MKS 640A/641A, Manual, Page: 52 / 88

Chapter Three: Overview Tuning the 640 Series Pressure Controller
39
Controller Response with Increased P Term
Increasing the P term to 1 while holding the I term at 0 yields:
P = 1
I = 0
Settling Time
Settling Time
Set Point
Signal
4
2
6
8
Pr
e
s
su
re
, (T
o
rr)
Time
Figure 18: Controller Response with Increased P Term
The controller responds much faster, however some overshoot occurs.
Controller Response with Increased I Term
Reducing the P term to 0 and increasing the I term to 5 yields:
P = 0
I = 5
Settling Time Settling Time
Set Point
Signal
4
2
6
8
Pr
e
s
su
re
, (T
o
rr)
Time
Figure 19: Controller Response with Increased I Term
The response of the controller is quick, yet no overshoot occurs. This combination of P term and
I term yields the best control for our example system.