kevinlin_5

Hello, Everyone,

I'm new to Siemens PLC. Now I encountered a problem with the INC command. When the INC block was enabled, Tag_InOut of the block was kept on increasing and the increase number is more than one. According to the manual, it was supposed to increment by one each time when it was enabled. So can anybody tell me where the problem is?

Thanks.

Hi.

The INC instruction will keep increasing the value while the enable input is true. You can use a positive edge detection ---| P |--- to force the instruction to execute only once.

Also note.. overlapping memory bits (Mx.y overlapping with MWxx) regularly cause problems for guys newly starting with PLCs.

I would suggest if you still have issues, add a screen shot with you next post to show how you are using the instruction and which memory area you used.

Greetings.
w