Campbell IRGASON, Руководство по эксплуатации продукта

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The following examples show how to use Table A-1 (p. 60). To synchronize EC100 data to other
data logger measurements when the data logger scan rate is 25 Hz and the EC100 bandwidth is
set to 20 Hz (a 200 ms delay from
Table A-1 (p. 60)), delay the non-EC100 data by five data logger
scans. Similarly, for a 10 Hz data logger scan rate and the same 20 Hz EC100 bandwidth, delay the
non-EC100 data by two data logger scans to match the EC100 data. For the best synchronicity,
choose a data logger scan interval that is an integer multiple of the EC100 filter delay.
The EC100 measures gas and wind data at 60 Hz, and 60-Hz data are down-sampled to the data
logger scan rate through SDM communications (see
EC100 outputs (p. 27)). This process
synchronizes EC100 gas and wind data with other signals measured by the data logger to within
±8.33 ms (plus or minus one-half of the inverse of 60 Hz). Alternatively, when sending data to a
non-Campbell data acquisition system, the EC100 down-samples its USB and RS-485 outputs to a
user-selectable rate of 10, 25, or 50 Hz. Although the gas and wind data from the EC100 remain
synchronized, the user must consider the down-sampled output interval when synchronizing the
EC100 data with other measurements in their system. These slower output intervals increase the
asynchronicity of EC100 data with other system measurements.
FIGURE A-1. Frequency and amplitude response of EC100 filter at various bandwidths
IRGASON® Integrated CO
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O Open-Path Gas Analyzer and 3D Sonic Anemometer 59