m e n t is just before voltage starts
of the varidrive assembly by turn-
to rise the second time (observe dc
i n g the speed control handle (24)
voltmeter (4)).
c o u n t e r c l o c k w i s e until 2,000 rpm
are indicated on the tachometer in-
Caution: Adjust to the peak
d i c a t o r meter (3).
point of 32 volts or less. If voltage
tends to go higher, screw coil core
r e g u l a t o r voltage to 28.0 plus or
( 8 , fig. 58) out and repeat, ( d )
minus 0.1 volt by adjusting the 5-
a b o v e , until the peak voltage is
o h m adjustable resistor (fig. 56)
equal to or less than 32 volts.
b y the voltage adjustments (fig.
(e)
57) (access from the top or side of
below, has a locking screw (14, fig.
which must be loosened before
and
Operate under
the regulator).
tightened after each adjustment of
the
these conditions for about 15 min-
coil core.
u t e s or more (depending on ambi-
(e) If the voltage is stable at 29.5 when
ent temperature conditions) to
making adjustments in (d) a b o v e ,
warm up the regulator.
continue with procedures in (6) be-
(i) Check occasionally with the elec-
low. If not, adjust to 29.5 volts by
trical headset, (f) above, to see that
screwing the coil core (8, fig. 58)
t h e hum of the carbon pile flutter
o u t to raise the voltage and in to
d o e s not stop. Check the carbon
lower the voltage.
pile flutter by shock testing: place
the starter test load disconnect
regulator is in proper adjustment, the
switch (15) to "ON" then to "OFF"
core flush paint marks on the coil pot end
positions and listen in the electrical
plate (9, fig. 58) and on the coil core (8,
headset for the hum to not stop.
facturer during assembly) must aline
Note. If carbon pile stops humming,
within one-eighth of a turn clockwise and
adjust carbon pile, (e) (4) (a) t h r o u g h ( g )
within one-fourth of a turn counterclock-
a b o v e , a n d r e p e a t (f) (3) (a) t h r o u g h ( c )
wise, measured from the stationary mark.
a b o v e . Continue with adjustments in (4)
If the core mark is more than one-eighth
below.
of a turn clockwise, disassemble the regu-
(4) Preliminary voltage adjustment.
lator and remove shims (one shim is
(a) Place the battery on-off switch
equivalent to about one-eighth of a turn).
If the core mark is more than one-fourth
( 2 2 ) in the "OFF" position and
o f a turn counterclockwise, disassemble
turn the speed control handle (24)
r e g u l a t o r and add shims.
s l o w l y clockwise until 1,000 rpm
Caution: Never leave less than
are indicated on the tachometer in-
two shims in the regulator. When
d i c a t o r meter (3).
t h i s condition arises, replace the
(b) Adjust the 5-ohm adjustable re-
armature assembly of the regulator
sistor (fig. 56) by turning the volt-
(cc, fig. 59).
a g e adjustment (fig. 57) (from the
( f ) Check the range of the adjustment
top or side of the regulator) clock-
o f the regulator by adjusting the
w i s e (full decrease).
(c) Turn the contact screw assembly
5-ohm adjustable resistor (fig. 56)
b y turning the voltage adjustment
s c r e w s first, (fig. 58), and tighten
s i d e of the regulator) from maxi-
t h e m after adjustments are made)
m u m clockwise (full decrease) to
c l o c k w i s e until a stable voltage is
m a x i m u m c o u n t e r c l o c k w i s e (full
reached as indicated in (d) b e l o w .
i n c r e a s e ) . The range should be at
(d) As the contact screw assembly ( c )
least 25.0 to 30.0 volts reading on
a b o v e , is turned in, voltage will
t h e dc voltmeter (4). If the volt-
r i s e , then drop, and then start to
age range reading is off center of
rise again. Proper point of adjust-
