2-10
CL 601-3A/R
FOR TRAINING PURPOSES ONLY
FlightSafety Canada
L t é e
L t d .
CL-600-2B16 PILOT TRAINING MANUAL
AC Essential Bus
The AC essential bus is normally supplied
from AC bus 1. Should the voltage and/or fre-
quency of the power from AC bus 1 exceed spe-
cific tolerances, the essential power transfer
contactor switches over to allow power from
AC bus 2 to feed the AC essential bus. This ac-
tion causes a green ALTN light to illuminate
on the essential power panel. Depressing the
ALTN switchlight also causes the essential
power transfer contactor to move over and
supply the AC essential bus from AC bus 2. If
the voltage on the AC essential bus falls below
90 volts, a FAIL light on the AC essential
p ow e r p a n e l i l l u m i n a t e s ( F i g u r e 2 - 1 3 ) .
Whenever the ADG is operating, the ADG AC
emergency transfer contactor supplies power
to the AC essential bus.
ADG Bus
Whenever both main AC buses are unpowered
in flight and both IDGs are off line, the ADG
is deployed automatically. Within four seconds
of deployment, the ADG starts producing 115-
/200-volt, 3-phase, 400-Hz power. The power
is automatically routed to the AC essential
bus, hydraulic pump 3B, and the voltage and
frequency meters of the electrical control
panel. If automatic deployment fails, the ADG
may be deployed manually (Figure 2-14). the
ADG auto deploy control unit contains a test
function and an override pushbutton. If one or
more of the main AC buses have been recov-
ered, the pilot may press the POWER TXFR
OVERRIDE button to transfer the AC essen-
tial bus and hydraulic pump 3B back to their
normal power supplies. The manual deploy
assembly must be in the stowed position be-
fore the override button is pressed.
IDG
1
APU
GEN
EXT
AC
ADG
MAIN AC BUS 1
ESS AC BUS
ESS 26 VAC
AC UTIL BUS 1
AC UTIL BUS 2
GCU
GLC
1
GTC
1
GTC
2
GLC
2
AP/EP
CONT
A 23
B 23
ESS
PWR
TC
C 5
EMERG
AC TC
GCU
MONITOR
GCU
IDG
2
GCU
26 VAC 2
ADG BUS
3B
UNPOWERED
LEGEND
MAIN AC BUS 2
Figure 2-12. Total AC Power