Switch Control Setup
the control resets the sectionalizing timers and counters to zero. Configure this
setpoint if the Successful Reclose Reset Time setting has been implemented in
the source-side protective device. Set the value to the same value as the source-side
protective device. When the source-side protective device does not use this reset
scheme, set the value to the N/A setting; the switch control will use the Sectionalizer
Reset and Extended Voltage Loss Time setting to reset the count. (Range: 1-255;
Step: 1; Default: N/A)
Overcurrent to Volt Loss Association Time (tenths)
This setpoint denes the time interval between the end of a detected overcurrent event
and the start of a detected three-phase voltage loss for the purpose of associating the
two events to count breaker operations. Under normal circuit conditions, leave this set to
the factory default of six-tenths. When the line voltage will be supported for an abnormal
period of time following the breaker operation, adjust this setpoint to account for it.
(Range: 6-60; Step: 1; Default: 6)
Fault Current Required before First/All Voltage Loss(es)
For the switch control to trip open the switch because of an overcurrent event, it must
detect and count fault-current and voltage-loss events. If this setpoint is set to the All
setting, the switch control only increments counts if it detects fault current before
every voltage loss. Any voltage loss without an associated fault current disarms the
sectionalizer. If set to the First setting, the switch control must detect fault current only
before the rst voltage loss. After that, the recloser operation count increments with
each voltage loss. When the count is reset, the next voltage loss must be preceded by
fault current for the switch control to start counting again. The current transformers are
load-metering CTs (not fault current CTs); and they may not register subsequent faults
correctly after the rst fault. (Default: First)
First-Reclose Qualification Time (seconds)
In some recloser congurations that implement an initial instantaneous reclose strategy,
the three-phase voltage loss cannot be reliably detected or is missed by the sectionalizing
logic that counts recloser operations. The First-Reclose Qualication Time feature
requires a detected three-phase loss of voltage to persist longer than the congured
time for it to register as the rst sectionalizing count. This allows controls to ignore an
initial instantaneous reclose should it be detected. After the rst qualied sectionalizing
count in a series has been recorded, subsequent voltage losses are not qualied by this
time before being counted for purposes of sectionalizer operation. All detected voltage
losses are entered in the events log, whether qualied for sectionalizing count or not, and
a voltage loss disqualied by this criterion is logged as an instantaneous reclose and is
not counted for purposes of sectionalization. (Range: 0.1-6.0 seconds; Step: 0.1; Default:
Disabled) See the “(Enhanced) First-Reclose Qualication Time” section on page 40.
Note: This time represents an additional qualification period after the detection of the
voltage loss during which the control determines whether to count it for sectionalizing
purposes. It is distinct from the Loss of Voltage Threshold Maximum Response Time
function, which varies based on the Loss of Voltage Threshold setting configured on
the Setup>General>Site Related screen. The detection threshold applies to all voltage
losses. The First-Reclose Qualification Time feature allows the control to disqualify
any potentially detected voltage loss, such as those caused by initial instantaneous
reclose operations, and disregard them only for purposes of sectionalizing. It is applied
to detected voltage losses only until the first qualified recloser operation in a series has
been recorded.
When this feature is used, the memory time from the first recloser operation to reset
will be counted from the first qualified breaker operation count in the series recorded
by the control, and not from the disqualified instantaneous first-reclose operation, if it
is detected.
Note: When the First-Reclose Qualification Time setting is enabled and the breaker
uses an instantaneous first reclose, the configured number of breaker shots-to-lockout
events must be increased by one because the switch control will ignore the first instan-
taneous breaker operation should it be detected and disqualified.
S&C Instruction Sheet 1045-530 39
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