Thermo Scientific iQ Series Instruction Manual page 104

Operation
Settings
3-78 42iQTL Instruction Manual
range is active, the range mode selection status output is at 0 volts.
When the high range is active, the range mode selection status output is
at half of full-scale.
When the high range is active, the NO concentration must drop to
85% of the low NO range for the low range to become active.
In addition to each channel having two ranges, each channel has two
span coefficients. There are two span coefficients so that each range can
be calibrated separately. This is especially necessary if the two ranges are
not close to one another. For example, the low NO range is set to 0–50
ppb and the high NO range is set to 0–200 ppb.
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