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Error number illegal of Rise/Fall element

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I'm writing to you because I'm having a problem compiling my program on Visilogic. When I compile, I get an error such as: Illegal number of rising or falling edges.
So I'd like to know if there's a trick or method to quickly identify where my error is.

Thank you very much 
Good day

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There are limits to the number of     -|P|-    and   -|N|-   that can be used in a program - They also take up more processing time than a  -| |-  contact.

  Aslo Review the Help Topics       Contacts        Postive Transition Contact(Rise)    for further information.

If you have several    -|P|-  assigned to a single MB  say MB11   - say you use it 6 times.

  then do this       -|P|-  -(  )-      MB11 turns on MB12     do this at the start of the ladder

  Now use     -|   |-   MB12      in place of the MB11   -- does the same thing   the leading edge pulse.( also saves scan processing time)

  Also Examine your program as to why you are using so many of the     -|P|-    and   -|N|-    in your program.

 You can also upload your program and some one can do a review and provide some  suggestions to reduce them 



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  • MVP 2023
1 hour ago, DanT said:

There are limits to the number of     -|P|-    and   -|N|-   that can be used in a program

As Dan correctly points out, transition contacts are limited in your PLC program. The reason for this is that in order for the transition contact to work properly, memory must be set aside to "remember" the state of the bit operand on the previous scan. The size of the block of memory set aside for transition contacts varies by PLC model from 256 to 1024, but sometimes the actual compiled number of transition contacts is greater than what you can count in ladder due to the result of the STL translation from ladder that actually gets compiled.

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