Table of Contents
Advertisement
Chapter 5: Calibration and Verification
Certain recommendations can be made about the use of multi-point calibrations:
•
The concentrations of the points should extend beyond both ends of the expected concentration range
of the samples.
•
The accuracy of the calibration will be maximized when the concentrations of the points are close to
the concentrations of the samples.
•
It is recommended that the 5,000 ppm range and higher ranges be calibrated using at least two points.
•
If you plan to use the Auto Range feature, calibration of the 50,000 ppm range is important because the
preliminary measurement used to determine the appropriate analysis range is performed in this range. For
best performance of the Auto Range feature, it is recommended that the 50,000 ppm range be calibrated
using a six-point, point-to-point calibration. The recommended points are: Reagent Water, 100 ppm,
1,000 ppm, 5,000 ppm, 20,000 ppm and 50,000 ppm.
Auto Dilution
If you are calibrating with multiple points within a range, you can use one standard and the Analyzer will dilute it
for additional calibration points. For example, if you are calibrating in the Up to 1000 ppm range and want to
calibrate at 6 points, you could use a stock standard solution of 1000 ppm TOC. You can use the Auto Dilution
feature to dilute the standard to five additional points (such as 100, 250, 500, 625, and 750 ppm). Diluting
beyond 100 ppm would exceed a dilution ratio. of 10:1, which is not permitted. So, if you wanted to calibrate at a
point below 100 ppm via Auto Dilution, you must start with a standard less than 1000 ppm TOC.
GE Analytical Instruments ©2016
Figure 35: Point-to-Point Calibration with Six Points
113 of 270
DLM 68100-09 EN Rev. A
Advertisement
Table of Contents
