leo (Customer) asked a question.
Productivity shift registar
Hi I am new to productivity plc. I am trying to setup a shift click register, I need to look for a a missing hole on a strip on a punch press. There is a sensor to look for the hole when the strip has stopped feeding. 4 strokes of the press brings thepart to the cuttoff station, I will have a diverter to kick out the bad part. I have done this with the click shift register It has only 3 inputs,data,clock and reset and data and how many steps before kick ouit with the c register(c1 to c4). How do I set up the productivityto do the same thing.
Thank you and happy holidays
Hi @leo (Customer)
The SFR (Shift/Rotate Bits) instruction is used to create a shift register in any of the productivity controllers.
Call up the instruction and set the input and output to the same register. I am using a 32-bit output called Shift.Output. The "bit to shift in" will indicate the input to the shift register.
In our example, we are using the shift left option. The condition on the rung will determine when to shift the bits in the output. In my case, I am using the first input to shift the bits.
When the fifth bit in the shift output is on then the first bit on the output will turn on.
Call up the Data View window to monitor this shift register in the simulator.
Here is a video to demonstrate:
https://youtu.be/OgcagnbJ6is
I hope this helps you out.
Regards,
Garry
https://accautomation.ca/series/productivity-1000-plc/
Sounds easy enough. Make your boolean array with at least 4 columns since that is what you have from sensor to pickoff. I would have a rung that has a contact for when the machine stops the shift/rotate bits instruction becomes active that scan (select one shot on the shift/rotate bits). If the sensor is off (seeing a hole) then it would shift an "off" into the array, if the sensor is on (not seeing a hole) then it would shift and "on" into the array. This would shift the sensor reading over each time the machine stops for a cycle. So when the cycle starts again your pickoff location looks at the 4th column of the array to see where it says on/off and engages the diverter or not accordingly.
One thing I like to do is mount indicator LED lights on the back of my machine when doing something like this, and have each light correspond to a column of the array. If off, the LED is off, if the column has an "on" in it, the LED is on attached to that column. This way you can see the bad product location easily and watch it travel down the machine.