YSI IQ S ENSOR N ET System 182 - Manual (Page 117)

System 182 Outputs
6 - 27 ba76022e01 12/2011
6.5.3 PID controller
Function With the PID controller function, you can use an output as a controller
output. The controller can be configured as a Proportional controller
with a switchable Integral and Derivative controller part (PID controller).
The control mode of the PID controller is described by the following
equation:
with:
The adjustable control parameters are x
nominal
, I
0
, X
p
, I
min
, I
max
, ti
and T
d
(see setting table on page 6-30).
I
Controller
Current at the controller output at time t
I
0
Current at output if x
actual
= x
nominal
K Gain
X
p
Proportional band
x
e
Error signal
x
actual
Actual value (current measured value)
x
nom
Nominal value
ti Integral control part
td Derivative control part
t Time
I
min
Lower current limitation
I
max
Upper current limitation






+ + + =

dt
dx
T dt x
T
1
x K I I e
d e
i
e 0 Controller
p
min max
X
I I
K
−
=
actual nom e
x x x − =
max Controller min
I I I ≤ ≤