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Note: Make sure to use the calibration / sample
draw adapter supplied with the hand aspirated
sample draw assembly. Do not use the battery
operated sample draw pump for this purpose.
(9) A Biosystems standard fixed flow regulator will
automatically begin flowing gas at the correct
flow rate as soon as it is fully screwed in. When
the readings stabilize, use the "+" and "-" keys
to raise or lower the readings to match the
concentration printed on the calibration cylinder
label.
(10)
When the span calibration for a particular
sensor is completed, advance to the next
channel by pushing the "Cal" button.
(11)
Make sure the correct cylinder of gas is
attached before attempting to adjust the span!
If the concentration of gas reaching the sensor
is too low to allow the instrument to be adjusted,
or if the wrong type of gas is applied to the
sensor being adjusted, a screen will be
displayed indicating that the span gas
concentration is too low.
Verify that the flow rate of the regulator is 1.0
liters per minute. Replace the cylinder, or
choose the correct sensor, and continue.
(12)
When span calibration has been completed
for all channels, press and hold the "Cal" button
down until the information screen indicates that
calibration is complete. The PhD Ultra will then
turn itself off.
Note: The “CAL” button must be held down
until the screen indicates that span calibration
has been successfully completed.
If the button is released before this message is
displayed, span values will not be updated, and
remain unchanged from the last time a span
calibration was successfully completed.
Pressing the mode button at any time cancels the
manual span calibration mode. A screen will
announce “Span Calibration Unchanged”. This will
be followed by another announcing “Begin Shut
Down, Please Wait”. The instrument will then turn
itself off.
