Can some translate this to ladder Logic

Helo guys,

New to siemens and STL . Can some one translate this ladder logic. In simatic manager when I change language it doesnt work.

A "G99Oven.ExtBit.19"
A(
A "G99Oven".IntTimer._2.Dn
O "G99Oven.OBits.04"
)
FP "G99Oven.OBits.03"
JNB _B15
AN "G99Oven.OBits.04"
= "G99Oven.OBits.04"
_B15: NOP 0

I don't have a ladder editor here but imagine this:


A normally open contact with G99Oven.ExtBit.19, followed by
A parallel branch (or an OR branch) with G99Oven".IntTimer._2.Dn and "G99Oven.OBits.04", followed by
A positive flank detection (OSR in Allen Bradley)


If the above is 1, the processor will then invert bit "G99Oven.OBits.04" (makes it 1 if 0 and vice versa).

If instead it's 0, then it jumps to the line _B15: NOP 0


Makes sense?

As I see it, if the code before the jump to _B15 transitions FALSE to TRUE, then
"G99Oven.OBits.04" will alternate.
Because of the jump, this code wont convert to LAD.
You can create something similar by splitting into 2 LAD networks with JMP and LABEL instructions.

Alternative implementation using S/R coils:

cardosocea said:

A normally open contact with G99Oven.ExtBit.19, followed by
A parallel branch (or an OR branch) with G99Oven".IntTimer._2.Dn and "G99Oven.OBits.04", followed by
A positive flank detection (OSR in Allen Bradley)


If the above is 1, the processor will then invert bit "G99Oven.OBits.04" (makes it 1 if 0 and vice versa).

If instead it's 0, then it jumps to the line _B15: NOP 0

Click to expand...

I think this implements the description above; I assumed the flank detection (one-shot) result goes into G99Oven.OBits.03:


Sorry about the output branches on the first rung: that should be a rising-edge instruction, but I don't know the shorthand for a one-shot in Siemens off the top of my head, and I am too lazy to look it up ; I think I did it right; os03sto is the one-shot storage.

The last rung is a flip-flop clocked by the .OBits.03 one-shot.


I dropped the G99Oven prefix; if the tag starts with a "." then add it back.


The two rungs could be merged into one, but it is cleaner this way, IMNSHO.

drbitboy said:

...
The two rungs could be merged into one, but it is cleaner this way, IMNSHO.

Click to expand...

This is wrong: it has to be two rungs; the second rung could become a branch in parallel with the first, but that is not what I meant.