Kubota D650-B Handbuch Seite 80

0076F025
[e) Fig_ 2, Function of circuit
111
2)
At Starting
When key switch is turned to position 2, coil of starter relay
is energized and starter starts engine. GEN also starts gene­
ration for charging and LAMP is turned off.
In detail, with GEN starting, current flows to base of 01
through the route of GEN-+ Ot--+- emitter/base of Ol--+ ­
04-+ GEN, or
GEN---~ 02·--~
emitter/base of
Ol·--~ 03·--~
G EN, and therefore current also flows through 01, short­
circuiting emitter and base of 02. As a result, base current
of 02 is interrupted, 02 is turned off and accordingly cur ­
rent to LAMP is also interrupted.
(11 To relay coil of starter
[0) Fig. 3, Function of circuit
00 76F026
3) In Charging
Becuase BATT terminal voltage just after engine start is
lower than setting value (14 to 15V), or lower than zener
level of Zt, current is not supplied to base of 04 and 04 is
off, as shown in Fig. 2. 03 is on with base current which
flows th rough the route of B A
TT--~
em itter /base of
03-'~
R2
•.+ 06--~ BATT, and gate current is supplied to 8t or 82
through the route of G EN_ 01-+emitter/collector of 03--+ ­
gate/cathode of 82 __ GEN, or
GEN···~
02-·-.. emitter/col ­
lector of 03-··.. gate/cathode of 8t-·-+ GEN. When engine
speed is increased so that GEN generation voltage becomes
higher than BATT terminal voltage, 81 or 82 is turned on
and, as shown in Fig.
3,
charge current is supplied to BATT
through the route of GEN-+ 01__ BATT__ anode/cathode
of 82-+GEN, or GEN-··.. D2-··.. BATT-··.. anode/cathode of 81
...
~
GEN.
After 81 or 82 is turned on, collector current of 01 and base
current of 03 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
than the setting value, or zener level of ZI.
IE] Fig_ 4, Function of circuit
00 76F027
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, 04 is on with base current
which flows through the route of BATT-·+ emitter/base of
04-'~
ZI-'-+ D6··-+ BATT, shortcircuiting emitter and base of
03. Therefore, 03 is off with no base current and gate
current is not supplied to 81 and 82. Consequently 81 and
82 are off and BATT is not charged.
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