lib/pid_st.txt
author greg
Wed, 28 Oct 2009 13:50:56 +0100
changeset 213 f386d870e8e4
parent 192 c6c2a3d487ac
child 276 1679f514f38a
permissions -rwxr-xr-x
Fix some bug in debian packages
192
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     1
 FUNCTION_BLOCK PID
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     2
   VAR_INPUT
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     3
     AUTO : BOOL ;        (* 0 - manual , 1 - automatic *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     4
     PV : REAL ;          (* Process variable *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     5
     SP : REAL ;          (* Set point *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     6
     X0 : REAL ;          (* Manual output adjustment - *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     7
                          (* Typically from transfer station *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     8
     KP : REAL ;          (* Proportionality constant *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
     9
     TR : REAL ;          (* Reset time *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    10
     TD : REAL ;          (* Derivative time constant *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    11
     CYCLE : TIME ;       (* Sampling period *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    12
   END_VAR
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    13
   VAR_OUTPUT XOUT : REAL; END_VAR
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    14
   VAR ERROR : REAL ;        (* PV - SP *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    15
       ITERM : INTEGRAL ;    (* FB for integral term  *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    16
       DTERM : DERIVATIVE ;  (* FB for derivative term *)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    17
   END_VAR
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    18
   ERROR := PV - SP ;
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    19
   (*** Adjust ITERM so that XOUT := X0 when AUTO = 0 ***)
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    20
   ITERM (RUN := AUTO, R1 := NOT AUTO, XIN := ERROR,
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    21
          X0 := TR * (X0 - ERROR), CYCLE := CYCLE) ;
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    22
   DTERM (RUN := AUTO, XIN := ERROR, CYCLE := CYCLE) ;
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    23
   XOUT := KP * (ERROR + ITERM.XOUT/TR + DTERM.XOUT*TD) ;
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    24
 END_FUNCTION_BLOCK
c6c2a3d487ac Adding inclusion of function blocks defined in AnnexF into library blocks
lbessard
parents:
diff changeset
    25