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trol panel located beneath the DU2 (Figure
16-4). The switch selections are labeled “A”
at the 9 o’clock position, “DAU NORM” at the
center position, and “B” at the 3 o’clock po-
sition. 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/sys-
tems displays. In the reversionary positions (A
or B), each IC-600 uses only the selected chan-
nel data from both DAUs. For example, if the
DAU reversionary switch is selected to “A”,
each IC-600 will use only channel A infor-
mation from both DAUs for display.
If either channel of either DAU should fail, a
DAU 1A, 1B, 2A, or 2B FAIL message will be
presented by the CAS. If a DAU 1A FAIL mes-
sage appears on the CAS, for example, the
pilot should move the DAU reversionary switch
to the B position. When either A or B is se-
lected, a DAU A or B REV message, as ap-
propriate, will appear on the CAS as an
advisory (Table 16-2). If both channels of a
DAU should fail, the engine instruments dis-
play for the corresponding side will be lost.
Also, any other systems information that is
processed only by that DAU will be lost.
The DAU circuit breakers are located in the IN-
STRUMENT/INDICATIONS group on each
circuit breaker panel. On the left side is DAU1
CH A and CH B, and on the right side is DAU2
CH A and CH B. DAU1 CH A and DAU2 CH
A are powered by the emer batt bus. DAU1 CH
B and DAU2 CH B are powered by the left and
right essential busses respectively.
AVIONICS MASTER
SWITCHES
Left and right avionics master switches are lo-
cated on the electrical control panel beneath
DU2 (Figure 16-5). When the avionics mas-
ter switches are selected to ON (“OFF” an-
nunciators extinguished), contactors are
energized that connect the L/R essential avion-
ics busses and L/R main avionics busses to the
respective generator busses. The associated es-
sential contactors and main bus contactors
must also be closed for the avionics busses to
be powered.
See Table 16-1 for a list of avionics equipment
that is powered from the left and right essen-
tial and main avionics busses.
If the avionics master switches are on during
ground start or for a starter-assisted airstart,
the essential avionics busses will continue to
be powered, but the contactors for the main
avionics busses will automatically depower
until the start is complete.
The AFM recommends that the avionics mas-
ter switches be turned OFF for an on ground
battery start. The essential avionics busses
must remain powered during an airstart since
they power the flight critical display units.
The emergency bus, essential busses and es-
sential avionics busses are all powered by the
emergency battery during a starter-assisted
start. The avionics equipment that must be on
during a ground start is powered from the es-
sential busses and the emergency battery bus.
L E A R J E T 4 5
P I L O T T R A I N I N G M A N U A L
16-9
FOR TRAINING PURPOSES ONLY
FlightSafety
international
ELECTRICAL
L AV
MSTR
EMER BATT
R AV
MSTR
L MAIN
L
NON-ESS
R
NON-ESS
R MAIN
L GEN
BUS-TIE
R GEN
EXT PWR
L BATT
R BATT
APU GEN
L ESS
OFF
OFF
OFF
OFF
ON
AVAIL
OFF
OFF
MAN
ON
AVAIL
OFF
OFF
OFF
OFF
R ESS
OFF
EMER
Figure 16-5. Electrical Control Panel