BTunnicliff
Member
Hello All,
I am fairly new to programming ladder logic in general and I am looking for a little nudge in the right direction. To give a quick background I have an ME background and just started writing PLC programming for this new company so I have experience with only writing code for one small slitter/rewinder (Thin plastic sheeting).
To give a quick rundown of the project I am working on. The system I am currently working on is a 1769-L33ER AB compact logix controller. I am using the most current version of Studio 5000. The system I am working with is a turret winder that is running thin plastic sheeting, .5 -5 mil. This has a top and bottom turret that will be running at the same time.
My responsibilities: The main speed of the machine will be determined upstream of my program from the main nip drive. I will be able to see this speed but I will not be controlling it. So the rewind portion of this machine has a dancer roller for trimming speed to the rewind shaft. This is supposed to help maintain my tension for my material.
My Questions: On my first slitter/rewinder that I programmed I only controlled the tension with the pressure of the dancer roller, and all the speed matching was done outside of the PLC. (Explained to me buy our electrical guru here: Main nip speed voltage is trimmed by the dancer position which then gives the rewind spindle speed that it should be running. As the roll grows the spindle must slow down to maintain constant line speed.)
So now I want to be able to do this all in the PLC because there are times that I need to give the rewind spindle a different signal than the dancer position. I.E. During turret cutover the empty spindle must be run at line speed which will be different from an empty core, 3.5" OD, to a full roll of 24" OD.
I have looked a lot on this forum for tension control theory and learned a lot, but I am just getting stuck on how to write the actual logic. If anybody has any sample code they don't mind sharing with me it might be able to help me over this hump.
I know this is very long winded, but if anybody can help it would be much appreciated. Please if I am not clear on my description of the system ask me for clarification.
-Brian
I am fairly new to programming ladder logic in general and I am looking for a little nudge in the right direction. To give a quick background I have an ME background and just started writing PLC programming for this new company so I have experience with only writing code for one small slitter/rewinder (Thin plastic sheeting).
To give a quick rundown of the project I am working on. The system I am currently working on is a 1769-L33ER AB compact logix controller. I am using the most current version of Studio 5000. The system I am working with is a turret winder that is running thin plastic sheeting, .5 -5 mil. This has a top and bottom turret that will be running at the same time.
My responsibilities: The main speed of the machine will be determined upstream of my program from the main nip drive. I will be able to see this speed but I will not be controlling it. So the rewind portion of this machine has a dancer roller for trimming speed to the rewind shaft. This is supposed to help maintain my tension for my material.
My Questions: On my first slitter/rewinder that I programmed I only controlled the tension with the pressure of the dancer roller, and all the speed matching was done outside of the PLC. (Explained to me buy our electrical guru here: Main nip speed voltage is trimmed by the dancer position which then gives the rewind spindle speed that it should be running. As the roll grows the spindle must slow down to maintain constant line speed.)
So now I want to be able to do this all in the PLC because there are times that I need to give the rewind spindle a different signal than the dancer position. I.E. During turret cutover the empty spindle must be run at line speed which will be different from an empty core, 3.5" OD, to a full roll of 24" OD.
I have looked a lot on this forum for tension control theory and learned a lot, but I am just getting stuck on how to write the actual logic. If anybody has any sample code they don't mind sharing with me it might be able to help me over this hump.
I know this is very long winded, but if anybody can help it would be much appreciated. Please if I am not clear on my description of the system ask me for clarification.
-Brian