Crankcase Breather; S S E E C C T T I I O O N N 2 2 - Guardian Quietpact 55 Repair Manual

S S e e c c t t i i o o n n 2 2

M M A A J J O O R R G G E E N N E E R R A A T T O O R R C C O O M M P P O O N N E E N N T T S S
Rotor will be lost. The unit's AC output voltage will
then drop to a value commensurate with the Rotor's
residual magnetism (about 7-12 VAC).
Figure 2-6. – Excitation Circuit Breaker
VOLTAGE REGULATOR:
Six (6) leads are connected to the voltage regulator
as follows:
• Two (2) SENSING leads deliver ACTUAL AC out-
put voltage signals to the regulator. These are
Wires No. 11S and 22S.
• Two (2) leads (4 and 0K) deliver the regulated
direct current to the Rotor, via brushes and slip
rings.
• Two (2) leads (No. 6 and 2A) deliver Stator excita-
tion winding AC output to the regulator.
Figure 2-7. – Voltage Regulator
The regulator mounts a "VOLTAGE ADJUST" poten-
tiometer, used for adjustment of the pre-set REFER-
ENCE voltage. A lamp (LED) will turn on to indicate
that SENSING voltage is available to the regulator
and the regulator is turned on.
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ADJUSTMENT PROCEDURE:
With the frequency set at 62.5 Hertz and no load on
the generator, slowly turn the voltage adjust pot on
the voltage regulator until 124 VAC is measured. If
voltage is not adjustable, proceed to Section 6 -
Troubleshooting; Problem 2.
NOTE: If, for any reason, sensing voltage to the
regulator is lost, the regulator will shut down and
excitation output to the Rotor will be lost. The AC
output voltage will then drop to a value that is
commensurate with Rotor residual magnetism
(about 7-12 VAC). Without this automatic shut-
down feature, loss of sensing (actual) voltage to
the regulator would result in a "full field" or "full
excitation" condition and an extremely high AC
output voltage.
NOTE: Adjustment of the regulator's "VOLTAGE
ADJUST" potentiometer must be done only when
the unit is running at its correct governed no-load
speed. Speed is correct when the unit's no-load
AC output frequency is about 62.5 Hertz. At the
stated frequency, AC output voltage should be
about 124 volts.

CRANKCASE BREATHER

Figure 2-8. – Crankcase Breather
DESCRIPTION:
The crankcase breather is equipped with a reed valve
to control and maintain a partial vacuum in the
crankcase. The breather is vented to the intake