comparator problem

dannyt

Member
D
Join Date
Oct 2008
Location
Brasov
Posts
4
Hi guys,

I'm trying to make a program in S7 Manager and I have an issue with a comparator.
I need to compare the int variable "C" with "3", but the comparator block doesn't allow me to insert the C variable. I've added it as a symbol but I don't know what to do in order to make the comparison.šŸ™ƒ

Can someone help me?

Thanks,
Dan.
 
dannyt said:
Hi guys,

I'm trying to make a program in S7 Manager and I have an issue with a comparator.
I need to compare the int variable "C" with "3", but the comparator block doesn't allow me to insert the C variable. I've added it as a symbol but I don't know what to do in order to make the comparison.šŸ™ƒ

Can someone help me?

Thanks,
Dan.
Click to expand...
Are you using the "Integer" comparator to begin with?
If you don't that's your problem.
Use CMP_I= or CPM_I< and such, not sure wht you are trying to accomplish.
If you do type in your symbol as a first value and ONLY type "3" as your second value.
I do not have Step7 on this PC, going by memory.
 
Last edited:
Hi and thanks for the quick reply,

I've added a screenshot with what I'm trying to do.

"c" is already added as a counter symbol.

Basically I'm trying to see if the counter is smaller then or equal to 2.

I hope this helps.

Dan.
 
You cannot use a counter in a compare. Move the count to a temp integer and then do the comparison. Turn type checking off.

cmp0099.JPG
 
You've declared it as a word, not a counter. If you are performing arithmetic then declare it as an integer (INT). You must save the symbols file for it to take effect. When typing in a symbol name in the ladder editor, you need to put it in double quotes
 
Last edited:

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