Teledyne 6020 - Photometric analyzer - Manual (Page 49)

Photometric Analyzer Operation 3
Part I 3-25 Teledyne Analytical Instruments
• Ranges that have the same lower limits but upper limits that differ
by approximately an order of magnitude
• Ranges whose upper limits coincide with the lower limits of the
next higher range
• Ranges where there is a gap between the upper limit of the range
and the lower limit of the next higher range.
Range schemes that are to be avoided include:
• Ranges that overlap
• Ranges whose limits are entirely within the span of an adjoining
range.
• Ranges where the zero is suppressed, is 1-10, 1-100, etc,
however, 80-100, 90-100 is ok where the zero gas is actually
100% concentration and the calibration is inverted.
• In Oil and Water applications, because the range and cell path are
pertinent to the water background and preparation of zero fluid
by the sample system, the autorange feature should not be used.
Only single range is recommended.
Figure 3-2 illustrates these schemes graphically.
Figure 3-2: Examples of Autoranging Schemes
0 0.01 0.1 80 90 100