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(9) 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, the alarms will be
activated and a screen will be displayed
indicating that the instrument “CANT /
SPAN”. Pressing the MODE button
clears the “CANT SPAN” message and
returns the instrument to normal
operation.
C A N T
↑↓
S P A N
In the event that a “CANT SPAN”
message is displayed, verify the type and
concentration of the gas being used is
correct for the sensor being calibrated,
and replace the cylinder if necessary.
Verify that the flow rate of the regulator is
1.0 lpm. If the "CANT SPAN" message is
repeated it may indicate that the sensor
requires replacement.
(10)
When span calibration has been
completed, press and hold the "Cal"
button down until the LCD screen
indicates that calibration is complete by
showing the message “DONE”. The Ex
Chek will then turn itself off.
D O N E
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
procedure. A screen will announce “NO
SAVE” after which the instrument will turn
itself off.
N O
↑↓
S A V E
A sensor that cannot be
calibrated or is found to be out of
tolerance should be replaced
immediately. An instrument that fails
calibration may not be used until testing
with known concentration test gas
determines that accuracy has been
restored, and the instrument
is once again
fit for use.
Pressing the MODE button at any time
during the span adjustment cancels the
procedure, and causes the calibration
values in memory to remain unchanged from
the last time a span calibration adjustment
was made.