Superior Electric STABILINE WHR34 T Series, Инструкция по эксплуатации

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6
5.0.
OPERATION
5.1. CONTROL MODULE ASSEMBLY
5.1.1.
General
The control modules contain the circuitry that senses
the output voltage and determine if correction is
needed. When correction is required this circuit sends a
raise or lower signal to the motor driven variable
transformers. To eliminate unauthorized tampering of
the control module the items marked (
♦
) below are
located behind the front panel.
5.1.2. Power Pilot Lamps (A1-LP1)
The POWER lamp on each control assembly lights
when power is present for the motor on that phase. This
indicates the voltage regulator is energized.
5.1.3. Control Pilot Lamps ( A1-LP2)
The CONTROL lamp lights when the control assembly
sense voltage for that phase is energized. The control
sense voltage must be energized for automatic
correction of voltage changes to occur.
5.1.4. Analog Voltmeters (A1-M1)
These meters show the output voltages. There is one
meter for each phase. They sense line-to-neutral
voltage, and display line-to-neutral voltage and the
equivalent line to line voltage.
5.1.5. Output Voltage Range Toggle Switches
(A1-S1)
♦
With these switches in the OFF position, the control
sense voltage for that phase is disconnected and the
control pilot lamp is not illuminated. In this position
automatic correction for voltage changes on that phase
will not take place and any change in input voltage will
be reflected in output voltage. The switches (one for
each phase) should be placed in either the “380Y/220”
or “480Y/277” position to energize the control assembly
sense voltage and allow automatic correction of voltage
changes.
5.1.6. Output Voltage Potentiometers
♦
These potentiometers set the line to neutral output
voltages, one for each phase. The adjustment range is
approximately ± 10% of selected nominal output
voltage.
5.1.7. Sensitivity Potentiometers
♦
These potentiometers adjust the voltage regulator’s
output accuracy and therefore set how much the output
voltage will change before the unit will correct. There is
a SENSITIVITY potentiometer for each sensed phase.
5.1.8. Fuses (A1-F1 to A1-F4)
♦
The four fuses located on the control module protect
the motor and sense power lines. If the POWER or
CONTROL lights are not lit, and all control settings are
proper, check for a blown fuse.
5.2. SETTING OUTPUT VOLTAGE AND
SENSITIVITY POTENTIOMETERS
Normally, the WHR Series voltage regulator should not
be operated without the front panel(s) of the cabinet in
place. However, during the initial operation of the
regulator, the front panels can be removed to allow
setting the OUTPUT VOLTAGE and SENSITIVITY
potentiometers.
5.2.1. Energize Regulator
On units equipped with a manual bypass switch ensure
it is in the REGULATOR position. Energize the
regulator power source and place the input circuit
breaker, if so equipped, in the "ON" position. The pilot
lamps should light, indicating that the voltage regulator
is energized and that the control unit is on. If
necessary, move the OUTPUT VOLTAGE RANGE
switch on each phase to the desired nominal output
voltage position. The voltmeters will indicate the output
voltages.
5.2.2. Set Output
To adjust the output voltage on any phase, turn the
OUTPUT VOLTAGE potentiometer clockwise to
increase or counterclockwise to decrease the output
voltage, as indicated on the voltmeter for that phase.
5.2.3. Set Sensitivity
The sensitivity must be adjusted if the voltage regulator
hunts (any of the motor driven variable transformer
sections of the regulator continually cycles back and
forth) or if the regulator allows too great a change from
the set voltage before correction occurs.
Turning the SENSITIVITY control clockwise increases
the sensitivity to maximum (±0.75% to ±1% output
voltage accuracy). For maximum sensitivity, turn the
SENSITIVITY control on one phase clockwise to the
point where the POWERSTAT on that phase begins to
hunt. Turn the control counterclockwise (CCW) until the
hunting stops. Turn the control an additional 1/4 turn
CCW. Repeat for the other two phases.
5.2.4. Close
Replace the front cover(s).
5.3. REMOTE SENSING
Normally, these voltage regulators sense and regulate
each line to neutral voltage at the regulator's output
terminals, In some cases better control can be obtained
by regulating the voltage at another point, such as at
the end of long lines between the regulator and the
load. This is known as remote sensing.
If remote sensing is desired, move the wire connected
to terminal 6 to terminal 7 and the wire connected to
terminal 8 to terminal 9 on each control module
terminal panel. This will disconnect the control module
sense terminals from the output terminals of the
regulator. Connect remote sensing wires for each