Q
EC
PH
250
1.05
7.6
A
F02
5.4bar
B
CAL
PROG
ALM
HIST
AUX
mS
m3h
CONT
ENT
Q
EC
PH
250
1.05
7.6
A
F02
5.4bar
B
CAL
PROG
ALM
CONT
HIST
AUX
mS
m3h
The necessary proportion of reagent to reach a certain pH will depend not only on his nature and concentration, but also on
the nature of the water to treat and of the rest of dosed products that they could influence this parameter. Next we detail the
status of values PpH advised for a fast answer and stability in the pH.
The following table for different acids is an approach of the value PpH for these acids according to the correction of
necessary pH (1 or 2 points of pH).
Table for phosphoric acid.
Table for sulphuric acid.
Note: The A column corresponds to the concentration of acid.
4-10
8-15
30-60
60-110
10-20
15-30
60-120
120-200
A
40%
10%
5%
1point 2 points
60%
3-8
6-15
30-60
60-110
8-15
15-25
60-120
120-200
A
50%
10%
5%
1point 2 points
80%
1-3
2-5
10-25
20-50
2-5
4-10
20-50
40-100
A
50%
10%
5%
1point 2 points
95%
Table for nitric acid.
3. CONFIGURATION
PIQ control mode for the pH adjustment is a PI algirithm conditioned by the water flow. By means of the PpH parameter the
system set an initial proportional dosage. Later on the controller modifies the dosing flow following a standard PI
adjustment.
PpH can only be activated by independent pumps (outputs type A to dosify acid). It gives a better stability of pH even with
very variable flow and gives a better answer of the system to reach and keep readings at Set Point value.
PARAMETERS OF CONTROL PIQ:
PpH=0
: PIQ disabled
PpH = 1-200
The variable PpH corresponds to the initial concentration of applied reagent, expressed in parts for 100.000.
Example: For a flow of 200.000 l/h of water and a PpH = 1, the proportional dosage of acid corresponds to: (1 / 100.000) x
200.000 l/h = 2 l/h
3.8.3.3 CONFIGURATION FOR A pH CONTROL IN PIQ MODE (PPH)
Q
EC
PH
250
1.05
7.6
A
F02
5.4bar
B
1
4
EC 31%
PH 86%
mS
m3h
INPUT A START A
INPUT B START B
OUTPUTS
Qtest = 0
A Tdelay 15s
B Tdelay 15s
PpH = 1
PEC = 0.00%
Change Units by pr/- and validate by ENT.
WATER CONTROLLER 3000
USER'S MANUAL
21
