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Old February 14th, 2020, 09:52 AM   #1
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Kipper is offline
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Using a pointer or condition Don't know what to call this one.

We have a repair hole that carriers come into. As they come in they pass a RFID reader and each carrier has a tag. The repair hole can hold 5 carriers. On my PV I show 5 displays.

If you look at my logic where there is a 0 it will write the carrier ID. How can I make it so it would only write to one location not all of the locations with zeros.

Clear as mud
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Kipp M Koenig
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Old February 14th, 2020, 11:22 AM   #2
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Hi, I'm not a hundred percent, but you may have to check the connection for the numerical displays in your HMI. Assign each display an address from your logic. I don't mean to say you don't know this, but I've made that mistake. Or use some copy instructions in logic and hold out the others in the queue until a new carrier is present. Just a thought.
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Old February 17th, 2020, 01:24 PM   #3
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The way I have handled this in the past is add a latch of the same bit on each of the branches in the selection logic then use normally closed contacts of that bit as conditions on each of the branches. Add a single unlatch after the selection logic. This will insure that only the first detected case will be services in each scan.

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