Single Alarm Memory (BD49)
BOOL1, BOOL2, BOOL3:BOOL;
FB : LIB.CORE.V1_0.BD49_SINGLEALARMMEMORY;
BOOL3 := FB.MEMORY;
This block is dedicated to deal with alarm states. The alarm signal is at the IN input. A rising edge on the IN input sets MEMORY to TRUE (alarm memory). The alarm can be reset by a rising edge at the RESET input. If IN=FALSE at the reset time, then MEMORY goes to FALSE. If the alarm is active (IN=TRUE), it can not be reset by the RESETinput, but may be acknowledged by a rising edge brought to the ACK input.
||Input of the alarm signal
||Acknowledge. If IN=TRUE and rising edge comes to ACK then ACKNOWLEDGED=TRUE (while keeping MEMORY=TRUE)
||Reset of the alarm memory and ACKNOWLEDGED output
||Indication that an alarm has been acked
||Status of the alarm block (bit 8 indicates IN=TRUE, bit 9 indicates ACKNOWLEDGED=TRUE, bit 10 indicates MEMORY=TRUE)
This alarm is activated by the b1 input. It is not acknowledged (input ACK is not connected), so it can only be reset after b1 is FALSE again.