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franciscoazzad · Junior Joined: 19 Apr 2022 Posts: 2

Hello to everyone. Nice to meet you all. How are you? I hope you are doing well.

I’m developing a program with the purpose of make something similar to a pulse train in the output. However, sometimes I need the output to be a “positive” pulse and sometimes a “negative” one. By positive and negative I mean the polarity in relation to the pulse train source.

I’m trying to use a pair of bits in order to switch between the two choices of polarities. I attach a simplified version of the ladder diagram I’ve made. When I thought about the logic, it seemed logical to me, however, it isn’t working as supposed.

SM0.4 is a pulse train source. According to the software manual, it is a pulse train with 50% duty cycle and a cycle time of 2 s. That it to say it says at TRUE for one second and return to FALSE for another second. I assign the value of that variable bit to the M0.0 memory bit. I get the negative version of the pulse train logically negating it in the Network #2.

I assign the value of two inputs, I0.0 and I0.1, to other two memory bits, M0.1 and M0.2.

· When both inputs are in a FALSE state, the output stays FALSE, disregarding the state of SM0.4. (Case #1)

· When I0.0 is TRUE, M0.1 is TRUE. However, Q0.0 stays at FALSE no matter SM0.4 is TRUE or FALSE. I attach a pair of pictures. (Case #2)

· On the other side, when I0.1 is TRUE, M0.2 is TRUE. In this case, the output shows the correct behavior. It is the negated version of the pulse train source. (Case #3)

Has any of you experienced something similar? Is there a better way to execute my purpose?

I’m not executing the program, just simulating it with KincoBuilder from Kinco. However, it has always worked fine for me.

Thanks for you attention. I look forward for your responses.

Kind regards!

Case #1
[url=http://www.99poze.ro/p/8f811433a885d01ebcc2be267818258d.jpg] Output polarity selection Output polarity selection

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Case #2
[url=http://www.99poze.ro/p/867bc172839600e6168139d41d630297.jpg] Output polarity selection Output polarity selection

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Case #3
[url=http://www.99poze.ro/p/199fa30ac8a6d47bf51c3989748fde3d.jpg] Output polarity selection Output polarity selection

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huyndog · Junior Joined: 29 Mar 2022 Posts: 1

franciscoazzad · Junior Joined: 19 Apr 2022 Posts: 2

Hello!

I was using KincoBuilder, the programming software from Kinco.

Thanks for your response. I could solve the issue introducing some OR operations. I was involved in something called the "double coil syndrom''.

Regards!