Evoqua WALLACE & TIERNAN SFC, Original Instruction Manual

Page: 71 / 288

SFC
Functions
4.
71
4.5.2.1 Single feed forward with process measurement
This operating mode controls the quantity-proportional dosing of
disinfectants. The single feed forward with process measurement
is only supported with sensor measuring modules with the Process
Control option.
A typical application is simple flow-controlled potable water
chlorination, as shown in the following figure.
Picture 11 Process measurement with single feed forward.
Required module configuration:
• MOD1 - To record the measured value
Input signals:
• Module 1 measured value recording
• Flow rate measurement (0/4 – 20mA) scalable
• second control variable is possible via sensor measuring
module
• internal or external dosing factor (0/4 – 20 mA)
The following controller outputs are possible:
• Dosing pump
• Pulse pump
• Positioner with feedback 1kOhm/5kOhm/0 –1 V/mA signal
• mA analog output
How the ratio
control works
The flow rate is recorded and the dosing capacity adjusted
proportionally to the flow rate using the flow rate sensor with linear
mA/V output signal.
On the settings for the flow rate signal see menu „Inputs/Outputs“
- “Flow Wq“.
D o s i n g
m g / l
0 , 0 0
1 . 0 0
0 . 4 3
0 , 6 5
1 2 : 3 5 M e a s . 1
M O D E C A L M E N U
D I
I
D I
I I
E S C
S e n s o r d
+ T e m p .
f l o w r a t e
S e n s o r
Q
1 x m A o u t p u t
2 x a l a r m r e l a y
2 x a l a r m / d o s i n g o u t p u t
f l o w r a t e
m A
f l o w r a t e