ENERAC 700, Инструкция по эксплуатации

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5. The measured emissions must be between 20% and 100% of the calibration
span, which is the high-level calibration span gas. It is suggested that you
choose a high-level span gas that is as high as possible, up to 5 times the
expected emissions concentration, but do not exceed the range of the sensor.
6. Accuracy requirements are listed below. They are based on the selected
concentration of high-level span gas. All accuracy requirements must be
met for each test.
A. Calibration error: < 2% for each calibration span gas concentration
B. System bias: < 5% (difference between gas introduced at the
probe and also directly into the analyzer)
C. Drift: < 3%
D. Interference check: < 2.5% for the sum of all interfering gases
E. Analyzer resolution: < 2% of range
F. Data recording:
1 minute average, each run
Example:
If the analyzer has an NO range of 1,000 PPM and the measured NO emissions are
150 PPM, you can select a high level calibration gas up to 750 PPM NO. This is
your calibration span. Then the accuracy requirements are: Calibration error <15
PPM, System bias <37 PPM, Drift <22 PPM, Interference check <18 PPM,
Analyzer resolution <15 PPM.
This summary addresses many but not all of the requirements of EPA Reference
Method 7E.