It seems because an other line reset the %M13.
The visualisation of the variable is normally done at the end of the cycle, That's why you can see a false result on an equation which seems to be true. The %M13 is used in the other lines and is reset by the other logic.
When you work in Ladder a very good practice is to write the coils only once in the program. It's a continuous flow, so when the coil is written several time only the last write will be used.
The SET, RESET coils may be used instead the direct coil, but the good practice is the same: one equation to set and one equation to reset the coil.
Can u give me a wiring diagram for connecting m221 serial (rj45) to HMI rs485 dp9 comunication. And what will be the setup in HMI program. I am now stuck on this. And Google is confusing me and can't find the accurate one about it
I need it will you please help me?