Superior Electric STABILINE WHR32 Series, Instructions Manual

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5
2.3. THEORY OF OPERATION
These units regulate AC voltage by automatically
adjusting POWERSTAT
®
Variable Transformers to
maintain constant output voltage.
Each of the three solid-state control units detects one
line to neutral output voltages and continually compares
it with output and accuracy settings selected by the
user. If any line to neutral voltage is out of
specifications, the control unit on that phase drives the
POWERSTAT variable transformer on that phase, by
means of a synchronous motor, to the required new
position.
3.0.
INSTALLATION
3.1. TRANSPORTING THE REGULATOR
Due to its weight and size, proper lifting procedures
must be followed when transporting the unit and moving
it into the location where it is to be installed.
The proper method for moving these units is to place a
forklift under the base. A heavy frame is provided in this
area to allow lifting the unit in this manner without
damage. The 26 inch (559 mm) wide enclosures can
also be lifted by removing the top cover and using the
lifting eyes provided in the sides of the cabinet.
3.2. MECHANICAL INSTALLATION
The voltage regulator is designed for floor mounting.
When mounting the unit, allow a minimum clearance of
4 inches (100 mm) behind the unit for proper ventilation.
All internal components and wiring connections are
accessible through the front panels. A 3 foot (1000 mm)
area in front of the unit should be kept clear for
installation and service.
3.3. ELECTRICAL INSTALLATION
All WHR Series voltage regulators are designed to be
hard-wired to the input power and the load using copper
wire. When these units increase low input voltage to
give nominal output voltage, the input current is
substantially higher than the output current. Maximum
rated input and output currents for each unit are given
in the enclosed rating charts. Select a wire size that is
adequate to carry the maximum rated current as
specified by local and national code requirements.
The front panel(s) of the voltage regulator must be
removed to allow access to the input and load
terminals. To remove a panel, use a flat blade
screwdriver to release the ¼ turn fasteners, which hold
the front panel in place, and lift the panel off the base. A
full range of knockouts are provided in the base and the
rear panel of the unit for wire entry and exit.
The location of the power connections varies depending
on the options provided. On units with an input circuit
breaker, input connections are made directly to the
circuit breaker. On units without any options, the input
connections are located on the POWERSTAT variable
transformer. The input power connections are labeled
L1, L2, and L3 for the three hot lines. Load connections
are labeled T1, T2, and T3 for the hot lines and are
made to the POWERSTAT variable transformer on
units without any options.
In some cases the unit consists of more than one
enclosure. In these cases each enclosure will be
labeled “L” for input and “T” for output. In installing
multiple enclosure units refer to the second page of the
schematic supplied for point to point connections.
The input/output neutral is labeled NEUT. The input
neutral must be connected unless a zig-zag transformer
option is included.
WHR62 and WHR92 series have a zig-zag or neutral
generating transformer included.
The input neutral
MUST NOT be connected to either of these series
units.
The transformer in the WHR62 series is for
internal use only and no external neutral should be
connected. The zig-zag transformer in a WHR92 series
is designed to support the full rated output neutral of the
unit.
The ground terminals are a ground stud on the cabinet
wall, or a lug on the base, and must be connected to a
suitable earth ground to reduce the chance of electrical
shock.
4.0.
START UP
Set the Output Voltage Range toggle switch on each
control module to either the 280Y/120 or the 240Y/138
volt position to match your application. Use the
240Y/138 volt position for 220Y/127 and 230Y/132 volt
systems. The Output Voltage Adjustment and the
Sensitivity potentiometers are set at the factory for
nominal output voltage and approximately 2% accuracy,
and should not be readjusted until the voltage regulator
is initially energized.
After all input and output connections are completed
and checked, place the front panel(s) in position and
tighten the fasteners.
Energize the regulator power source and, if provided,
place the voltage regulator's circuit breaker in the "ON"
position. The voltmeter should indicate the output
voltage, and the POWER pilot lamps and the
CONTROL pilot lamps should be lit. This indicates the
voltage regulator is operating properly.