Co-generation mode
The Co-generation setting is intended for applications where
distributed generation is present on the load bushing side
of the voltage regulator, and where reverse power as a
result of feeder switching is not possible. When the control
is set for co-generation, a measured voltage from the load
bushing is required, but a source voltage is not required.
Figure 29 . Co-generation regulation points
METERING: See
. Always operates in the forward
direction except that load center voltage is calculated based
upon the reverse line-drop compensation settings (FC 54
and FC 55) when the fixed 1% reverse metering threshold
is exceeded. The Reverse Power indicator turns on when
this reverse threshold is crossed. The forward line-drop
compensation settings (FC 4 and FC 5) are used when the
current exceeds the fixed 1% forward metering threshold.
The demand values acquired during reverse power flow
are stored as reverse metered data, but the values are not
scaled (to reflect the other side of the regulator) since the
operating direction of the regulator never truly reverses.
Figure 30 . Co-generation metering
OPERATION: See
. The control always regulates
voltage in the forward direction. The control will regulate in
the forward direction, but will use the reverse settings for
set voltage (FC 51), bandwidth (FC 52), time delay (FC 53),
and line-drop compensation (FC 54 and FC 55) when the
real component of the current is above the fixed 1% reverse
metering threshold. The control will continue to use the
reverse settings until the real component of the current is
above the fixed 1% forward metering threshold.
Figure 31 . Co-generation mode operation
Reactive bi-directional mode
When FC 56 is set for Reactive Bi-directional, source
voltage is required, either measured or calculated.
This mode is recommended for installations where
reverse power flow may occur and the real component
of the current is below the operator-defined threshold
(FC 57), except where the source of reverse power is a
co-generation facility or independent power producer.
METERING: See
. A threshold level of 1% (.002
A) of the full load CT secondary current of .200 A is used
in setting the power direction. The metering will be forward
until the current exceeds the 1% threshold in the reverse
direction. At this time, the various parameters use the
reverse settings and the Reverse Power indicator turns on.
The control continues metering in reverse until the current
exceeds the 1% threshold in the forward direction, then the
parameter scaling reverts back to the normal and Reverse
Power indicator turns off.
OPERATION: See
. The control determines
which settings (forward/reverse) to use by sensing the
real and reactive components of the current. The control
operates in the forward direction whenever the magnitude
of the reactive component of the current exceeds the
operator-defined threshold (FC 57) in the negative direction.
The control also operates in the forward direction if the
magnitude of the real component of the current exceeds
the operator-defined threshold (FC 57) in the positive
direction while the magnitude of the reactive component
of the current is between the operator-defined thresholds
(FC 57). The control operates in the reverse direction using
the reverse settings at FC 51, FC 52, FC 53, FC 54, and FC
55 whenever the magnitude of the reactive component of
the current exceeds the operator-defined threshold (FC 57)
in the positive direction. The control also operates in the
reverse direction if the magnitude of the real component of
the current exceeds the operator-defined threshold (FC 57)
in the negative direction while the magnitude of the reactive
component of the current is between the operator-defined
thresholds (FC 57).
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INSTALLATION, OPERATION, AND MAINTENANCE INSTRUCTIONS
MN225003EN April 2018
CL-7 Voltage Regulator Control