Chapter 7. Reference
84 | ADTS 405 R/F Mk2 Instruction Manual-English
© 2017 General Electric Company – All Rights Reserved.
• Altitude correction value
c.
The set of limits used at power-up (default) can be selected using CONFIG, [LIMITS],
[DEFAULT AIRCRAFT]. The default aircraft settings can be locked using CONFIG,
[LIMITS], [LOCK AIRCRAFT] so that the operator cannot change the limits.
d.
If the selected set of limits result in the measured pressures being outside the limits,
the display shows the warning message “
OUTSIDE LIMITS GO TO GROUND
” the Ps
and Pt channels should be taken to ground or to pressures within the new selected
limits. This warning message is also displayed if the pressures measured directly after
power-up are outside the limits used at power-up.
e.
After selecting a set of limits, the altitude correction value can be changed using
SETUP
,
ALT
. The maximum Mach limit can be changed or switched off using
SETUP
,
MACH
.
7.3.4 SETUP, [OSC]
The ADTS 405 Mk2 has an oscillation facility that causes the pressure to oscillate about the
aim value at a user defined frequency and amplitude.
a.
Select oscillation channel Ps or Pt.
b.
Select [AMPL/FREQ] and enter the required amplitude and frequency.
c.
Select [START] to start oscillation.
d.
Select [STOP] to stop oscillation at the end of a half cycle.
e.
Select [FREEZE] to stop oscillation immediately.
7.3.5 SETUP, [MORE], [CONTROL], [Ps Pt DUAL]
1.
Dual channel is the normal mode of operation where both Ps (static) and Pt (pitot)
channels are connected to the unit or aircraft system under test.
2.
To test instruments such as airspeed indicators with only the Pt (pitot) channel
connected, use
SETUP
, [MORE] [CONTROL] [Ps Pt DUAL] and select [Pt].
3.
When using [Pt ONLY], the blanking cap must be removed from the Ps (static) channel
so that Ps is open to atmosphere. All the functions associated with the Ps channel are
disabled.
4.
Similarly, to test instruments such as altimeters with only Ps (static) channel
connected, select
SETUP
, [MORE] [CONTROL] [Ps Pt DUAL] and select [Ps]. All the
functions associated with the Pt channel are disabled; the blanking cap can remain
fitted to this channel.
5.
To return to dual channel operation, select
SETUP
, [MORE], [CONTROL] [Ps Pt DUAL]
and select [DUAL] and connect both channels to the unit or aircraft system under
test.
6.
The channel controllers must be in measure mode when changing [CONTROL].
7.
The Ps (static) pressure must be within ±10 mbar of the recorded QFE to select Pt
only. The control channel selection can be locked in CONFIG.
