DISTRIBUTION
Alternating current from the inverters is dis-
tributed through the left and right AC buses.
Primary inverter output goes to the left bus,
secondary inverter output to the right bus.
These two buses are tied together by the AC
bus-tie circuit breaker, enabling either inverter
to power all AC buses. Auxiliary inverter out-
put, if installed, may be directed to either the
left or right bus.
Two step-down transformers draw 115-VAC
power from their respective 115-VAC buses,
2-15
FOR TRAINING PURPOSES ONLY
LEARJET 20 SERIES PILOT TRAINING MANUAL
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international
50 A
10 A
10 A
26 V
AC
BUS
2 A
10 A
10
A
7.5 A
2 A
10 A
10
A
26 V
AC
BUS
L AC
BUS
R AC
BUS
TRANS
PARALLELING BOX
TRANS
SECONDARY
INVERTER
AUX
INVERTER
PRIMARY
INVERTER
L PWR
BUS
R PWR
BUS
R ESS
L GEN
BUS
R GEN
BUS
BAT CHG BUS
L
GEN
R
GEN
AC VOLTS
60 A
L AC BUS
CB
R AC BUS
CB
L AUX
AC BUS CB
R AUX
AC BUS CB
AUX INV
PRI-SEC SW
L BUS
R BUS
POWER
RELAY
POWER
RELAY
POWER
RELAY
AUX INV
CB
SEC INV
SW
SEC INV
CB
PRI INV
SW
PRI INV
CB
AUX INV
ON-OFF SW
60 A
60 A
275
A
275
A
BATTERY POWER
GENERATOR POWER
LEGEND
GROUNDPOWER
PRIMARY INVERTER POWER
AUXILIARY INVERTER POWER
SECONDARY INVERTER POWER
P
S
reducing the voltage to 26 VAC. The 26 VAC
is then distributed to the installed equipment
requiring 26 VAC.
Each 115-VAC and 26-VAC bus is protected
by its respective bus circuit breaker.
The 26-VAC BUS circuit breaker applies to SNs
24-315 and subsequent, and 25-189 and subse-
quent, except 25-191. On prior SNs the trans-
formers were wired directly to the bus.
Figure 2-13. AC Power Distribution (Typical)
