Yanmar 4LHA-HTP Operation Manual page 628

Chapter 9 Electrical System
2. Battery
2. Battery
2-1 Construction
Terminal
Battery case
The battery utilizes chemical action to convert chemical
energy to electrical energy. This engine uses a fead acid
battery which stores a fixed amount of power that can be
used when required. After use, the battery can be
recharged and used again.
As shown in the figure, a nonconductive container is filled
with dilute sulfuric acid electrolyte. Lead dioxide positive
plates and lead dioxide negative plates separated by glass
mats are stacked alternately in the electrolyte. The positive
and negative plates are connected to their respective
terminals.
Power is removed from the battery by connecting the load
across these two terminals.
When the battery is discharging, an electric current flows
from the positive plates to the negative plates. When the
battery is being charged, electric current is passed through
the battery in the opposite direction by an external power
source.
2-2 Battery capacity and battery cables
2-2.1 Battery capacity
Since the battery has a minimum capacity of 12V, 70AH, it
can be used for 100 ~ 150AH.
minimum
Battery capacity Battery capacity Battery capacity standard
cold weather
Full charged specific gravity
2-2.2 Battery cable
Wiring must be performed with the specified electric wire.
Thick, short wiring should be used to connect the battery
to the starter, (soft automotive low-voltage wire [AV wire]).
Using wire other than that specified may cause the fol-
lowing troubles:
Wire thinner than specified
Wire longer than specified
Negative plate
-Separate plate
"~-Glass mat
Positive plate
The overall lengths of the wire between the battery (+)
terminal and the starter (B) terminal, and between the bat-
tery (-) terminal and the starter (E) terminal, should be
determined according to the following table.
Note: Excessive resistance in the key switch
2-3 Inspection
The quality of the battery governs the starting performance
of the engine. Therefore the battery must be routinely in-
spected to ensure that it functions perfectly at all times.
12V — 100AH
2-3.1 Visual inspection
12V — 120AH
(1) Inspect the case for cracks, damage and electrolyte
12V — 150AH
leakage.
1.26 (2) Inspect the battery holder for tightness, corrosion, and
damage.
(3) Inspect the terminals for rusting and corrosion, and
check the cables for damage.
(4) Inspect the caps for cracking, electrolyte leakage and
clogged vent holes.
Correct any abnormal conditions found. Clean off rusted
terminals with a wire brush before reconnecting the bat-
tery cable.
9-3
r
High wiring resistance
r
Low current
Faulty starting
Battery switch
Allowable
Voltage wiring
system voltage
drop
12V 12V 0.2Vorless/100A 0.2Vorless/100A
(between the battery and start [S] terminals) can
cause improper pinion engagement. To prevent this,
follow the wiring diagram carefully.
, 4LHA Serit
Single conductor wire
Open circuit caused
by vibrations
Faulty charging
Conductor
a + b + c
cross-
allowable
section
length
area
20mm Up to 2.5m
!
(0.0311 in.') (98.43 in.)
40mm' Up to 5m
(0.062 in.') (196.87 in.)
circuit