Dnepr MT10 - Checking the Generator on Motorcycle; Determining Rotative Speed of Generator; Generator Dismantling and Assembling

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Determining th e Rotative Speed of Generator Corresponding
to the Beginning of Excitation
Determine the generator speed during idling and under l oad.
In ord er to determin e the beginning of excitation during idling,
connect the generator as shown in the diagram (Fig. 37). By gra-
dually increasing the a rm ature speed, observe the vo ltm ete r read-
ings. In a serviceable generator, the armature speed must not be
greater than 1350 r.p.m. at a voltmeter reading of 6.5 V.
To determine the beginning
of excitation under load, con-
nect the generator as shown in
the diagram (Fig. 38).
By g r adua ll y increasing the
armature speed and, at the
same time, loading the g ene -
rator (by varying the rheostat
resistance) up to 10 A, obser-
ve the vollmele r readings. In
a se rvi ceab le generator, the ar -
mature speed must not be grea -
ter than 1950 r.p.m. at a volt-
Fig. 37. Dia-
gram showing
the connection
of generator for
testing
under
idling condi-
tions
f'ig. 38. D ia-
gram show-
ing the con-
nection of
generator
for
testing under
load
meter reading of 6.5 V. Fluctuations in the volt age will indi cate
that the brushes are fau.lty.
Sparking under the brushes must be weak al l o\·er the work ing
s uria ces of the brushes and h ave a bluish tint. Heavy sparking of
strawy colour and em i ssion of spa rks from under the brushes in-
dicate s th at the bru sh assembly is out of order.
Checking the Gen erator on Motorcycle
In the absence of a test be nch, the electriull characteristics may
be roughly determined on an operating engine, for which purpose
place the motorcycle on a su pport and use a portable ammeter,
class 1.5, with readings of up to 15 A, a voltmeter, class 1, with read-
ings of u.p to 15 V, and loading rheostat rated for 2 n at permi s-
sible current of up lo 20 A. In l hi s case, with the fourth speed en-
gaged, the spee dometer will read 18 km/hr, at a generator speed of
1350 r.p.m., and 27 krn/ hr, at 1950 r.p.m.
Dis
mantling and Assembling the Generator
To dismantle the generator, proceed as follows:
uncotter and then screw off the nut securing the gear, remov e
the gear and its key;
remove the g·enerator protective band and gasket after first un-
doing the coupling screw;
unscrew two coupling bolts on the rear cover;
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