Lock-Out Initiation - ABB REL650 Applications Manual

1MRK 506 334-UUS A
11.2.2.12
Application manual
through the input 52a is missing. Thus, the reclosing function is not ready for a new
reclosing cycle.
Normally, the signal UNSUCCL appears when a new trip and start is received after the last
reclosing shot has been made and the auto-reclosing function is blocked. The signal resets
after reset time. The "unsuccessful" signal can also be made to depend on CB position
input. The parameter UnsucClByCBChk should then be set to CBCheck, and a timer
tUnsucCl should be set too. If the CB does not respond to the closing command and does
not close, but remains open, the output UNSUCCL is set high after time tUnsucCl. The
Unsuccessful output can for example, be used in Multi-Breaker arrangement to cancel the
auto-reclosing function for the second breaker, if the first breaker closed onto a persistent
fault. It can also be used to generate a Lock-out of manual closing until the operator has
reset the Lock-out, see separate section.

Lock-out initiation

In many cases there is a requirement that a Lock-out is generated when the auto-reclosing
attempt fails. This is done with logic connected to the in- and outputs of the Autoreclose
function and connected to Binary IO as required. Many alternative ways of performing the
logic exist depending on whether manual closing is interlocked in the IED, whether an
external physical Lock-out relay exists and whether the reset is hardwired, or carried out
by means of communication. There are also different alternatives regarding what shall
generate Lock-out. Examples of questions are:
• Shall back-up time delayed trip give Lock-out (normally yes)
• Shall Lock-out be generated when closing onto a fault (mostly)
• Shall Lock-out be generated when the Auto-Recloser was OFF at the fault
• Shall Lock-out be generated if the Breaker did not have sufficient operating power for
an auto-reclosing sequence (normally not as no closing attempt has been given)
In figures 137 and 138 the logic shows how a closing Lock-out logic can be designed with
the Lock-out relay as an external relay alternatively with the Lock-out created internally
with the manual closing going through the Synchro-check function. An example of Lock-
out logic.
Section 11
Control
309