Resetting a SFC program

[waus 0]

Hello, I'm building a program for a FX1N PLC with 4 SFC programs in four different tasks. One SFC progam in a task. Now I want to reset a single SFC (so that it starts from the initial step) from a task other then the ones running a SFC program. I'm programming it with GX IEC Developer 6.01 ES2. I'm aware of the existens of a variable with !RESET! as comment but when i declare it as a global var and set this var, it will reset all the SFC programs so that's not an option. I also tried resetting the state coils of the SFC I want to reset, but then I get a compiler error with the message "Access to system adresses is denied" so that doesn't work either. Does anyone know how I can do this?

[waus 0]

doesn't anybody know? Or is it a really stupid question?

[waynes 8]

waus, Your questionis valid. I have personally no experience programming in SFC in GX IEC. I did check out the !RESET! address, but this is only described as emergency stop of all SFC programs. If it maybe possible to add a parallel branch which always executes. When your "exit" conditon occurs, jump to the end block, which in turn should call up the initial step??? Don't know if what I'm saying (typing) makes sense? I am sure there are experts on SFC here which will assist you. Regards, WayneS

[Colin Carpenter 10]

Sorry, can't help. Have never needed to or wanted to programme in SFC. Stepladder (STL) no probelm, but not SFC

[Crossbow 295]

GX IEC Developer is not actively marketed here in the US, since use of IEC programming is not that widespread here. I've never had a chance to work with it. Sorry.

[cauchy 0]

Hi waus Im using GX Developer. but I don't know differences betwen GX and GX IEC. Im using zrst ?nstruction.Firstly I build a general Control near the SFC blocks which is writing in ladder.And for example Im writing -||--------------[ZRST S0 S100] this instruction is resetting the first 100 steps

[waus 0]

hey cauchy, I tried the zrst instruction in a ladder diagram, but then I get the message "Access to system adresses is denied" like I said in my start post. What do you mean with "I build a general Control near the SFC blocks"?

[waynes 8]

waus, Post your program for us. Maybe one of us will be able to figure out a way to do what you require??

[cauchy 0]

I ve post an example about blocks.There are 2 blocks. One of them is SFC and other is ladder. Ladder is General Control. Im using ZRST instruction in this ladder and its resetting SFC's steps. general_control.bmp