42
3.10.2
Rails
There are two power rails: left rail and right rail. Left rail can be
attached to any of variables excluding output variables and to any kind
of coils. Right rail can be attached only to any kind of coils.
Multiple connections are allowed.
You cannot delete rails.
Figure 60 - Rails
3.10.3
Contact
Contact represents a normally open contact. It is closed whenever its
coil or an input which controls it is energized. (Open contact at rest).
It has 2 pins:
Input pin (left pin), that can be attached to left rail output, output
variable, input-output variable, built-in function block contact or
negated contact.
Output pin (right pin) - can be attached to coil, built-in functions,
contact, negated contact or right rail.
Multiple connections are allowed.
Contact can be created from any BOOL variable.
Figure 61 - Contact
3.10.4
Negated contact
Negated contact represents a normally closed ("not") contact. It is
closed whenever its coil or an input which controls it is not energized.
(Closed contact at rest)
It has 2 pins:
Input pin (left pin) - can be attached to left rail output, output
variable, input-output variable, built-in function block contact or
negated contact.
Output pin (right pin) - can be attached to coil, built-in functions,
contact, negated contact or right rail.
Multiple connections are allowed.
Negated contact can be created from any BOOL variable