Siemens SIPART DR24 - Page 80

1 Technical Description
1.5 Functional Description
1.5.8 Complex Functions (Arithmetic blocks c, d, h)
Manual
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SIP ART DR24 6DR2410
C79000-G7476-C153-03
Frequency response:
ya
xd
=+kp

1 +
1
jω Tn

-D-part
The D--part is added.
Frequency response:
y
D
xd
D
=+kp
jω T
v
1 + jω
T
v
V
v
D General parameters
- Working point Yo for P controller
The working point yo of the P--controller can be set either automatically or as a parame-
ter (onPA).
- Automatic working point (Yo = Auto)
Whenever there is no automatic operation (manual, tracking, safety or blocking opera-
tion) (yz is then active), the working point yo is tracked so that there is a bumpless switch
over to the automatic mode.
yo = ya
-- kp · xdp -- yz
This gives an automatic setting of the working point yo in manual mode:
yo = y
H
-- K
p
(xd
H
)--yzwithxd
H
=w--x
H
If the actual value in manual mode (x
H
) is driven to the desired setpoint (w) by the ap-
propriate manual manipulated variable (y
H
), the working point (yo) is identical to the
manual manipulated variable (y
H
).
yo = y
H
or yo = y
H
+yz
- Set working point (Yo = 0 to 100 %)
The controller operates in all operating modes with the working point set as a permanent
parameter .
- Response threshold AH
The response threshold AH (dead zone element) is circuited after the inputs yz, xd
P
,xd
D
,
xd
I
in the control difference.
--AH
AH
x
d
output
x
d
input
Figure 1--36 Effect of the dead zone element