GE Druck ADTS 405 R/F Mk2, Инструкция по эксплуатации

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Chapter 5. TESTING AND FAULT FINDING
66 | ADTS 405 Mk2 Instruction Manual-English © 2015 General Electric Company – All rights reserved.
5.6.3 Vacuum leak check
This check confirms that the unit does not leak under vacuum conditions:
a. Press LEAK MEASURE/CONTROL to enter control mode. The display shows “Aim” in place
of “Leak Measure”.
b. Enter a Ps aim of 100 mbar by pressing: ALT/Ps, 1, 0, 0, ENTER
c. Enter a Qc aim of 0 mbar by pressing: SPEED/Qc, 0, ENTER
d. Wait the required time for temperature stabilization e.g, one minute.
e. Press LEAK MEASURE/CONTROL return to Leak Measure mode.
f. Press RATE TIMER and select [WAIT 05:00], [TIME 01:00]. Observe that the “Waiting” time
is shown on the display as it counts down, followed by the “Timing” time.
g. At the end of the “Timing” period, press ROC/Ps RATE to display the measured rate of
change of Ps (“ T ” is shown after the value indicating a timed average).
h. Check that the Ps, Qc and Pt rates are less than or equal to ±0.5 mbar/min. If the leak rate
is not achieved, allow further thermal stabilization time and re-test by pressing
RATE
TIMER and selecting [WAIT 05:00], [TIME 01:00].
i. Press CLEAR/QUIT to exit special rate time display.
5.6.4 Range Check
Using key presses based on the pressure and vacuum leak checks, control the Ps and Qc pressures
to the normal limits of operation and make sure that these are achieved. Use minimum Ps and zero
Qc and then maximum Ps and maximum Qc.
Note:
Do not exceed the maximum Pt as shown on the front panel of the unit.
Use maximum available rates of change to minimise test times.
5.6.5 Controller Stability
This check confirms the control stability:
a. Press LEAK MEASURE/CONTROL to turn the pressure controllers on. “Aim” replaces
“Leak Measure” on the display.
b. Enter a Ps aim of 510 mbar with a rate of change of 204 mbar/min. by pressing the
following:
ALT/Ps, 5, 1, 0, ENTER, ROC Ps RATE, 2, 0, 4, ENTER
c. Enter a Qc aim of 0 mbar with a rate of change of 204 mbar/min. by pressing the following:
SPEED/Qc, 0, ENTER, RATE, 2, 0, 4, ENTER
d. Press Ps and wait for the aim values to be achieved.
e. If auto-zero is enabled, wait for an auto-zero to take place.
Note:
During auto zero, the valve state changes on the mimic panel and the
display shows “Zero” in place of the airspeed aim value. The time to auto-zero
should be less than 1 minute from achieving the aim value.
f. Wait for a minimum of 20 seconds after auto-zero before proceeding.
g. Observe the measured values of Ps and Qc on the display for 1 min.
h. Check that the displayed value of Ps remains within ±0.068 mbar.
i. Check that the displayed value of Qc remains within ±0.068 mbar.
Note:
If a further auto zero takes place, allow the display to stabilize following
the auto zero before proceeding.