General Description; Power Distribution; Battery And External Power; Battery Servicing - Thrush Aircraft S2R-R1340 Maintenance Manual

THRUSH AICRAFT, INC - MODEL S2R-R1340

GENERAL DESCRIPTION

The aircraft 24-volt DC electrical system
is designed to provide the utmost in
reliability. One 24-volt storage battery
provides electric current for engine
starting and a reserve source of electrical
power in the event of alternator failure. A
D.C. power receptacle located on the
engine mount, left hand side of the
fuselage (see Figure 10-1 B), provides a
means for connecting external power to
the aircraft electrical system.
conserve battery life, external power
should always be used for starting
engines when temperature is below 40°F
or when performing
requiring electrical power. An alternator
powered by the engine is the primary
source of electrical power to the main
bus. The electrical system is protected
by a voltage regulator and circuit
breakers. If the alternator's output
voltage is below bus voltage, the battery
supplies the busloads.
ammeter, installed
instrument panel, indicates the discharge
or charge on the battery after the engine
is started. All electrically-operated
motors, lighting systems and other
electrical component
protected by push button thermal circuit
breakers. Switches and instruments
required for operation of the aircraft
electrical system are installed in the left
instrument panel and engine control
switch panel (Figure 10-1 E and F).

POWER DISTRIBUTION

The 24-volt D.C. electrical system can
receive electrical power from three
different sources: battery, external power
and the alternator.
operating and the alternator on the line,
electric power from the alternator is
provided through a circuit breaker to the
main bus.
10 - 2
AIRCRAFT MAINTENANCE MANUAL
To
maintenance
The D.C.
on the right
circuits are
With the engine
BATTERY AND EXTERNAL
POWER
One 24-volt storage battery provides
power to the circuit breaker through
relay(s). The relays are controlled by a
two-position (BAT
located on the engine control switch
panel (Figure 10-1F). Placing the battery
switch in the ON position closes the relay
to supply power to the right hand panel
power distribution buss from the battery
or external power receptacle.
the battery switch in the OFF position de-
energizes the battery
terminates the supply of power to the
electrical system from either of these
sources.

BATTERY SERVICING

Initial servicing of a dry charge Gill G-244
battery is as follows:
A. Remove seals (if present) from cells.
B. Fill each cell with 1.285 specific
gravity sulfuric acid to bottom of split
ring. Use only glass, rubber or
plastic materials
battery electrolyte
servicing and
clothing and rubber gloves when
handling electrolyte
personal injury.
baking soda and water to neutralize
any acid spilled on clothing, skin or
any damageable surface.
C. Sway the battery from side to side to
release any trapped air. Re-adjust
the electrolyte as necessary.
D. Let battery sit unused for one hour.
E. Check and re-adjust electrolyte level
as necessary
electrolytes to obtain proper level as
stated in procedure B.
F. Install vent plugs tightly into each
cell.
OFF-ON) switch
Placing
relay and
for containing
fluid during
wear protective
to prevent
Use a solution of
by adding more
Effective: 01/01/08