A function block groups an algorithm and a set of private data. It has inputs and outputs. - Hysteresis detection.
Inputs
XIN1 : REAL First input signal
XIN2 : REAL Second input signal
EPS : REAL Hysterisis
Outputs
Q : BOOL Detected hysteresis: TRUE if XIN1 becomes greater than XIN2+EPS and is not yet below XIN2-EPS
Remarks
The hysteresis is detected on the difference of XIN1 and XIN2 signals. In FFLD language, the input rung (EN) is used for enabling the block. The output rung is the Q output.
ST Language
(* MyHyst is a declared instance of HYSTER function block *)
MyHyst (XIN1, XIN2, EPS);
Q := MyHyst.Q;
FBD Language
FFLD Language
(* The block is not called if EN is FALSE *)
IL Language:
(* MyHyst is a declared instance of HYSTER function block *)
Op1: CAL MyHyst (XIN1, XIN2, EPS)
FFLD MyHyst.Q
ST "Structured text"
A high-level language that is block structured and syntactically resembles Pascal Q
See also
