Hello guys, I need help. I'm trying to use the digital outputs on X121 (on Siemens 840D PL), to control a device. At the beginning of the program I insert the instruction A_OUT $ [1] = 1, the output goes to 1, but if I stop the program (with reset button ) BEFORE to execute the instruction $ A_OUT [1] = 0, the output remains to 1! I need that the output goes to 0 when I reset the program. Is possible to do It without changing the PLC? Is there a parameter to obtein it?

Thank you!!!

Can you give me an example?

Thank you for your help.

KiKi

what do you not understand?

there is a system Asup "Prog_event"

this called by the system

you can setup when it will be called

e.g. program start / end

or when reset is actuated.

in Prog_event.SPF you write

....

PROG_EVENT.SPF

IF ($ P_PROG_EVENT == 3); RESET

$ A_OUT [1] = 0

ENDIF

......

Thanks!