Embraer EMB145 Operation Manual page 1708

AIRPLANE ELECTRICAL
OPERATIONS
MANUAL
BACKUP BATTERY
A 24 V DC, 5 Ampere-hour sealed lead-acid battery provides
stabilized power for operation of the GCUs protective function, even in
case of short-circuit, when system voltage may drop near zero volts.
The Backup Battery Button, on the overhead panel controls the
backup battery. Pressing the button when the Battery 1 or 2 Selector
Knob is set to the AUTO position connects the backup battery to the
electrical system for charging. If the Backup Battery Button is
released, a caution message is displayed on the EICAS.
GENERATORS
The primary source of electrical power are the four 28 V DC,
400 Amperes, independent engine-driven brushless generators, two
installed on each engine accessory gearbox.
Each generator is automatically controlled and protected by a
dedicated Generator Control Unit (GCU), provided the Generator
Control Button on the overhead panel is pressed.
The generators will come on line when engine speed stabilizes above
56.4% N2. If a failure occurs and the Generator Line Contactor (GLC)
opens, a reset may be attempted once by releasing the associated
Generator Control Button and then pressing it again.
Anytime the Generator Line Contactor is inadvertently opened or
generator current is above 400 A, a caution message is displayed on
the EICAS. The generator voltage and current can be monitored
through the electrical page, on the MFD.
Page Code
2-05-05 7 01
REVISION 36