6.19
Date Code 20060320 Instruction Manual SEL-311C Relay
Close and Reclose Logic
Reclosing Relay
CLOSE off until the circuit breaker status indication tells the relay that the
breaker is closed. The circuit breaker anti-pump circuitry should take care of
the TRIP and CLOSE being on together for a short period of time.
Other Settings Considerations
1. In the preceding additional setting example, the reclose initiate
setting (79RI) includes input IN101, that is connected to a 52a
breaker auxiliary contact (52A = IN101).
If a 52b breaker auxiliary contact is connected to input IN101
(52A = !IN101), the reclose initiate setting (79RI) remains the
same.
2. If no reclose initiate supervision is desired, make the following
setting:
Setting 79RIS = logical 1 at all times. Any time a logical 0 to
logical 1 transition is detected by setting 79RI, open interval
timing will be initiated (unless prevented by other means).
3. If the following setting is made:
reclosing will never take place (reclosing is never initiated).
The reclosing relay is effectively inoperative.
4. If the following setting is made:
reclosing will never take place (the reclosing relay goes directly
to the lockout state any time reclosing is initiated). The
reclosing relay is effectively inoperative.
Drive-to-Lockout and
Drive-to-Last Shot
Settings (79DTL and
79DLS, Respectively)
When 79DTL = logical 1, the reclosing relay goes to the Lockout State (Relay
Word bit 79LO = logical 1), and the front-panel LO (Lockout) LED
illuminates.
79DTL has a 60-cycle dropout time. This keeps the drive-to-lockout condition
up 60 more cycles after 79DTL has reverted back to 79DTL = logical 0. This
is useful for situations where both of the following are true:
➤ Any of the trip and drive-to-lockout conditions are “pulsed”
conditions (e.g., the OPE command Relay Word bit, OC,
asserts for only 1/4 cycle—refer to the Settings Example on
page 6.20).
➤ Reclose initiation is by the breaker contact opening (e.g.,
79RI = !52A—refer to Additional Settings Example on
page 6.18).
Then the drive-to-lockout condition overlaps reclose initiation and the
SEL-311C stays in lockout after the breaker trips open.
When 79DLS = logical 1, the reclosing relay goes to the last shot, if the shot
counter is not at a shot value greater than or equal to the calculated last shot
(see Reclosing Relay Shot Counter on page 6.16).
79RI = !52A
79RIS = 1 (numeral 1)
79RI = 0 (numeral 0)
79RIS = 0 (numeral 0)
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