Coils in LD
According to →IEC-standard: A coil copies the state of the link on its left to the link on its right without modification and it stores an appropriate function of the state or transition of the left link into the associated Boolean →variable.
See under "Link elements (lines) and their states in LD" for more information about the state of links.
Neuron Power Engineer provides the following types of coils (depending on the →POU type)::
Name |
Symbol |
Meaning |
---|---|---|
Coil |
|
The state of the left link is copied to the associated Boolean variable (= |
Negated coil |
|
The state of the left link is copied to the right link. The inverse of the state of the left link is copied to the associated Boolean variable (= |
Set latch coil |
|
The associated Boolean variable (= |
Reset latch coil |
|
The associated Boolean variable (= |
Positive transition sensing coil |
|
The state of the associated Boolean variable (= This coil is not available within a →function. |
Negative transition sensing coil |
|
The state of the associated Boolean variable (= This coil is not available within a →function. |
Representation
Symbolic representation:
Each coil provides 3 input fields above the coil symbol:
-
Description (=
[Description]
in the upper illustration): Here you are able to enter a description for the coil. If you do not enter any text, this field is hidden. Only when you position the mouse pointer over the coil, the field becomes visible so that you are able to enter a text. -
Tag (=
[Tag]
in the upper illustration): If you do not enter any text, this field is hidden. Only when you position the mouse pointer over the coil, the field becomes visible so that you are able to enter a text. -
Associated variable (=
Var1
in the upper illustration): Here you are able to associate a variable to the coil. By default, theENO
output is entered as the associated variable.
Example for a rung with 2 contacts and one coil: