CM170407AMA
When the ADTS is displaying or controlling Qc or Pt, the orange button Qc/Pt allows to
switch the display between differential Qc and absolute Pt values.
The AoA is always controlled as a differential pressure. The AoA rate can be set from the
Limits Screen (refer to SECTION 8).
4.2 OPERATIONAL MODES
4.2.1 CONTROL MODE
This is the primary mode for control of the MPS49. Air data parameter entry and all the
operational/control functions are all performed in this mode. The main display used in this
mode is the status screen (FIG 5).
While the MPS49 is in the CONTROL mode, the internal pumps are running when required
by the control system.
Entry to the CONTROL mode is by pressing the
CNTR
or
HALT
keys. The latter also
changes the commanded values to the currently simulated pressures.
NOTE
when the battery level is low, the MPS49 will automatically switch from CONTROL
to MEASUREMENT mode. It will not be possible to switch back to CONTROL mode
until the MPS49 is connected to AC power. Refer to paragraph 4.2.5 for more
details.
When the simulated values are very close to the commanded values, the MPS49 shows
“Stabilization” in the lower-left corner of the screen. The parameters of this indication can
be tuned; please refer to the Calibration and Adjustment manual for more information.
4.2.2 MEASURE MODE
The MEASURE MODE is used to place the system into the mode where only the pressure
measuring system is active and the control system is turned off. The unit under test (UUT)
becomes completely isolated from the pressure generator, and precise measurements can
be obtained when the line pressures in the UUT under test are stabilized. Whenever a
precision measurement is required, in particular when large volumes are involved, the
MEAS function should be used: all control functions are disabled and only sensor
measurement functions are active. The MEASURE mode can be accessed from all menus.
Entry to the MEASURE MODE is by pressing the
MEAS
key.
CAUTION
When the MPS49 is in MEASURE or LEAK mode of operation, the MPS49
may automatically switch to CONTROL mode if a problem is detected; for
example, a high altitude leak or a negative Qc pressure. It is possible to
permanently store the values that trigger such operation; if desired, consult
the MPS49 Calibration and Adjustment Manual.
CAUTION
The automatic protection against negative Qc pressure values is not active
while the ADTS is in Pt control mode, allowing greater versatility when the
instrument is being used in a non pitot static test application.
Different measure modes
The MPS49 supports mixed MEASURE and CONTROL modes for particular leak testing
procedures.
By pressing the
MEAS
key repeatedly, it is possible to change the state of the control
system among the MEASURE, “STATIC MEASURE” and “DYNAMIC MEASURE” modes.
•
In STATIC MEASURE mode, the altitude/Ps channel stays in MEASURE mode,
while the airspeed/Qc channel remains under control.
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