Help on PID (ISA)

Hi experts;
Good day. I attach an image which shows the PID setting. In yellow circle i want to understand what is that and its effect if i change it?
Second i am unable to understand if SP and PV are same it means the error is zero if i used(SP-PV) so
is the CV also zero?
For example i used this setting which shown on image if SP is 8000 and PV also 8000 what is the CV?
and u see in proportional gain 11.18%/% i understand it is the 11.18%of CV/ PV % am i right?
Please help me i am new with GE 90-30.
Thanks in advance
GOD BLESS U ALL

I'm not a 90-30 guy myself but a couple of your questions are generic.

First of all, if you are using the integral term (as you are in this case) you cannot make a specific determination of what the CV is given a value of error. That is because the integral term will be developing a sum any time there is an error. If the error is zero the sum simply doesn't change. That sum is part of the CV. So while it is true that there is no PROPORTIONAL contribution if the error is zero you cannot say the CV will be zero if the error is zero.

Since i'm not a 90-30 guy I may have this wrong but this is how I read the units. The proportional gain is defined in terms of CV output percent per percent ERROR. So in your example, if both SP and PV are at 8000 the PROPORTIONAL output would be 0%. If the error is +5% the PORPORTIONAL portion of the CV would the 55.9%. This would be in addition to whatever the integral sum is.

Keith

Hi;
plz help i mark yellow on image i want to understand if i change these values what happen?