Direction determination of the blocks on the conveyour in S7-300?

Hello Everyone,

I am trying to solve this particular problem of determining the direction of the blocks on the conveyour...

Inputs are only proximity switches three in number and they are situated one after another the distance between them is greater than the block's length...blocks are arranged on the conveyour having considerable space in between them...

My attempt: I tried to solve this problem without taking time stamps..but I couldn't...I thought after getting the time stamp idea it would be simple.. but I am not able to do it...my doubt is if the conveyour is moving and if all sensors sense at the same time the time stamps would be equal and making me very confused..

Any help is required...I am using S7-300.

Hi

One solution is to put two sensors close together ( less than the lenght of the block . using a rising and falling edge pulse you can determine the 'direction'

Eric

Normally for tracking you would use an encoder or a starwheel arrangement, the starwheel would be fitted on the non-driven shaft and a proximity sensor would pick up the signal.

If you wanted direction you could use two proximities and detect direction from which sensor picks up first.

The PEC's on the conveyor (normally there would only be one) would be a tracking update.

Could you just wait in the software for all the sensors to be clear and then when the first one goes high this would tell you from which direction the boxes were coming from?