Schweitzer Engineering Laboratories SEL-311C - Section 6: Close and Reclose Logic; Overview; Close Logic; Reclose Supervision Logic

Date Code 20060320 Instruction Manual SEL-311C Relay
Section 6
Close and Reclose Logic
Overview
This section is made up of three subsections:
➤ Close Logic
➤ Reclose Supervision Logic
➤ Reclose Logic
Close Logic
This subsection describes the final logic that controls the close output contact
(e.g., OUT103 = CLOSE). This output contact closes the circuit breaker for
automatic reclosures and other close conditions (e.g., manual close initiation
via serial port or optoisolated inputs).
If automatic reclosing is not needed, but the SEL-311C Relay is to close the
circuit breaker for other close conditions (e.g., manual close initiation via
serial port or optoisolated inputs), then this subsection is the only subsection
that needs to be read in this section (particularly the description of SEL
OGIC
®
control equation setting CL).
Reclose
Supervision Logic
This subsection describes the logic that supervises automatic reclosing when
an open interval time times out—a final condition check right before the close
logic asserts the close output contact.
Reclose Logic
This subsection describes all the reclosing relay settings and logic needed for
automatic reclosing (besides the final close logic and reclose supervision logic
described in the previous subsections).
The reclose enable setting, E79, has setting choices N, 1, 2, 3, and 4. The
default setting E79 = N defeats the reclosing relay. Setting choices 1–4 are the
number of desired automatic reclosures.
NOTE: Setting E79 = N defeats the
reclosing relay, but does not defeat
the ability of the close logic described
in the first subsection (Figure 6.1) to
close the circuit breaker for other
close conditions via
SELOGIC control
equation setting CL (e.g., manual close
initiation via serial port or
optoisolated inputs).