SFC Element ‘Branch’

Symbol

Use branches to program parallel or alternative sequences in the sequential function chart.

For alternative branches, CODESYS processes just one of the branch lines at a time, depending on the preceding transition condition. Parallel branches are processed at the same time.

See also

Parallel branch

For parallel branches, the branch lines must begin and end with steps. Parallel branch lines can contain additional branches.

The horizontal lines before and after the branch are double lines.

Processing in online mode: If the preceding transition (t2 in the example) yields TRUE, then the first steps in all parallel branch lines are active (Step11 and Step21). CODESYS processes the individual branch lines at the same time and the subsequent transition is passed afterwards (t3).

The “Branch<n>” jump marker is added automatically to the horizontal line that indicates the beginning of a branch. You can define this marker as the jump destination.

Please note that you can convert a parallel branch into an alternative branch by clicking Alternative.

See also

Alternative branch

The horizontal line before and after the branch is a single line.

In an alternative branch, the branch lines must begin and end with transitions. The branch lines can contain additional branches.

If the step before the branch is active, then CODESYS passes the first transition of each alternative branch line from left to right. For the first transition that yields TRUE, the associated branch line opens, thus activating the step following the transition.

Please note that you can convert an alternative branch into a parallel branch by clicking Parallel.

See also