Calibration
4
Introduction
A number of parameters monitored by the AL250-V2 must be periodically calibrated
for optimum performance and accuracy. These are outlined below.
AL250-V2 Calibration
Parameter
Method of Calibration
Settings
Index
Number
Recommended
Calibration
Frequency
Feed Conductivity
Calibration with Conductivity
Standard Solution
23
One to Three
Months Depending
Upon Sample
Condition
Permeate
Conductivity
Calibration with Conductivity
Standard Solution
24
Feed Temperature
Span
Calibration to Known
Temperature
25
Six Months
Permeate
Temperature
Calibration to Known
Temperature
26
Conductivity
The conductivity inputs of the AL250-V2 should be calibrated using a known standard
solution. Value of the standard should be in the upper area of the range of the
conductivity being measured by the AL250-V2.
In cases of low conductivity (< 50 uS/cm) it may be necessary to calibrate the sensor
and its associated input channel in situ. This is done by following the same general
procedure as outlined below for calibration to a standard solution with one exception.
In situ calibration requires that the sensor be left mounted in the process line.
Instead of using a standard solution, a sample from the process line is tested with a
calibrated meter. This measured conductivity value of the process fluid is used in lieu
of a standard solution value.
The following procedure should be used for calibrating the AL250-V2 to a solution of
known conductivity.
Step One
– Rinse or soak the sensor in deionized water. Dry the sensor and place it
in a solution of known conductivity. This may be a standard solution provided a
laboratory supply company or a water sample which has been measured by a
calibrated conductivity meter. Make sure that the conductivity value of the calibration
solution is within the upper range of the AL250-V2 conductivity channel. Allow the
sensor to equalize to the solution temperature for a few minutes before proceeding
with the next step.
