6-20 Close and Reclose Logic Date Code 20001006
SEL-351 Instruction Manual
The shot counter also increments for sequence coordination operation. The shot counter can
increment beyond the last shot for sequence coordination [see Sequence Coordination Setting
(79SEQ) later in this subsection].
Reclosing Relay SELOGIC Control Equation Settings Overview
Table 6.4: Reclosing Relay SELOGIC Control Equation Settings
SELOGIC Control
Equation Setting Factory Setting Definition
79RI TRIP Reclose Initiate
79RIS 52A + 79CY Reclose Initiate Supervision
79DTL OC + !IN2 + LB3 Drive-to-Lockout
79DLS 79LO Drive-to-Last Shot
79SKP 0 Skip Shot
79STL TRIP Stall Open Interval Timing
79BRS 0 Block Reset Timing
79SEQ 0 Sequence Coordination
79CLS 1 Reclose Supervision
These settings are discussed in detail in the remainder of this subsection.
Reclose Initiate and Reclose Initiate Supervision Settings (79RI and 79RIS, Respectively)
The reclose initiate setting 79RI is a rising-edge detect setting. The reclose initiate supervision
setting 79RIS supervises setting 79RI. When setting 79RI senses a rising edge (logical 0 to
logical 1 transition), setting 79RIS has to be at logical 1 (79RIS = logical 1) in order for open
interval timing to be initiated.
If 79RIS = logical 0 when setting 79RI senses a rising edge (logical 0 to logical 1 transition), the
relay goes to the Lockout State.
Factory Settings Example
With factory settings:
79RI = TRIP
79RIS = 52A + 79CY
the transition of the TRIP Relay Word bit from logical 0 to logical 1 initiates open interval timing
only if the 52A + 79CY Relay Word bit is at logical 1 (52A = logical 1, or 79CY = logical 1).
Input IN1 is assigned as the breaker status input in the factory settings (52A = IN1).
The circuit breaker has to be closed (circuit breaker status 52A = logical 1) at the instant of the
first trip of the auto-reclose cycle in order for the SEL-351 to successfully initiate reclosing and
Courtesy of NationalSwitchgear.com
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