Eaton ELC-PB, Руководство по программированию

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3 . I n s t r u c t i o n S e t
M N050 03003E F or mo re infor ma tio n vi sit:
w w w. e a t o n . c o m
3-261
G(s)
S
1/S
1/K
I
K
D
+
+
+
PID operation is within dotted area
P
+
1/K
y
This equation is exclusively designed for temperature control. Therefore, when the
sampling time (T
S
) is set to 4 seconds (K400), the range of output value (MV) will be K0 ~
K4,000 and the cycle time of the GPWM instruction used together has to be set as 4 seconds
(K4000) as well.
y
Auto tuning is available by, selecting K3 (auto-tuning). After all the parameters are
adjusted (the control direction will be automatically set as K4), parameters can be modified
based on the adjusted results.
3. When control mode (
S
3
+4) is selected as K10:
y
S
3
+2 (K
I
) and
S
3
+3 (K
D
) in this mode will be switched to parameter settings of Integral
time constant (T
I
) and Derivative time constant (T
D
).
y
When the output value (MV) reaches the upper bound, the accumulated integral value
will not increase. Also, when MV reaches the lower bound, the accumulated integral value will
not decrease.
y
The equation for this mode will be:
( ) ( ) ( )
⎥
⎦
⎤
⎢
⎣
⎡
+ + × =
∫
t E
dt
d
T dt t E
T
t E K MV
D
I
P
1
Where
( ) ( ) ( )
t PV - t SV t E
=
y
Control diagram:
G(s)
S
1/S
1/T
I
T
D
+
+
+
PID operation is within dotted area
P
+
K