Load Distribution - Honda HondaJet HA-420 Pilots Operating Manual

Honda Aircraft Company
HA-420 SYSTEMS
POM DESCRIPTION
The BATTERY switch, when selected ON, connects the batteries to
BATT BUS 1 and BATT BUS 2. Both batteries are used in parallel to
provide power when both generators are not online.
External Power
The external power can supply 28 VDC to the airplane during ground
operations. External power also assists Battery 2 during the first engine
start. The second start is assisted by the generator on the operating
engine.

LOAD DISTRIBUTION

Solid-state relays (SSR) located in each PDU provide overcurrent
protection and control sequencing of loads during engine start, and
perform load shed of high power loads in the event that one or both
generators go off-line. Tripped SSRs can be reset from the CDU Power
page which also shows a list of tripped SSRs.
Other high power loads such as the Ground Cooling Fan (GCF) and the
Air Conditioner are powered directly, with discrete signals provided to
their respective controllers to enable/disable the associated load
depending on power source availability.
Power to cabin system loads is sourced through two Cabin Bus (A and
B) SSRs. Selecting the CABIN POWER switch to OFF commands both
SSRs open.
Fuses installed in the PDUs are used to protect individual buses and
wiring to high power loads.
HJ1-29000-005-001
October 30, 2016 1-174
FOR TRAINING PURPOSES ONLY