Status Recognition And Monitoring Of The Circuit Breaker - Siemens SIPROTEC 7SJ62 Manual

Functions
2.14 Automatic Reclosing System 79
• The circuit breaker is not ready after the breaker monitoring time has elapsed, provided that the circuit
breaker check has been activated (address 7113 CHECK CB? = Chk each cycle, indicated by „79 T-
CBreadyExp").
• The circuit breaker is not ready after maximum extension of the dead time Max. DEAD EXT.. The monitor-
ing of the circuit breaker status and the synchrocheck may cause undesired extension of the dead time. To
prevent the automatic reclosure system from assuming an undefined state, the extension of the dead time
is monitored. The extension time is started when the regular dead time has elapsed. When it has elapsed,
the automatic reclosure function is blocked dynamically and the lock-out time launched. The automatic re-
closure system resumes normal state when the lock-out time has elapsed and new blocking conditions do
not apply (indicated by „79 TdeadMax Exp") .
• Manual closing has been detected (externally) and parameter BLOCK MC Dur. (T = 0) was set such that
the automatic reclosing system responds to manual closing,
• Via a correspondingly masked binary input (FNo. 2703 „>BLOCK 79"). If the blocking takes places while
the automatic recloser is in normal state, the latter will be blocked statically („79 is NOT ready"). The
blocking is terminated immediately when the binary input has been cleared and the automatic reclosure
function resumes normal state. If the automatic reclosure function is already running when the blocking ar-
rives, the dynamic blocking takes effect („79 DynBlock"). In this case the activation of the binary input
starts the dynamic blocking time SAFETY 79 ready. Upon its expiration the device checks if the binary
input is still activated. If this is the case, the automatic reclosure program changes from dynamic blocking to
static blocking. If the binary input is no longer active when the time has elapsed and if no new blocking con-
ditions apply, the automatic reclosure system resumes normal state.
2.14.3

Status Recognition and Monitoring of the Circuit Breaker

Circuit Breaker Status
The detection of the actual circuit breaker status is necessary for the correct functionality of the auto reclose
function. The breaker status is detected by the circuit breaker auxiliary contacts and is communicated to the
device via binary inputs 4602 „>52-b" and 4601 „>52-a" .
Here the following applies:
• If binary input 4601 „>52-a" and binary input 4602 „>52-b" are used, the automatic reclosure function
can detect whether the circuit breaker is open, closed or in intermediate position. If both auxiliary contacts
detect that the circuit breaker is open, the dead time is started. If the circuit breaker is open or in intermediate
position without a trip command being present, the automatic reclosure function is blocked dynamically if it
is already running. If the automatic reclosure system is in normal state, it will be blocked statically. When
checking whether a trip command applies, all trip commands of the device are taken into account irrespec-
tive of whether the function acts as starting or blocking element on behalf of the automatic reclosure pro-
gram.
• If binary input 4601 „>52-a" alone is allocated, the circuit breaker is considered open while the binary input
is not active. If the binary input becomes inactive while no trip command of (any) function applies, the auto-
matic reclosure system will be blocked. The blocking will be of static nature if the automatic reclosure system
is in normal state at this time. If the automatic reclosing system is already running, the blocking will be a
dynamic one. The dead time is started if the binary input becomes inactive following the trip command of a
starting element 4601 „>52-a" = inactive). An intermediate position of the circuit breaker cannot be detect-
ed for this type of allocation.
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SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008