En
gl
is
h (
G
B)
48
15.2.8 Three-position step controller
Application
•
Upward control direction of chlorine
concentration using chlorine bleaching leach or
chlorine gas.
•
Control of dosing pump or gas dosing unit using
servomotor.
Description
•
The actual value of the required chlorine
concentration exceeds the setpoint:
– Set the servomotor of the dosing pump or
chlorine gas dosing unit to minimum.
•
The actual value of the required chlorine
concentration falls below the setpoint:
– With reduced chlorine concentration:
The servomotor moves in direction of the
increased dosing capacity.
– With increased chlorine concentration:
The servomotor moves in direction of the
decreased dosing capacity.
Fig. 65
Three-position step controller
Parameter settings
TM
03
71
1
8
1
6
1
3
Min.
Max.
Min.
Max.
Min.
Max.
SP 1
Chlorine
concentration
Deviation from
setpoint
Position of the servomotor
SP 1
Required chlorine concentration, e.g. 38 %.
Pulse frequency for SP 1
0
SP 2
-
*)
Pulse frequency for SP 2
-
X
p
e.g. 100 %
• Higher setting results in smaller control steps.
• Lower setting results in larger control steps.
T
n
e.g. 300 sec
• Higher setting results in slower control.
• Lower setting results in faster control.
T
v
0
Hysteresis
e.g. 1 %
Interpulse period
-
Actuating time
Runtime of servomotor between minimum and maximum
capacity (0-100 % dosing capacity), e.g. 90 sec.
Minimum pulse width
≥
0.3 sec
Required code functions
1, 18
Other code functions
As required
*)
"-": without function (no setting required)
