Eaton easyE4 series, Руководство пользователя

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6. Function blocks
6.1 Manufacturer function blocks
6.1.7.6 JC - Conditional jump
General
This function block is only available when using the EDP (easy
Device Programming) programming language.
easyE4 base devices provide 32 conditional jump function blocks,
JC01 through JC32. You can use JC function blocks to branch off for-
ward to an LB jump label function block within the function block dia-
gram and skip several function blocks while doing so.
The JC function block is used in the circuit diagram, while the LB func-
tion block is used in the function block diagram. You can use this
approach to structure a program.
Operating principle
In order for a jump to be executed, function block input EN must have a state of 1.
The jump target is defined using an LB jump label function block.
JC.. and LB.. must always be used in pairs.
When EN = 1, the program jumps forward over one or several function blocks. The next
function block to be processed by the program is the first one following the jump label
LB.. in the function block diagram.
When EN = 0, the next function block that the program processes is the one that you
have added behind JC.. in the function block diagram.
If the associated jump label is not present for an activated jump or is positioned in front
of the jump label (backward jump), the program jumps to the end of the function block
diagram.
In both cases, the function block output will be set to state E1 = 1.
Please note that if there is a timing relay function block that
has been started in the circuit diagram, the time will keep
counting up even if the timing relay is skipped in the function
block diagram with JC..
Display of function blocks in the function block diagram
Active function blocks
During simulation, the function block status display shows a red frame around an activ-
ated function block that is being processed in the program.
An inactive function block that is not being processed, for example, because the enable
coil is set to 0, is shown in a black frame.
The following figure shows the function block JC.. as an example of an active function
block. This functions here as the active jump label.
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easyE4 11/18 MN050009 EN www.eaton.com