P_LLS - Don't understand how it swaps beyond 2 pumps

[jakeparsons03]

I have been reading everything I can find on the P_LLS the last 2 days but I am still having trouble understanding how the P_LLS swaps beyond 2 pumps. I understand that you create a array tag for the amount of motors you have and tie it to the "Ref Motors" tag in the LLS however the Ref Motors tag only has 2 array spots. How do I tie my third, fourth or fifth pump to the LLS?

 

[cardosocea]

What do you mean by "only has two spots"?? You can change the array size.

 

[DarrylR]

https://literature.rockwellautomation.com/idc/groups/literature/documents/rm/proces-rm013_-en-p.pdf

If you haven't seen it, Chapter 2 (page 107) has good information.

 

[jakeparsons03]

What do you mean by "only has two spots"?? You can change the array size.

The P_LLS "Ref_Motors" tag array accepts only 2 motors, its of datatype P_LLS_Motor[2]. So even if I tie a 5 motor array tag, say of datatype P_LLS_Motor[5], to the "Ref_Motors" tag it will only take the first 2.

 

[jakeparsons03]

https://literature.rockwellautomation.com/idc/groups/literature/documents/rm/proces-rm013_-en-p.pdf

If you haven't seen it, Chapter 2 (page 107) has good information.

Yeah I have read through it but doesn't really explain how to tie in any motors past the first 2. I am sure it does, I just don't see it.

 

[Cheeseface]

Did you do this?

P_LLS.Cfg_NumMotors := 3;
P_LLS.Cfg_MaxDemand := 2;
P_LLS.Cfg_MinDemand := 0;
P_LLS_Motors[xx].Sts_Available := 1;

 

[Cheeseface]

The P_LLS "Ref_Motors" tag array accepts only 2 motors, its of datatype P_LLS_Motor[2]. So even if I tie a 5 motor array tag, say of datatype P_LLS_Motor[5], to the "Ref_Motors" tag it will only take the first 2.

This isn't true btw. Arrays as InOut parameters behave somewhat like C arrays. For my AOIs I prefer to specify ArrayType[1] -- it doesn't allow [0] -- to make it more clear, but inside the AOI must use SIZE to determine the safe access boundary.

 

[jakeparsons03]

This isn't true btw. Arrays as InOut parameters behave somewhat like C arrays. For my AOIs I prefer to specify ArrayType[1] -- it doesn't allow [0] -- to make it more clear, but inside the AOI must use SIZE to determine the safe access boundary.

So the [1] array size essentially just makes it an array but it uses your size that you choose as the actual array size within the P_LLS itself?

 

[Cheeseface]

Right

 

[jakeparsons03]

Right

Gotcha, that was my hang up. I understand now, thanks!