Hach-Lange SI794 C User Manual - Manual (Page 85)

85
Proportional action Y
P
Setpoint - Meas. value
Measuring range
Y
P
=
* K
C
with:
Y
P
Proportional action
T
R
Reset time [s]
T
D
Rate time [s]
K
C
Controller gain [%]
100 %
50 %
X
w
(Process variables: mS/cm, S/m, SAL)
Co
nt
ro
lle
r
output
Y
K
C
= 500 % K
C
= 200
%
K
C
= 100
%
K
C
= 50
%
MR*0.2 MR*0.4 MR*0.6 MR*0.8 MR
Proportional action (Gradient K
C
[%])
Deviation
Neutral zone (Y=0)
Tolerated deviation from desired value.
With the setting “1 mS/cm” a deviation of ± 0.5 mS/cm
from the desired value does not activate the controller.
Controller equations
Controller output Y = Y
P
+ Y
P
dt + T
D
I action D action
dY
P
dt
P action
1
T
R