Thermo Scientific 43iQ, Instruction Manual

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Calibration
Calibration
4-6 43iQ Instruction Manual Thermo Scientific
Regulations typically require zero/span calibration when the instrument is
newly installed, moved, repaired, interrupted for more than a few days, or
when span or zero shift by more than 15%.
All gas must be supplied to the instrument at atmospheric pressure. It may
be necessary to employ an atmospheric bypass plumbing arrangement to
accomplish this. Refer to Figure 2–6 in the “ Installation and Setup ” chapter
for an example of an atmospheric bypass plumbing arrangement.
If a filter is used, all gas must enter the instrument through the filter.
Note
The calibration and calibration check duration times should be long
enough to account for the transition (purge) process when switching from
sample to zero and from zero to span. This transition time is the time
required to purge the existing air.
▲
Depending on the plumbing configuration and the instrument, data from
approximately the first minute of a zero calibration or check should be
disregarded because of residual sample air. Also, data from approximately
the first minute of a span calibration or check should be disregarded
because the span is mixing with the residual zero air.
▲
Use the following procedure to perform a zero/span calibration.
1. If the instrument is equipped with the optional zero/span and sample
valves, connect the zero and span gas to the rear panel bulkheads
labeled ZERO IN and SPAN, otherwise connect a source of vented
zero air to the SAMPLE bulkhead. The top right of the title bar
indicates which mode is active: ZERO, SPAN, or SAMPLE.
Note
Do not use nitrogen for zero air.
▲
2. To ensure that the zero air is being measured at atmospheric pressure,
check that the zero air flow reported by the analyzer is approximately
0.5 LPM. Actual zero air flow should be 0.8 LPM or more, with the
excess flowing out the atmospheric bypass.
a.
From the Home screen choose
Settings>Health Check>Status
and Alarms>Flow and Pressure .
b. Make sure that the reported sample flow is less than the actual zero
air flow.
Calibration