Kubota Z400-B Handbuch Seite 71

(1 )
01 72F053
0172F054
2) At Starting
When key switch is turned to position 2, coil of starter relay
is energized and starter starts engine. GEN also starts genera­
tion for charing an"d LAMP is turned off.
In detail, with GEN starting, current flows to base of
a,
through the route of G EN----+ 0, - emitter/base of
a, ­
A4 -
0
4 -
GEN, or GEN --- O
2 - - -
emitter/base of
a,
- - - A4 ._-
0
3 - ' -
GEN, and therefore current also flows
through
a"
short-Circuiting emitter and base of O
2 •
As a
result, base current of O
2
is interrupted, O
2
is turned off and
accordingly current to LAMP is also interrupted.
3) In Charging
Because BATT terminal voltage just after engine start is
lower than setting value (14 to 15V). or lower than zener
level of
Z"
current is not supplied to base of
~
and
~
is
off, as shown in Fig. 2. 0
3
is on with base current which
flows through the route of BATT"- emitter/base of 0
3 " ­
A2 -'- 0
6 ---+
BATT, and gate current is supplied to SI or
~
through the route of GEN ----+ 0
1 -
emitter/collector
of 0
3 - R3 -
gate/cathode of
~
- GEN, or GEN ..
-+
O
2
---+
emitter/collector of 0
3 " - R3 - ' -
gate/cathode of
SI --- GEN.
When engine speed is increased so that GEN generation
voltage becomes higher than BATT termina-l voltage, SI or
~
is turned on and, as shown in Fig. 3, charge current is sup­
plied to BATT through the route of GEN-
0,-
BATT
- anode/cathode of
~
- GEN, or GEN'-- O
2 ........
BATT --- anode/cathode of SI --- GEN.
After SI or
~
is turned on, collector current of 0
1
and base
current of 0
3
are supplied by GEN. not BATT.
When key switch is returned to position 1 after engine is
started, BATT is charged, if BATT terminal voltage is lower
tnan the setting value, or zener level of ZI'
0172F055
4) Over·Charge Protection
When BATT terminal voltage is higher than the setting value
or zener level of ZI, BATT is not charged by the function of
circuit as shown in Fig.4. That is,
~
is on with base current
which flows through the route of BATT --- emitter/base of
~ ..-+ Z, ..
-+
0
6 ........
BATT, shortcircuiting emitter and base
of 0
3 ,
Therefore, 0
3
is off with no base current and gate
current is not supplied to SI and
~.
Consequently SI and
~
are off and BATT is not charged.
M-61