S:FS bit won't turn on after power up:
I have an existing program that I had to modify to do something on start up.
One of the conditions for the action is the S:FS bit because it becomes true when the PLC powers up and executes its First Scan.
I have been testing this new piece of code by cycling the power to the machine. Normally, the S:FS bit would be on as soon as I reconnected to the PLC. However, halfway through testing, the S:FS is somehow just not turning on after cycling power.
I've even powered down and left the PLC off for several minutes before powering up, and still it won't turn on.
I also moved it to the main routine, rung 0 to make sure it's the first rung executed.
Anyone experience this before or have any insight as to why it's happening?
I have an existing program that I had to modify to do something on start up.
One of the conditions for the action is the S:FS bit because it becomes true when the PLC powers up and executes its First Scan.
I have been testing this new piece of code by cycling the power to the machine. Normally, the S:FS bit would be on as soon as I reconnected to the PLC. However, halfway through testing, the S:FS is somehow just not turning on after cycling power.
I've even powered down and left the PLC off for several minutes before powering up, and still it won't turn on.
I also moved it to the main routine, rung 0 to make sure it's the first rung executed.
Anyone experience this before or have any insight as to why it's happening?
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