Float Switch Controlling Output

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AndrewsBrewing
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Float Switch Controlling Output

Post by AndrewsBrewing » Wed Aug 28, 2019 7:37 am

We are trying to kill elements if the fluid level gets below the float switch for any reason. We are having difficulty getting this to work.

Ladder Logic:

The above works fine if we do this.
IF DIN1 (Float Switch) AND PROC2 (process where we are using heating elements) THEN OUT5 (heating element)

It does not work correctly when we do this.
IF DIN1 (Float Switch) AND REG2 (asserted on a state where we are using heating elements) THEN OUT5 (heating element)

The OUT5 is no longer controlled by the DIN1 while in that state which asserts REG2.

I hope I was clear in explaining this.

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AndrewsBrewing
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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Tue Sep 03, 2019 7:40 am

...anybody?

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oakbarn
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Re: Float Switch Controlling Output

Post by oakbarn » Wed Sep 04, 2019 11:21 am

Did you try reversing the REG to NC? I know I had some issues with the way Ladder Logic and the way REGs work a long time ago. I no longer use that so I am going from memory. It seems counter intuitive at the time.

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JonW
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Re: Float Switch Controlling Output

Post by JonW » Wed Sep 04, 2019 6:25 pm

Can you post a screenshot of your ladder logic?

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AndrewsBrewing
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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Thu Sep 05, 2019 4:30 am

Annotation 2019-09-05 072720.png
Annotation 2019-09-05 072720.png (7.87 KiB) Viewed 120 times
DIN1 (Float Switch)
REG2 (asserted on a state where we are using heating elements)
OUT5 (heating element)

I'll try Oakbarn's suggestion this morning.

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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Thu Sep 05, 2019 5:13 am

Oakbarn I tried changing the gender on the REG this morning and that is not the solution. Thank you though

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JonW
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Re: Float Switch Controlling Output

Post by JonW » Thu Sep 05, 2019 9:02 pm

I was looking to see all of your ladder logic. Precedence and grouping can affect your results.

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AndrewsBrewing
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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Fri Sep 06, 2019 3:22 am

Here you go. The first two were me playing with another float sensor
Annotation 2019-09-06 062110.png
Annotation 2019-09-06 062110.png (24.1 KiB) Viewed 101 times

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AndrewsBrewing
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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Fri Sep 13, 2019 1:10 pm

For what it's worth, this doesn't work for me either. (Removing all the other rungs.)
Annotation 2019-09-13 160023.png
Annotation 2019-09-13 160023.png (11.91 KiB) Viewed 75 times

Neither does this
Annotation 2019-09-13 160055.png
Annotation 2019-09-13 160055.png (10.94 KiB) Viewed 75 times

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AndrewsBrewing
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Re: Float Switch Controlling Output

Post by AndrewsBrewing » Fri Sep 13, 2019 1:11 pm

Here are screen shots for reference
Annotation 2019-09-13 160224.png
Annotation 2019-09-13 160224.png (15.33 KiB) Viewed 75 times
Annotation 2019-09-13 160159.png
Annotation 2019-09-13 160159.png (24.65 KiB) Viewed 75 times
Annotation 2019-09-13 160124.png
Annotation 2019-09-13 160124.png (41.92 KiB) Viewed 75 times

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