Yanmar 4LHA-HTP, Operation Manual

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Chapter 9 Electrical System
4. Alternator
4LHA Serit
4-11 Alternator 12V/80A (OPTIONAL)
The alternator serves to keep the battery constantly charg-
ed. It is installed on the cylinder block by a bracket, and is
driven trom the V-pulley at the end of the crankshaft by a V-
belt.
The type of alternator used in this engine is ideal for high
speed engines with a wide range of engine speeds. It con-
tains diodes that convert AC to DC, and an IC regulator
that keep the generated voltage constant even when the
engine speed changes.
4-11.1 Features
The alternator contains a regulator using an IC, and has the
following features.
(1) The IC regulator is self-contained, and has no moving
parts (mechanical contact points). It therefore has
superior features such as freedom from vibration, no
fluctuation of voltage during use, and no need for read-
justment.
Also, it is of the over-heating compensation type and
can automatically adjust the voltage to the most
suitable level depending on the operating temperature.
(2) The regulator is integrated within the alternator to
simplify external wiring.
(3) It is an alternator designed for compactness, lightness
of weight, and high output.
(4) A newly developed U-shaped diode is used to provide
increased reliability and easier checking and
maintenance.
(5) As the alternator is to be installed on board, the follow-
ing measures are taken to provide salt-proofing.
1) The front and rear covers are salt-proofed.
2) Salt-proof paint is applied to the diode.
3) The terminal, where the inboard harness is connected
to the alternator, is nickel plated.
4-11.2 Specifications
Model of alternator
LR180-03 (HITACHI)
Model of IC regulator
TRIZ-63 (HITACHI)
Battery voltage
12V
Nominal output
12V/80A
Earth polarity
Negative earth (9)
Direction pf rotation
(viewed from pulley end)
Clockwise
Mass
5.8kg
Rated speed
5000 rpm
Operating speed
1000 ~ 9000
Speed for 13.5V
1000 or less .
Output current at 20
o
C
over 78A/5000 rpm
Regulated voltage
14.5 ±0.3V (Standard temperature
voltage gradient, -0.01/
o
C)
4-11.3 Characteristics
15
a
a
12
- - 60
3 -
100
80
o.
3
o
40
20
1 1 1
/
Regula ed voltage
r-
- c utpul curre nt for 13.5 V
/
/
/
4 6 8
Speed of alternator (rpm)
10
12
14 x to-
9-25