Superior Electric STABILINE WHR22 Series, Instructions Manual

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6.2.8. Soft Start
The soft start option controls the WHR Series Voltage
Regulator so that when power is applied the regulator’s
output voltage starts out approximately 10% low and
after a preset time delay, the output voltage ramps up
to the selected regulated output voltage.
When input power is lost, the soft start controls
automatically
drives the POWERSTAT power
module(s) to the minimum output voltage position using
the output power from a small uninterruptible power
supply (UPS). The UPS then turns off automatically.
For UPS care and maintenance see the UPS manual.
When regulator power is restored, the load voltage will
be approximately 7% less than the input voltage on
narrow range WHR Regulators and 13% less than the
input voltage on wide range models. After a short time
delay, the regulator output voltage ramps up to the
selected, regulated output voltage.
6.3. ALL-BUCK AND ALL-BOOST OPERATION
All WHR Series regulators can be connected to provide
all-buck (unit will only lower the input voltage) or
all-boost (unit will only increase the input voltage)
operation. This feature can be used to shift the nominal
voltage or to correct input voltages that are always
extremely high or extremely low.
6.3.1. 4.4.1 All-Boost Operation
When connected for all-boost, the units will bring extra
low voltages up to nominal, but will not correct high
input voltages. Since operation in the all-boost mode
will increase the voltage and heating in the WHR
regulator, the rated load current, and in some cases the
maximum rated nominal input voltage, must be
reduced. Refer to the “All Buck and All Boost Rating
Chart” for the all-boost ratings. For all-boost operation
the input line to each POWERSTAT variable
transformer must be moved from terminal 2 to terminal
5.
6.3.2. 4.4.2 All-Buck Operation
When connected for all-buck operation, the units will
bring extra high input voltages down to nominal, but will
not correct low input voltages. Since all-buck operation
reduces the voltage in the regulator, the nominal input
voltage can be increased. The current ratings remain
the same. Refer to the “All Buck and All Boost Rating
Chart” for all-buck ratings. All-buck operation requires
moving the input line to each POWERSTAT Variable
Transformer from terminal 2 to terminal 4.
All Buck and All Boost Rating Chart
Standard Rating
All Buck Operation All Boost Operation
(max output voltage = input voltage) (min output voltage = input voltage)
Maximum
Nominal
Input Voltage
§
Minimum
Output
Voltage
(% of
Input)
† High
Input
Voltage
Range
(% of
Output)
Maximum
Nominal
Input Voltage
§
Maximu
m Output
Voltage
(% of
Input)
‡ Low
Input
Voltage
Range
(% of
Output)
Current
De-rating
(% of
rated)
Voltage Range 50 Hz 60 Hz 50 Hz 60 Hz
240 X 208
Narrow 277 277 80% 125% 208 240 125% 75% 77%
Wide 300 300 67% 150% 208 240 150% 65% 72%
§ Selectable output voltage is a function of the control module and must remain within the limits specified in the unit rating charts.
† In all buck operation the input voltage range is from the selected output voltage to the 'high input voltage range'.
‡ In all boost operation the input voltage range is from the 'low input voltage range' to the selected output voltage.