Example Recipes

This section demonstrates typical automation tasks. These examples combine functions and blocks into complete programs, providing practical templates that can easily be adapted.

Blinking Light (TON + NOT)

Goal: A light blinks at a 1‑second interval.
Blocks: TON, NOT.

PROGRAM  
    DIM T AS TON  
    DIM led AS BOOL = FALSE  
    T(IN = TRUE, PT = T#1000ms)  
    IF T.Q THEN  
        led = NOT led  
        T(IN = FALSE, PT = T#1000ms)  
    END IF  
    PRINT led  
END PROGRAM

Staircase Lighting (TOF)

Goal: Light remains on for 30 seconds after button press.
Blocks: TOF.

PROGRAM  
    DIM T AS TOF  
    DIM button AS BOOL = TRUE  'Value could come e.g. from an Input %I0
    T(IN = button, PT = T#30s)  
    PRINT T.Q  
END PROGRAM

Pulse Counter (CTU)

Goal: Each button press increments a counter; after 5 pulses print “Done”.
Blocks: CTU.

PROGRAM  
    DIM C AS CTU  
    DIM button AS BOOL = TRUE  'Value could come e.g. from an Input %I0
    C(CU = button, PV = 5)  
    PRINT "Count=", C.CV, " Done=", C.Q  
END PROGRAM

Edge‑Triggered Counting (R_TRIG + CTU)

Goal: Count only rising edges, not static signals.
Blocks: R_TRIG, CTU.

PROGRAM  
    DIM F AS R_TRIG  
    DIM C AS CTU  
    DIM clk AS BOOL = TRUE   'Value could come e.g. from an Input %I0
    F(CLK = clk)  
    IF F.Q THEN  
        C(CU = TRUE, PV = 3)  
    END IF  
    PRINT C.CV, C.Q  
END PROGRAM

Temperature Limiting (LIMIT)

Goal: Clamp temperature to range 0‑100 °C and issue a message if exceeded.
Blocks: LIMIT, IF.

PROGRAM  
    DIM temp AS INT = 120  
    DIM safe AS DINT  
    safe = LIMIT(0,temp,100)  
    PRINT safe  
    IF temp > 100 THEN  
        PRINT "Alarm: Overtemperature"  
    END IF  
END PROGRAM

Exercises with Solutions

Task 1: Blinking light with 2‑second interval.

PROGRAM  
    DIM T AS TON  
    DIM led AS BOOL = FALSE  
    T(IN = TRUE, PT = T#2000ms)  
    IF T.Q THEN  
        led = NOT led  
        T(IN = FALSE, PT = T#2000ms)  
    END IF  
    PRINT led  
END PROGRAM

Task 2: Staircase light with 10‑second timeout.

PROGRAM  
    DIM T AS TOF  
    DIM button AS BOOL = TRUE   'Value could come e.g. from an Input %I0
    T(IN = button, PT = T#10s)  
    PRINT T.Q  
END PROGRAM

Task 3: Counter with threshold 3, print “Alarm” when triggered.

PROGRAM  
    DIM C AS CTU  
    DIM button AS BOOL = TRUE  'Value could come e.g. from an Input %I0 
    C(CU = button, PV = 3)  
    IF C.Q THEN  
        PRINT "Alarm"  
    END IF  
END PROGRAM