Table of Contents
Advertisement
12
Calibration (basic measurement comparison)
asic measurement comparison)
2-point calibration with buffer solution (e.g. pH 9 and pH 7)
point calibration with buffer solution (e.g. pH 9 and pH 7)
1.
Block the measurement water
2.
Separate the electrode cable from the device
electrode cable from the device
3.
Unscrew the pH electrode from the measurement chamber
Unscrew the pH electrode from the measurement chamber
4.
Rinse the pH electrode off with (distilled) water
Rinse the pH electrode off with (distilled) water
5.
Carefully dab the pH electrode dry using a towel (free from
Carefully dab the pH electrode dry using a towel (free from
grease and fuzz).
6.
Connect the electrode cable to the device
Connect the electrode cable to the device again.
7.
In the menu, select the function 2-point calibration pH
8.
Enter the pH value of the 1st buffer solution as the
Enter the pH value of the 1st buffer solution as the 1st
calibration value pH (e.g. pH 9)
9.
Dip the pH electrode into the 1st buffer solution
Dip the pH electrode into the 1st buffer solution
(e.g. pH 9) and stir carefully
10.
If the measured value displayed and the measurement signal
e displayed and the measurement signal
have stablised and are no longer changing in a relevant
have stablised and are no longer changing in a relevant
manner, then confirm the 1st calibration point by pressing Next.
manner, then confirm the 1st calibration point by pressing
11.
Remove the pH electrode from the 1st buffer solution
Remove the pH electrode from the 1st buffer solution
12.
Rinse the pH electrode off with (distilled)
Rinse the pH electrode off with (distilled) water
13.
Carefully dab the pH electrode dry using a towel (free from
Carefully dab the pH electrode dry using a towel (free from
grease and fuzz).
14.
Enter the pH value 2. Buffer solution as the 2nd calibration
Enter the pH value 2. Buffer solution as the
value pH (e.g. pH 7)
15.
Dip the pH electrode into the 2nd buffer solution
Dip the pH electrode into the 2nd buffer solution
(e.g. pH 7) and stir carefully
16.
If the measured value displayed and the measurement signal
If the measured value displayed and the measurement signal
have stablised and are no longer changing in a relevant
have stablised and are no longer changing in a relevant
manner, then confirm the 2nd calibration point by pressing Next.
manner, then confirm the 2nd calibration point by pressing
17.
Check the calibration results displayed and close calibration by
Check the calibration results displayed and close calibration by
pressing Ready.
18.
Place the pH electrode back into the measurement chamber
Place the pH electrode back into the measurement chamber
19.
Open the shut-off valves for the measurement water
off valves for the measurement water
1-point calibration to the pool water's pH value
point calibration to the pool water's pH value
20.
Take a water sample from the measurement chamber and
Take a water sample from the measurement chamber and
calculate the pH value using a photometer
calculate the pH value using a photomete
(phenol red method).
21.
In the menu, select the function 1-point calibration pH
22.
Enter the pool water's pH value calculated using the photometer
Enter the pool water's pH value calculated using the photometer
as the calibration value pH
23.
If necessary, enter a value for electrode slope or reset the value
If necessary, enter a value for electrode slope or reset the value
to default
24.
If the measured value displayed and the measurement are
If the measured value displayed and the measurement are
stable and are no longer changing in a relevant manner, then
stable and are no longer changing in a relevant manner, then
confirm calibration by pressing Next.
25.
Check the calibration results displayed and close calibration by
Check the calibration results displayed and close calibration by
pressing Ready.
12.2.2
Calibration errors
During calibration, various plausibility criteria are checked. If one of the
uring calibration, various plausibility criteria are checked. If one of the
criteria is not met, then a corresponding error message appears and
criteria is not met, then a corresponding error message appears and
calibration is not executed.
The following criteria have to be met for successful calibration:
The following criteria have to be met for successful calibration:
The offset calculated (zero point displacement) has to be in the range
ated (zero point displacement) has to be in the range
of ±1.00 pH. The offset is generally close to 0 for flawless electrodes.
of ±1.00 pH. The offset is generally close to 0 for flawless electrodes.
The electrode slope calculated must be in the range of 50.0 mV/pH to
The electrode slope calculated must be in the range of 50.0 mV/pH to
70.0 mV/pH. For flawless electrodes, the slope is generally between
70.0 mV/pH. For flawless electrodes, the slope is generally
55.0 mV/pH and 60.0 mV/pH.
For 2-point calibration, the two calibration values have to be at least
point calibration, the two calibration values have to be at least
0.50 pH apart. 2-point calibration with buffer solutions pH 7 and
point calibration with buffer solutions pH 7 and
pH 6.80, for example, is not possible.
point calibration pH
point calibration pH
User Manual PoolManager
12.3
Calibration chlorine (Cl) / bromine (Br)
Calibration chlorine (Cl) /
(just PoolManager
®
Calibration for free chlorine/bromine measurement is performed as 1
Calibration for free chlorine/bromine measurement is performed as 1-
point calibration. The pool water's DPD measured value is entered as
point calibration. The pool water's DPD measured value is entered as
a reference value. It can be calculated using a photometer.
a reference value. It can be calculated using a photometer.
Alternatively, a simple colour test can be used. However, this is not
Alternatively, a simple colour test
recommended due to the limited precision.
recommended due to the limited precision.
IMPORTANT NOTICE!
IMPORTANT NOTICE!
Calibration near to setpoint
Calibration near to setpoint
For reliable and precise calibration of chlorine/bromine
For reliable and precise calibration of chlorine/bromine
measurement, this has to be performed as close to the
measurement, this has to be performed as close to the
desired setpoint as
desired setpoint as possible.
• First bring the chlorine/bromine concentration in the
First bring the chlorine/bromine concentration in the
pool to the desired value (=setpoint) via manual
pool to the desired value (=setpoint) via manual
dosage or manual addition.
dosage or manual addition.
• Check the value via DPD measurement
Check the value via DPD measurement
• Do not perform calibration until the value in the
Do not perform calibration until the value in the
pool is close to the desired setpoint (permissible
pool is close to the desired
tolerance ca. setpoint ±10%)
tolerance ca. setpoint ±10%)
IMPORTANT NOTICE!
IMPORTANT NOTICE!
Calibration for bromine
Calibration for bromine
Bromine concentration and chlorine concentration can
Bromine concentration and chlorine concentration can
be calculated using DPD measurement. However, the
be calculated using DPD measurement. However, the
same colour on the DPD sample yields different values
same colour on the DPD sample yields different values
for chlorine and bromine.
for chlorine and bromine.
• If your photometer/colour tester is expressly
If your photometer/colour tester is expressly
designed for bromine measurement, then you can
designed for bromine measurement, then you can
use the bromine value read directly.
use the bromine value read directly.
• If your photometer/colour tester is only designed for
If your photometer/colour tester is only designed for
chlorine measurement, then you have to multiply
chlorine measurement, then you have to multipl
the chlorine value by 2.2 in order to obtain the
the chlorine value by 2.2 in order to obtain the
correct bromine value (e.g. DPD measurement for
correct bromine value (e.g. DPD measurement for
chlorine 1.0 mg/l
chlorine 1.0 mg/l
INFO
Internal 2-point calibration
point calibration
Even if you only have to enter one calibration point,
Even if you only have to enter one calibration point,
®
PoolManager
PRO
PRO internally performs a precise 2-
point calibration. The second calibration point used is
point calibration. The second calibration point used is
the zero point from the potentiostatic measurement,
the zero point from the potentiostatic measurement,
which is always nearly the same.
which is always nearly the same.
12.3.1
Execution
Chlorine/bromine calibration can be found in the following menu:
Chlorine/bromine calibration can be found in the following menu:
Calibration Cl/Br
Calibration is executed as follows:
Calibration is executed as follows:
Select calibration Cl
•
Calibration is a menu sequence, i.e. it goes through a series of
Calibration is a menu sequence, i.e. it goes through a series of
•
menus step-by-step.
12.3.1.1 Calibration input
The following parameters are displayed in the calibration menu:
The following parameters are displayed in the calibration menu:
Cal. Value Cl (DPD 1 value)
Enter the measured DPD value as the calibration value (calibrate
Enter the measured DPD value as the calibration value (calibrate
close to setpoint!).
Current Value Chlorine
This is the current measured value calculated using the parameters
This is the current measured value calculated using the parameters
from the last calibration, which are still valid. This value may devi
from the last calibration, which are still valid. This value may deviate
from the actual value under certain circumstances. It is only displayed
from the actual value under certain circumstances. It is only displayed
to give you a certain level of orientation throughout calibration.
to give you a certain level of orientation throughout calibration.
®
PRO)
PRO)
bromine 2.2 mg/l).
35
Advertisement
Table of Contents
