SR 4 GENERATOR
SYSTEMS OPERATION
MANUAL VOLTAGE CONTROL ATTACHMENT
The location of the manual voltage control panel can
be up to 76 ft. (23.2 meters) from the generator. Make
reference to the chart.
CONTROL PANEL LOCATION
WIRE SIZE (AWG)
MAXIMUM CABLE LENGTH
No. 18
30 ft. (9.1 meters)
No. 16
48 ft. (14.6 meters)
No. 14
76 ft. (23.2 meters)
The manual voltage control can be used to control
generator voltage when there is a failure in the generator
regulator assembly. It will manually control the rate at
which control rectifier CR9 is turned on. For information
on CR9 operation make reference to OPERATION OF
GENERATOR.
NOTE: CR9 and CR10 must be able to
operate correctly for the manual voltage
control to work.
The manual voltage control has a switch (1), voltage
control rheostat (2), flash button (3) and a control
assembly.
VOLTAGE CONTROL PANEL
1. Switch (OFF, AUTO and MAN positions). 2. Voltage
control rheostat. 3. Flash button.
Switch (1) is used to make the' selection between
AUTO, MAN and OFF. In the "AUTO" position the
generator regulator assembly controls the generator
voltage. In the “OFF" position the generator voltage will
go to zero. In the "MAN" position generator voltage is
controlled by voltage control rheostat (2).
Flash button (3) is used when the generator voltage
does not build up. With switch (1) in the "MAN" position
push flash button (3) until the generator voltage starts to
build up.
NOTICE
Press the flash button only until the
generator voltage starts to build up.
If the button is held too long the
voltage will increase to above the
capacity of the generator. This can
cause the line circuit breaker to trip
or the regulator fuse to open.
When flash button (3) is pushed AC current from the
generator is rectified by a diode on the manual voltage
control panel. This rectified (DC) current goes directly to
the generator exciter field. It does not go through control
rectifier CR9.
CONTROL ASSEMBLY
4. Trigger module. 5. Terminal strip. (4 and
5 are not serviced separately - lowest
serviceable level is Manual Voltage Control
Assembly)
The control assembly is on the back side of the
mounting bracket for regulator module A1. The control
assembly has terminal strip (5) and trigger module (4).
When switch (1) is in the "MAN" position, the action of
electrical circuits in trigger module (4) control the amount
of "on" time for control rectifier CR9.
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