Spring charge time measurementTwo binary inputs, SPRCHRGN and SPRCHRGD, indicate spring charging started andspring charged, respectively. The spring charging time is calculated from the difference ofthese two signal timings.The spring charging time SPRCHRT is available through the Monitored data view .Alarm limit checkIf the time taken by the spring to charge is more than the value set with the tSprngChrgAlmsetting, the subfunction generates the SPRCHRAL alarm.It is possible to block the SPRCHRAL alarm signal by activating the BLOCK binary input.12.18.7.8 Gas pressure supervisionThe gas pressure supervision subfunction monitors the gas pressure inside the arcchamber.The operation of the subfunction can be described by using a module diagram. All themodules in the diagram are explained in the next sections.ALMPRESLOPRESPRESLOPRESALMBLOCKBLK_ALM00-tPressAlm00-TPressLOANSI11000293-1-en.vsdANSI11000293 V1 ENFigure 240: Functional module diagram for circuit breaker gas pressure alarmThe gas pressure is monitored through the binary input signals LOPRES and ALMPRES.Pressure alarm time delayWhen the ALMPRES binary input is activated, the PRESALM alarm is activated after atime delay set with the tPressAlm setting. The PRESALM alarm can be blocked byactivating the BLOCK input.If the pressure drops further to a very low level, the LOPRES binary input becomes high,activating the lockout alarm PRESLO after a time delay set with the TPressLO setting. ThePRESLO alarm can be blocked by activating the BLOCK input.1MRK 511 287-UUS A Section 12Monitoring537Technical manual
