Schweitzer Engineering Laboratories SEL-351 - Set Reclose Supervision Logic (Bottom of Figure 6.2); Unlatch Reclose Supervision Logic (Bottom of Figure 6.2)

Date Code 20001006 Close and Reclose Logic 6-9
SEL-351 Instruction Manual
If 79CLS remains deasserted to logical 0 during this entire 79CLSD time window, when the time
window times out, the following occurs:
• No automatic reclosing takes place.
• Relay Word bit RCSF (Reclose Supervision Failure indication) asserts to logical 1 for
one processing interval.
• The reclosing relay is driven to the Lockout State.
The logic in the bottom of Figure 6.2 is explained in more detail in the following text.
Set Reclose Supervision Logic (Bottom of Figure 6.2)
Refer to the bottom of Figure 6.2. If all the following are true:
• The close logic output CLOSE (also see Figure 6.1) is not asserted (Relay Word bit
CLOSE = logical 0).
• The reclosing relay is not in the Lockout State (Relay Word bit 79LO = logical 0).
• The circuit breaker is open (52A = logical 0).
• The reclose initiation condition (79RI) is not making a rising edge (logical 0 to logical 1)
transition.
• The Reclose Supervision Limit Timer is not timed out (Relay Word bit RCSF =
logical 0).
then a reclosing relay open interval time-out seals in Figure 6.2. Then, when 79CLS asserts to
logical 1, the sealed-in reclosing relay open interval time-out condition will propagate through
Figure 6.2 and on to the close logic in Figure 6.1.
Unlatch Reclose Supervision Logic (Bottom of Figure 6.2)
Refer to the bottom of Figure 6.2. If the reclosing relay open interval time-out condition is sealed-
in, it stays sealed-in until one of the following occurs:
• The close logic output CLOSE (also see Figure 6.1) asserts (Relay Word bit CLOSE =
logical 1).
• The reclosing relay goes to the Lockout State (Relay Word bit 79LO = logical 1).
• The circuit breaker closes (52A = logical 1).
• The reclose initiation condition (79RI) makes a rising edge (logical 0 to logical 1)
transition.
• SELOGIC Control Equation setting 79CLS asserts (79CLS = logical 1).
• Or the Reclose Supervision Limit Timer times out (Relay Word bit RCSF = logical 1 for
one processing interval).
The Reclose Supervision Limit Timer is inoperative if setting 79CLSD = OFF. With
79CLSD = OFF, reclose supervision condition 79CLS is not time limited. When an open interval
times out, reclose supervision condition 79CLS is checked indefinitely until one of the other above
unlatch conditions comes true.
Courtesy of NationalSwitchgear.com