• CBREADY, CB ready for a reclosing cycle, for example, charged operating gear.• 52a to ensure that the CB was closed when the line fault occurred and start wasapplied.• No signal at input INHIBIT that is, no blocking or inhibit signal present. After thestart has been accepted, it is latched in and an internal signal “Started” is set. It can beinterrupted by certain events, like an “Inhibit” signal.12.2.2.3 Initiate auto-reclosing from CB open informationIf a user wants to initiate auto-reclosing from the "CB open" position instead of fromprotection trip signals, the function offers such a possibility. This starting mode is selectedwith the setting parameter StartByCBOpen=Enabled. It is then necessary to blockreclosing for all manual trip operations. Typically CBAuxContType=NormClosed is alsoset and a CB auxiliary contact of type NC (normally closed, 52b) is connected to inputs52a and RI. When the signal changes from “CB closed” to “CB open” an auto-reclosingstart pulse is generated and latched in the function, subject to the usual checks. Then thereclosing sequence continues as usual. One needs to connect signals from manual trippingand other functions, which shall not be reclosed automatically to the input INHIBIT.12.2.2.4 Blocking of the autorecloserAuto-Reclose attempts are expected to take place only for faults on the own line. TheAuto-Recloser must be blocked by activating the INHIBIT input for the followingconditions:• Tripping from Delayed Distance protection zones• Tripping from Back-up protection functions• Tripping from Breaker failure function• Intertrip received from remote end Breaker failure function• Busbar protection trippingDepending of the starting principle (General Trip or only Instantaneous trip) adoptedabove the delayed and back-up zones might not be required. Breaker failure trip local andremote must however always be connected.12.2.2.5 Control of the auto-reclosing open time for shot 1Up to four different time settings can be used for the first shot, and one extension time.There are separate settings for single-, two- and three-phase auto-reclosing open time, t11Ph, t1 2Ph, t1 3Ph. If no particular input signal is applied, and an auto-reclosing programwith single-phase reclosing is selected, the auto-reclosing open time t1 1Ph will be used.If one of the inputs TR2P or TR3P is activated in connection with the start, the auto-reclosing open time for two-phase or three-phase reclosing is used. There is also a separateSection 12 1MRK 505 337-UUS -Control306Application manual
