P-9-TM-457-35
T.O. 35C2-3-442-2
TM 5-6115-457-34
TM-07464A-35
CT4, CT5, CT6, on the load lines of the
5. The generator output voltage is
generator (figures 1-4 and 1-5). The volt-
determined by the level of the reference
age at L-M of connector J13 is from phase
voltage and is controlled by the setting of
C (T9 - T12 on generator). The two inputs
R33 which adjusts the range voltage and
are combined by T1 (figures 1-24 and 1-26)
operators rheostat (R2, figures 1-4 and
1-5 ) which sets the actual output. During
under control of winding 5-7, then rectified
by bridge CR1 through CR4 and fed to the
parallel operation, the reference voltage is
dependent on the cross current compensa-
exciter field stator winding from S-R of
connector J13. In the event of a short cir-
tion network. For example, if one genera-
tor draws more current, the network will
cuit, the voltage at L-M can drop to zero
but there is a high voltage at J-K from the
increase the magnitude of the reference
current transformers so that the exciter
voltage causing the voltage regulator to
sense more voltage and thereby causing a
provides sufficient field for the generator
decrease in current to the exciter field
output to actuate the protective devices to
stator winding. This provided parallel
shut down the set.
operation with droop.
3. The voltage at S-R of connector
6. Power for the transistor ampli-
J13 is compared to the reference voltage at
Q1 (located in voltage regulator A10) and
fiers and the control winding (5-7 of Tl)
Zener diode VR1 of the differential ampli-
current is obtained from pins L-M of con-
fier Q1 - Q2. Any difference or error sig-
nector J13 thru stepdown transformer T4
nal at the collector of Q2 is amplified by
and bridge rectifier CR8 through CR11.
Q5 - Q6 and Q3 - Q4 and then fed to the
Diode CR17 and resistor R21 provide posi-
control winding 5-7 of the control trans -
tive feedback to the amplifiers to enhance
former T1 which increases or decreases
the gain.
the exciter field coil current to reduce the
7. When the start switch of the gen-
error signal to zero thereby maintaining
the output of the generator set within the
erator set is actuated, 24 volts D. C. is
applied to the exciter field stator windings
range as preset by R33. The networks
at pins S-R of connector J13 thru the limit-
R31-C1 and R32-C3 are utilized for phase
shift compensation. If hunting is present,
ing resistor R17A, R17B and isolation diode
CR16 from input pins C-D of connector J11
adjustment of R32 will provide the proper
(field flashing). The purpose is to quickly
amount of feedback to eliminate the hunting.
build up the magnetic field in the main
Adjustment of R31 will smooth and improve
rotor windings to produce an immediate
the transient response.
output from the generator. The flashing
voltage is then automatically removed.
4. The voltage at pins A-B of con-
nector J9 is derived from phase C (T9 -
6-75. TEST AND REMOVAL. .
T12 on generator) through the operators
-- ----
voltage adjust rheostat and from the cross
a. Symptom and Isolation of Malfunc-
current compensation network (figures 1-4
tion. A malfunction of the voltage regulator
and 1-5) when two or more generator sets
section (Al0) is usually indicated by a high
are connected in parallel. This voltage is
generator output voltage with no control.
stepped down in transformer T5, rectified
A malfunction of the exciter section (A11)
by bridge CR12 - 15, filtered by R16, R22,
is usually indicated by no generator output
C2, C5 and fed to the reference side of the
or by low output voltage when the load is
differential amplifier Q1- Q2.
6-40
