kevinlin_5

Dear all,

I am currently working on a project with an incremental encoder, when the encoder is rotating, I can get the value from High Speed Counter in my plc program. In my configuration, encoder clockwise rotating generates an increasing value, counter-clockwise rotation generates a decreasing value. 

Now my question is, besides of use program to compare the count value of the high speed counter, is there any other way I can use to detect the rotating direction of the encoder? Are there any tags in the high speed counter parameter can do this? 

Thanks.

I am assuming the S7-1200 PLC.

The way you are thinking, is the way I prefer.

There is however interrupts that you can configure as part of the hardware configuration, that can indicate a change of direction. That is handy if you need to know when something changes, at the moment it changes.

w

If you connect up the A&B phases of the encoder, the PLC will know the direction at all times.  The count does not go down if it moves backwards or forwards.  It just counts pulses for single phase input of an encoder.  If you have an ABSOLUTE encoder, you get increase and decrease values, and often they are profibus/profinet type devices - which are must easier to work with (my opinion).

kevinlin_5

Dear all,

I am currently working on a project with an incremental encoder, when the encoder is rotating, I can get the value from High Speed Counter in my plc program. In my configuration, encoder clockwise rotating generates an increasing value, counter-clockwise rotation generates a decreasing value. 

Now my question is, besides of use program to compare the count value of the high speed counter, is there any other way I can use to detect the rotating direction of the encoder? Are there any tags in the high speed counter parameter can do this? 

Thanks.