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IMPORTANT NOTE:
1. The altitude is the pre-set measured value when the ALT / IAS Mode is activated.
2. If the ALT / IAS Mode was activated when the device was switched off automatically
or manually, the status will be restored when the device is powered up again, and the
altitude will be displayed.
3. When the M203 displays the air speeds and the power is shut off (manually or auto-
matically), also when the Program mode is activated or the „Tare“ key is pressed, the
device will revert to displaying the altitude when the device is powered up again or the
gauging mode is selected. This function is intended to prevent errors in the measure-
ment of air speeds and is necessary, since the taring function is used at barometric
pressure in order to be able to measure the air speeds. The barometric pressure is de-
pendent upon changes in weather conditions. Resetting to altitude measurement when
the device is shut down, starting the Programming mode or pressing the taring function
all require that a new taring value be measured prior to each air-speeds measurement.
Test connection (7) – Connect the hose line between the tester and the aircraft
(Warning! In complete installations, the line must always be simultaneously connected to
the gauging nozzle and to the static via the „T“ connector. Also, one must ensure that no
additional gauging instrument (e.g. flight-hours counter) is connected to the installation
without a static connector!
SIMULTANEOUS TESTING OF THE ALTITUDE DISPLAY UNITS AND
THE IMPERMEABILITY OF THE ENTIRE INSTALLATION
Please note:
The display device is adjusted based on sea level (QNH) in the altitude display units.
1. Switch on Pump Vacuum (3)
2. Vacuum (10) – Set the „pull“ level by turning to the left. Here, it is recommended to
initially set the value „5“ as the optimum number. The value must be respectively
increased or decreased according to the length of the particular line and the power
loss after the activation of the control valve (8); for instance, when altitude changes too
quickly or when the activation limit is too low, and/or when the altimeter fails to show a
further change in altitude (stops). Activation of the controller by applying light pressure
prevents damage to the aircraft and analysis-device systems.
3. Regulator valve (8) – Triggering of test values and/or comparison of display values
between the test device and the test object. When the maximum altitude for the re-
spectively installed altimeter is attained – Standard display variants 10,000 ft (3000 m),
20,000 ft (6000 m) (max. 36,000 ft / 12,000 m), close all valves and turn them to the
right, then shut off the pump (3) and perform the impermeability test (see Meriam ope-
ration guide) Exposure time and change in accordance with the test sheet (see Meriam
operation guide) – System values?
4. If the nominal values are not attained, the system must be inspected for errors / lea-
kages. This may include the individual inspection of each installed device.
HYSTERESIS TEST
1. Air escape valve (11) – Triggering of test values and/or comparison of display values
between the test device and the test object.
TEST AT SEA LEVEL -0-
1. Switch on Pump Pressure (4).
2. Select the flow rate for the descending-value setting on the valve (9).
3. Regulator valve (8) – Warning! Triggering of test values and/or comparison of display
values between the test device and the test object. When the minimum altitude is
attained (max. -2,000 feet), shut off the pump (4) and open the air escape valve (11).
PERFORMING ALTITUDE AND AIR-SPEED INDICATOR MEASUREMENTS
1. Main switch (2) – to ON
2. Display device (1) – to ON
3. Setting the display units (see Meriam operation guide), comparison of the measured
values.
4. Test connector (7) – Hose line between the tester and altimeter or the air-speed
indicator.
5. Switch on the Vacuum Pump (3) for the altimeter and the pressure pump (4) for the
air-speed indicator.
6. Valve (10) or (9) – set the flow rate.
7. Regulator valve (8) – Triggering of test values and/or comparison of display values
between the test device and the test object. Take special precautions when performing
the air-speed indicator test!
8. Perform the impermeability test (see Meriam operation guide); shut off pump.
9. Air escape valve (11) – Triggering of test values and/or comparison of display values
between the test device and the test object.
10. Shut off pump (3) or pump (4) and open the air escape valve (11).