L DB12.DBB 7 <=== What line for DB ?

BTI

L 0

==I

FP "PULSO_RELATA_AMONIA"

= #pulso

the first variable of Relogio is HORA_ATUAL, this varible is DATE_AND_TIME class, and start in byte 4 in DB 12, son the byte 7 is the byte 3 of HORA_ATUAL this byte correspond to the hour of day. according to the struct of DATE_AND_TIME variables.

So your program sends pulses for one PLC cycle each time the hour change from 23 to 0, it means a change of day.

Best regards