Fluke 4322 Operator's Manual page 71

and seamlessly during every vent operation after the Controller has determined that
pressure measurement is fully vented and stable.
•
Gauge pressure measurement with intrinsically gauge pressure modules (G700K,
G10M, G70M): AutoZero tares the reading to zero gauge pressure at vent.
•
Absolute pressure measurement with intrinsically gauge pressure modules (G700K,
G10M, G70M): AutoZero tares the reading to zero gauge pressure measurement at
vent. For all subsequent measurements, the output is dynamically compensated to
indicate absolute pressure by adding the outputs of the active gauge pressure module
and the barometer module.
•
Gauge and vacuum pressure measurement with the intrinsically absolute pressure
module (A150K): AutoZero tares the reading to zero gauge pressure at vent. At all
other pressures, the output is dynamically compensated for small changes in
atmospheric pressure measured by the barometer module.
•
Absolute pressure measurement with the intrinsically absolute pressure module
(A150K): AutoZero tares the reading to zero gauge pressure measurement at vent.
For all subsequent measurements, the output is dynamically compensated to indicate
absolute pressure by adding the outputs of the active gauge pressure module and the
barometer module.
The BaroCheck feature also utilizes the stability of the barometer module to ensure
measurement performance at low pressure. The BaroCheck function compares the
outputs of the A150K pressure module and the barometer module at several points in the
atmospheric pressure range. If the pressure modules agree within the expected tolerance,
the BaroCheck function will compensate the output of the A150K pressure module by the
difference. If the pressure modules do not agree within the expected tolerance, one of the
components may be failing or exceeding measurement tolerance, so compensation will
not be applied and the Controller will alert the user to a potential measurement issue.
The BaroCheck function is recommended to be run at least once every 30 days. The
Controller keeps track of when BaroCheck has been run, and will indicate if 30 days has
been exceeded with a "BaroChk" indication in the top left of the Main menu.
The BaroCheck function can be performed by selecting "BaroCheck" under the
Calibration tab in the Settings Menu while in Advanced Mode. If the user selects to run a
test procedure or perform a calibration while the Controller is displaying the BaroCheck
indication, the operator will be prompted to first perform the BaroCheck routine. If more
than 45 days has passed since the last successful BaroCheck routine, the Controller will
force BaroCheck to be performed before proceeding with a test procedure or calibration.
BaroCheck is performed automatically once initiated. When running the BaroCheck
function, the Controller will prompt the operator to cap the test port and acknowledge to
proceed. The controller will indicate that BaroCheck is in progress for approximately 5 to
10 minutes as it automatically sets several test points and verifies measurement. The
Controller will beep three times at the conclusion of the test to alert the user that the
function is complete. If BaroCheck detects damage or a suspected an out of tolerance
condition, the Controller will notify the user to perform the BaroCheck function again or
to check calibration of the A150K and barometer modules.
Controller Operation
Measurement Settings and Limits
3
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