IMO Precision Controls K7 Series User Manual page 91

Chapter 7 Usage of Various Functions
Fig. 2.2 When the proportional constant (Kp) is large
Fig. 2.3 When the proportional constant (Kp) is small
b) Integral operation (I operation)
(a) With integral operation, the manipulate value (MV) is increased or decreased continuously in accordance time
in order to eliminate the deviation between the SV and PV. When the deviation is very small, the proportional
operation can not produce a proper manipulate value and an offset remains between PV and SV. The integral
operation can eliminate the offset value even the deviation is very small.
The period of the time from when the deviation has occurred in I action to when the MV of I action become
that of P action is called Integration time and represented as Ti.
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