconds.
RUN SCREEN
Press the power/backlight
key to turn the instrument on. The instrument will
run through a self test and briefly display a splash screen with system information
before displaying the main run screen (Figure 5). The first time the Pro20 is
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