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In EcoStruxure Machine Expert Basic, how do you pulse a bit after a short delay in Ladder Logic?

Published date: 27 September 2019

Issue
How do I write a program in Ladder Logic to turn ON a Boolean (%M2) variable for a short time after a delay triggered by another Boolean variable (%M0)'s rising edge?
Is there an example on how to do this?

Product Line
EcoStruxure Machine Expert Basic (SoMachine Basic) with Modicon M221 PLC

Environment
PLC configuration software in Windows

Resolution
A program can be written comprised of three Variables and three Ladder Logic Rungs.
Please see the example below.

Goal:
Turn on PULSEDBIT for 2 seconds after a 5 second delay after a rising edge (transition from FALSE to TRUE) from BUTTONPRESS.

Variables:
BUTTONPRESS (%M0) - the variable that triggers the sequence on rising edge
TIMERTRIGGER (%M1) - an intermediary variable that turns on the first timer in the program
PULSEDBIT (%M2) - the boolean variable that we wish to turn on for 2s after 5s delay

Rung0: Rising Edge detection latch
    1) Create a Contact -| |- with BUTTONPRESS (%M0) assigned
    2) In parallel with the first Contact, add a second Contact with TIMERTRIGGER (%M1) assigned
    3) To end the ladder Rung, add a Set Coil -(S)- with BUTTONPRESS (%M0) assigned

Rung1: Delay timer
    1) Create a Contact -| |- with TIMERTRIGGER (%M1) assigned.
    2) In series to the contact, add a TON Timer (%TM0).
    3) Mouse over the TON Timer block and change the time to 5 seconds.
    4) To end the ladder Rung, add a Set Coil -(S)- with PULSEDBIT (%M2) assigned - this turns PULSEDBIT to TRUE after the 5s delay

Rung2: Turn ON PULSEDBIT for 2 seconds and  reset all variables to FALSE
    1) Create a Contact -| |- with PULSEDBIT (%M2) assigned.
    2) In series to the contact, add a TON Timer (%TM0).
    3) Mouse over the TON Timer block and change the time to 2 seconds.
    4) To end the ladder Rung, add three parallel Reset Coils -(R)- with each of the three Variables assigned - this will reset all the variables back to FALSE once the timer sequences are completed.
    
The completed project should appear as follows:


Example project (created in EcoStruxure Machine Expert Basic v1.0.0.63163):
"PulsedBitExample.zip" - extract the PulsedBitExample.smbp project file

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