MSA Ultima X Series Installation & Maintenance Instructions Manual page 122

Calibration initiated screen
Once a calibration selection function is selected, the command is sent
to the device. A status message is then returned to indicate the
progress. The first status message should indicate that the calibration
sequence has started. This screen also shows the sensor value, units
and type information. No action is required for this screen as it is only a
five-second information screen and will advance automatically. The user
may abort the process at this time. See FIGURE D-10 for a view of this
screen. The red and green LEDs on the main board blink momentarily
to indicate the device has begun the procedure.
Selection Confirmation Screen
After the initiating screen displays for five seconds, a second
information screen displays. This screen also displays for five seconds
and provides confirmation of the current calibration selection. No action
is required at this screen, but the user may press the ABORT button to
stop the process. See FIGURE D-11 for a view of this screen.
Sensor Zero Countdown screen
Once the information screens are displayed, the device should start
sending back a status byte to indicate the progress of the calibration.
The first status message should be the 30-second device countdown
message prompting the user to start applying Zero gas if necessary.
This screen also displays the current gas reading from the sensor. (This
screen is skipped for the Oxygen sensor, as it uses an electronic Zero).
This message displays during the 30-second countdown; the user can
abort the process at any time. See FIGURE D-12 for a view of this
screen message. The red LED is OFF and the green LED is blinking on
the main circuit board to indicate the start of the Zero procedure.
Zero Adjustment screen
After the 30-second countdown screen (or the selection confirmation
screen for an Oxygen sensor), the device should send back a status
message indicating that the device is attempting to adjust the internal
calibration. The user is prompted to apply Zero gas (or room air) at this
time. The device waits for a stable reading to occur and then saves the
zero calibration data automatically. The user can abort the process at
any time by selecting the ABORT button. See FIGURE D-13 for a view
of this screen.
Sensor Span countdown screen
After successful completion of the sensor Zero procedure, the device
automatically steps to the Span routine and displays an information
screen indicating the Span procedure has started. This is a 30-second
D-38