Help on ladder logic

Describe your system and processes, and post your config file.
losco70
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Help on ladder logic

Post by losco70 » Mon Dec 05, 2016 12:02 pm

Hi,
I need some help, better an example to create a ladder logic that set to on outY when outX is off and set to off outY when outX is on.
I want to manage only outX and let the bcs manages the outY
Thank you
Luca

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JonW
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Re: Help on ladder logic

Post by JonW » Mon Dec 05, 2016 1:48 pm

That's a pretty straight forward use for ladder logic. See image below.
Ladder_Out.PNG
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oakbarn
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Re: Help on ladder logic

Post by oakbarn » Mon Dec 05, 2016 3:02 pm

You need to remember that Ladder Logic takes precedence over all other control.

When you do this, you are controlling Out Y ONLY by Out X and nothing else. That means that if your BCS is powered and Out X is Off, Out Y will be ON. There are two ways to turn Out Y off:

Turn on Out X
Unplug the BCS


You can Add Processes and even States (via Registers) to ONLY have Out Y come On if Out X is Off in Process 1 State 1. Unless you limit the logic, you have the condition above. In this, Out Y is Controlled by Out X when you are in Process 1 and Only in State 1.

You can select a Register in the Process Editor. The Register will be asserted when you are IN the State Where the Register is checked. I use these in ladder Logic when I need a control only within a Process and a State.
(I use the Registers 0-7 as State Markers: State 0 = Register 0 and so on).
ll1.png
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losco70
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Re: Help on ladder logic

Post by losco70 » Mon Dec 05, 2016 3:02 pm

Thank you JonW!
If you ever come to Italy I will offer you a beer :)

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Re: Help on ladder logic

Post by losco70 » Mon Dec 05, 2016 3:08 pm

oakbarn wrote:You need to remember that Ladder Logic takes precedence over all other control.

When you do this, you are controlling Out Y ONLY by Out X and nothing else. That means that if your BCS is powered and Out X is Off, Out Y will be ON. There are two ways to turn Out Y off:

Turn on Out X
Unplug the BCS

The 2 output are wired to a 3 position selector (on/off/auto) so for me it's ok that the bcs always control the 2 out. If I need a manual override I just switch the selector.
Thank you

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Re: Help on ladder logic

Post by losco70 » Mon Dec 05, 2016 3:09 pm

There is a beer waiting for you too of course :)

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oakbarn
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Re: Help on ladder logic

Post by oakbarn » Mon Dec 05, 2016 3:17 pm

Mi piace la birra.
Ho vissuto a Roma molti anni fa.
Viaggio in Italia in occasione. :D


Alora...

losco70
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Re: Help on ladder logic

Post by losco70 » Mon Dec 05, 2016 3:28 pm

oakbarn wrote:Mi piace la birra.
Ho vissuto a Roma molti anni fa.
Viaggio in Italia in occasione. :D


Alora...
Wow!
Il tuo italiano è migliore del mio inglese :)
Quando tornerai in Italia sarai mio gradito ospite
Luca

losco70
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Re: Help on ladder logic

Post by losco70 » Thu Nov 02, 2017 9:44 am

Hi,
I need some help: it is possible with ladder logic to use the same DIN to start/stop a process?

example:
push DIN1 --- start process 5
push DIN1 --- stop process 5

Thank you
Luca

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JonW
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Re: Help on ladder logic

Post by JonW » Thu Nov 02, 2017 9:48 am

Yes, with a slight modification. I would use either a push on/push off style button switch or a toggle switch. Your ladder logic is then just like my example in post #2 except you have the din as the input and the proc as the action.

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