Data Acquisition Units (Daus); Reversionary Control Panel (Figure 5-14) - BOMBARDIER LEARJET 40 Pilot's Manual

DATA ACQUISITION UNITS (DAUs)

There are two dual channel Data Acquisition Units (DAUs) installed in
the tailcone equipment area of the airplane. The DAUs receive engine
and airplane systems sensor information and pass it, primarily, to the
IC-600 computers. Both channels of DAU #1 provide left engine data
and both channels of DAU #2 provide right engine data. For redundan-
cy, both channels of each DAU independently convert on-side engine
information to a common ARINC 429 data bus format and send it to
both IC-600s. The IC-600s process the information and send it to the se-
lected display unit (normally DU #2) for EICAS display. In addition to
engine information, the DAUs also collect analog data from other air-
plane systems such as fuel, hydraulic and accumulator pressure, dc
electrical power, flight control settings, cabin pressure settings/indica-
tions, and oxygen temperature/pressure.
A three-position DAU reversionary switch is provided on the rever-
sionary control panel located below DU #2 (Figure 5-14). The switch po-
sitions are labeled A, DAU NORM, and B. With the switch in DAU
NORM, both IC-600s use Channel A from the left DAU and Channel B
from the right DAU for engine/systems displays. In the reversionary
positions (A or B), each IC-600 uses only the selected channel from both
DAUs.
PM-132A
REVERSION
IC/SG NORM
1
ADC NORM
1
AHRS NORM
1
DAU NORM
A
REVERSIONARY CONTROL PANEL
Figure 5-14
2
2
2
B
Pilot's Manual
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