12.2.2.17 Transient fault M12391-208 v3After the Reclosing command the reclaim timer keeps running for the set time. If no trippingoccurs within this time,tReclaim, the Auto-Reclosing will reset. The CB remains closed and theoperating gear recharges. The input signals CBPOS and CBREADY will be set12.2.2.18 Permanent fault and reclosing unsuccessful signal M12391-211 v4If a new trip occurs, and number of reclosing shots is set to 1, a new input signal START orTRSOTF appears, after the CB closing command, the output UNSUCCL (unsuccessful closing)is set high. The timer for the first shot can no longer be started. Depending on the set numberof Reclosing shots further shots may be made or the Reclosing sequence is ended. Afterreclaim timer time-out the Auto-Reclosing function resets, but the CB remains open. The “CBclosed” information through the input CBPOS is missing. Thus, the reclosing function is notready for a new reclosing cycle.Normally, the signal UNSUCCL appears when a new trip and start is received after the lastreclosing shot has been made and the auto-reclosing function is blocked. The signal resetsafter reclaim time. The “unsuccessful” signal can also be made to depend on CB position input.The parameterUnsucClByCBChk should then be set toCBCheck, and a timertUnsucCl shouldbe set too. If the CB does not respond to the closing command and does not close, butremains open, the output UNSUCCL is set high after timetUnsucCl. The Unsuccessful outputcan for example, be used in Multi-Breaker arrangement to cancel the auto-reclosing functionfor the second breaker, if the first breaker closed onto a persistent fault. It can also be used togenerate a Lock-out of manual closing until the operator has reset the Lock-out, see separatesection.12.2.2.19 Lock-out initiation M12391-214 v7In many cases there is a requirement that a Lock-out is generated when the auto-reclosingattempt fails. This is done with logic connected to the in- and outputs of the Autoreclosefunction and connected to Binary IO as required. Many alternative ways of performing the logicexist depending on whether manual closing is interlocked in the IED, whether an externalphysical Lock-out relay exists and whether the reset is hardwired, or carried out by means ofcommunication. 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 Autorecloser was OFF at the fault or for example, inSingle phase AR mode and the fault was multi-phase (normally not as no closing attempthas been given)• Shall Lock-out be generated if the Breaker did not have sufficient operating power for anauto-reclosing sequence (normally not as no closing attempt has been given)In figures 113 and 114 the logic shows how a closing Lock-out logic can be designed with theLock-out relay as an external relay alternatively with the Lock-out created internally with themanual closing going through the Synchro-check function. An example of Lock-out logic.Section 12 1MRK 505 363-UEN AControl224Application manual
