Introduction
A coil is an LD element which transfers the status of the horizontal link on the left side, unchanged, to the horizontal link on the right side. The status is stored in the respective Boolean actual parameter.
Normally, coils follow contacts or FFBs, but they can also be followed by contacts.
Coils take up one cell.
The following are permitted as actual parameters:
Boolean variables
Boolean addresses (topological addresses or symbolic addresses)
Coil Types
The following coils are available:
Designation |
Representation |
Description |
|---|---|---|
Coil |
|
With coils, the status of the left link is transferred to the relevant Boolean actual parameter (indicated by xxx) and the right link. |
Negated coil |
|
With negated coils, the status of the left link is copied onto the right link. The inverted status of the left link is copied to the relevant Boolean actual parameter (indicated by xxx). If the left link is OFF, then the right link will also be OFF and the relevant Boolean actual parameter will be ON. |
Coil for detecting positive transitions |
|
With coils that detect positive transitions, the status of the left link is copied onto the right link. The relevant actual parameter of data type EBOOL (indicated by xxx) is 1 for a program cycle, if a transition of the left link from 0 to 1 is made. Also see Edge Recognition. |
Coil for detecting negative transitions |
|
With coils that detect negative transitions, the status of the left link is copied onto the right link. The relevant actual Boolean parameter (indicated by xxx) is 1 for a program cycle, if a transition of the left link from 1 to 0 is made. Also see Edge Recognition. |
Set coil |
|
With set coils, the status of the left link is copied onto the right link. The relevant Boolean actual parameter (indicated by xxx) is set to ON if the left link has a status of ON, otherwise it remains unchanged. The relevant Boolean actual parameter can be reset through the reset coil. Also see Edge Recognition. |
Reset coil |
|
With reset coils, the status of the left link is copied onto the right link. The relevant Boolean actual parameter (indicated by xxx) is set to OFF if the left link has a status of ON, otherwise it remains unchanged. The relevant Boolean actual parameter can be set through the set coil. Also see Edge Recognition. |
Halt coil |
|
With halt coils, if the status of the left link is 1, the program execution is stopped immediately (With halt coils the status of the left link is not copied to the right link.). Sets the CPU to HALT mode. |
Call coil |
|
With call coils, the status of the left link is copied to the right link. If the status of the left link is ON then the respective sub-program (indicated by xxx) is called. The subroutine to be called must be located in the same task as the calling LD section. Subroutines can also be called from within subroutines. Subroutines are a supplement to IEC 61131-3 and must be enabled explicitly. In SFC action sections, call coils (subroutine calls) are only allowed when Multitoken Operation is enabled. |
