Hello

I'm working on a project where I must get an object to the desired position. I have no technology module at my disposal so I'm using a regular DI module for counting the encoder signals.

The module picks up every signal, but I'm having trouble to filter out the direction for example, encoder signal A before B means count up, B before A count down. I know the HSC has this function but it's not compatible with a regular input module. Is there any other function I could use to solve my problem?

Buying a counter module is not an option for this time being.

Hardware: S7-1511, SM521 DI 16x24 HF, Sinamics G120C, KTP 400 comfort panel, incremental encoder, motor @ 1380 rpm.

Thanks in advance

Jeff Casagrande

Google is your friend.  I found several examples of code by searching for "determine direction of encoder".  I really must caution that this is NOT the way to do this and will lead to reliability problems.  You really do need an encoder input card.  The DI's are too slow and are updated at the end of your cyclical tasks so are therefore non-deterministic.

 Thank you for your answer. 

Yes I know that card is the best solution, but working on my final project for school and this is the only card available

Good luck.  You will end up writing your own position regulator and your own interpolator.  Are you sure you can't free up some beer money?  Sell some blood?  Thinking of all the other things I did in university to get money.

You could sell your S7 1500 and buy an S7 1200, which has HSC inputs and a position controller AND have money left over to buy MORE BEER!

Jeff Casagrande

Good luck.  You will end up writing your own position regulator and your own interpolator.  Are you sure you can't free up some beer money?  Sell some blood?  Thinking of all the other things I did in university to get money.

You could sell your S7 1500 and buy an S7 1200, which has HSC inputs and a position controller AND have money left over to buy MORE BEER!

 Time is not a problem! The S7-1500 let's me control the drive more easy over profinet, so i'll opt for this one! I'll always have money for beer, no matter what!