Shibaura ST330, Workshop Manual

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3. Constructio n
The principal components of the I C
altern ator are th e stator, the rotor, the
rectifier assembly, the I C v oltage regulator,
th e fron t bracket, the r ear brack et and th e
pulley.
The rectifier assemb ly consists of two heat
sinks, one positive and one negative, and
diode trio.
The d iode trio is used as field supply diode
and is connected to the field co il and the
termin al L on the alternato r.
The built-in I C regulator is a solid -state un it
so that it can on ly be serviced as an
assemb ly.
4. Check on the Equipment
A. C hecking the regula tor adjusting
voltage .
a. In the case o f equipment w ith out an
ammeter, connect a tes t ammeter (50A
cap acity ) at the position shown in
Fig.597Y.
596Y
597Y
b. Conn ect a voltmeter betw een the terminal B of th e alternator and the ground. In th is state,
confirm th at the reading on the vo ltmeter ind icates the battery vo ltage.
If the voltmeter reading is zero , th e wiring between the ter minal B and the battery is
faulty.
c. With th e test ammeter terminals short-circuited, start the engine.
CAU TION:
In the case of where the test ammeter is connected at the position shown in Fig.597Y, make
sure that no starting current is applied to the ammeter when the engine is started.
d. R emo ve the short circuit acro ss th e test ammeter terminals and increase the engine speed
immed iately to approx . 2 000rpm. Tak e the ammeter reading.
e. I f the ammeter reading is 5A or less, takes the voltmeter reading without changing the
engin e speed (app rox. 20 00rp m). Th e reading is th e adjusting v oltage.
f. I f th e ammeter reading is more th an 5A , continue to charg e the battery until the reading
falls to less than 5A or r ep lace the battery with a fully charged On e.
An altern ative method is to limit the charging curren t by conn ecting a 1/4 Ω (2 5W)
resistor in series w ith th e battery.