29
MODEL 1054B C
SECTION 5.0
START-UP AND CALIBRATION
A. Two Point Calibration. (continued)
5.
Allow the sensor to acclimate to the solution. (The
temperature reading should be stable.)
6.
Press the
CAL
key.
15t
displays briefly (if
2nd
dis-
plays, press
CAL
again), then the Numeric
Adjustment window displays.
7.
SCROLL
(
é
) and
SHIFT
(
ç
) to display the grab
sample's conductivity value at 25°C as noted in
Step 2, then
ENTER
into memory.
8.
Adjust the sample's temperature to the other nor-
mal temperature extreme of the process. To raise
the sample's temperature, a hot plate with stirrer is
recommended. To lower the process temperature,
place the grab sample container in an ice bath.
9.
Allow the sensor to acclimate to the solution. (The
temperature reading should be stable.)
10. Press the
CAL
key.
15t
displays briefly (If
2nd
dis-
plays, press
CAL
again), then the Numeric
Adjustment window displays.
11.
SCROLL
(
é
) and
SHIFT
(
ç
) to display the grab
sample's conductivity value 25°C as noted in Step
2, then
ENTER
into memory.
The analyzer will then calculate the true cell constant
and the temperature slope then return to reading con-
ductivity. The temperature slope of the process can
now be read. Press the
CAL
key twice. The display will
show
SLP
briefly then the calculated slope for the two
calibration points. Place the sensor in the process,
then remove the analyzer from hold by pressing the
HOLD
key twice again.
The slope may be calculated from the following formu-
la:
% SLOPE/°C=
Conductivity T
max
(
Conductivity T
min
—1
)
∆
T
X100
Where: Conductivity T
max
is the conductivity at the
maximum process temperature, Conductivity T
min
is the
conductivity at the lower process temperature, and the
³T is the difference between the maximum and mini-
mum process temperature.
EXAMPLE:
% SLOPE/°C=
45K
(
35K
—1
)
X100
60-50=10
=2.8%/°C
B. Single Point Calibration - Slope Known.
This is
the recommended procedure for the initial calibration if
the temperature slope of the process is known.
If you do not know the exact temperature slope value,
but wish to approximate it, refer to the following guide.
However, the conductivity reading may have reduced
accuracy compared to the value if the procedure in
Section A is performed.
Acids: 1.0 to 1.6% per °C
Bases: 1.8 to 2.2% per °C
Salts: 2.2 to 3.0% per °C
Water: 2.0% per °C
1.
Press the
CAL
key twice. The analyzer will display
SLP
briefly, then show the temperature slope in
memory.
2.
SELECT
to change the value. The analyzer will
display
AdJ
briefly, then show the Numeric Display
window.
3.
SCROLL
(
é
) and
SHIFT
(
ç
) to display the proper
temperature slope for the process to be meas-
ured, then
ENTER
into memory.
4.
Obtain a grab sample of the process to be measured.
5.
Determine the conductivity of the sample using a
calibrated bench instrument or portable analyzer.
The instrument must be able to reference the con-
ductivity to 25°C or the solution must be measured
at 25°C. Note the reading. Insure that the analyzer
is in hold. Press the
HOLD
key twice and observe
the solid flag.
6.
Press the
PV
key once then press the
SELECT
key once.
Std
will display followed by the Numeric
Display with digit flashing.
7.
SCROLL
(
é
) and
SHIFT
(
ç
) to display the con-
ductivity value you noted in Step 5, then
ENTER
it
into memory.
8.
Install the sensor in the process, then remove the
analyzer from hold by pressing the
HOLD
key
twice.
The analyzer will calculate the true cell constant after
the initial calibration.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com