BE1-951
Application
8-9
and timing. This prevents the reset timer from resetting the reclose function for a situation where a 51
element is just above pickup and the time to trip is longer than the reset time.
Operation - Setting Group Selection
A setting group can be selected automatically or by using the communication ports or the front panel HMI.
Automatic setting group changes are based on current level and duration. Automatic setting group changes
for cold load pickup and/or dynamic setting adjustments are enabled by the SP-GROUP# command. Setting
group changes initiated by contact sensing inputs are not accommodated in this scheme, but IN2, IN3, or
IN4 can be programmed to provide this function.
Operation - Alarms
If the continuous self-test diagnostics of the relay detect an error, failsafe output contact OUTA will close and
the Relay Trouble LED of the HMI will light. OUTA will also close if relay operating power is lost. More
information about alarms is provided in Section 6,
Reporting and Alarm Functions.
Outputs OUT4 and OUT5 are assigned to indicate user specified Major or Minor alarms. OUT4 indicates
Minor alarms and OUT5 indicates Major alarms. The user has the ability to specify which alarms are
announced as Major or Minor alarms. When an alarm is detected, the appropriate front panel LED will light
to indicate the alarm. Note that some alarms are non-latching and will clear when the alarm condition goes
away. Other alarms require a reset either by operating the front panel Reset pushbutton or by issuing ASCII
commands through a communication port. More information about alarms is provided in Section 6,
Reporting
and Alarm Functions.
Table 8-5. OC-W-79 Contact Sensing Input Logic
Input
Purpose
Variable Label
State Labels
Closed (1)
Open (0)
IN1
51b breaker status (TRUE when breaker is open).
Used for breaker status indication in Sequence of
Events Reports, recloser control, and breaker
monitoring
BREAKER
OPEN
CLOSED
IN2
Reclosing Drive to Lockout. Drives recloser to lockout
when de-energized. Can be used with an external
switch to disable the recloser. If IN2 is not used, it
must be strapped high to enable the recloser.
RCL_DTL
NORMAL
DTL
IN3
Reclosing initiate used to initiate reclosing by external
protective relays.
RCL_INI
INI
NORMAL
IN4
When IN4 is energized, Neutral, Negative Sequence,
50 and 51 protection is enabled. IN4 must be tied
HIGH if this feature is not used.
N&Q_ENABLE
ENABLED
DISABLED
Table 8-6. OC-W-79 Function Block Logic
Function
Purpose
BESTlogic
Expression
Mode Setting
50TP
Block when recloser sequence controlled blocking
output is TRUE.
79SCB
1
(enabled)
NOTE
When using OUT1 through OUT5 as alarm outputs, remember that
these outputs do not have normally closed, failsafe output contacts.
