Campbell CPEC300, Руководство по эксплуатации продукта

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CPEC300/306/310 Closed-Path Eddy-Covariance Systems
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7.1 User-Initiated Zero/Span for CPEC310
Before beginning a user-initiated zero/span, the temperature of the valve
module (and scrub module if applicable) must be within operating range. Select
the submenu Valv Tmpr Ctrl (or Valv/Scrub Tmpr Ctrl if using the scrub
module), found under the Attendant Zero/Span menu by highlighting it and
pressing
Enter.
The display will show some read-only values of the module’s
temperature and whether it is within safe operating range. If the temperature is
out of range, scroll down to the variable called VAL T Ctl On (or V/S T Ctl
On if using scrub module) , press Enter, highlight TRUE, and press Enter.
This will enable the module’s temperature control. Continue to monitor the
module’s temperature readings shown in this menu until they are within
operating range.
Upon completion of a zero/span in a CPEC310 system, navigate
again to VAL T Ctl On (or V/S T Ctl On if using scrub module)
and set its value back to
FALSE
to save power.
7.1.1 CPEC310 Auto Zero/Span
To initiate the auto zero/span cycle or sequence, return to the Attendant
Zero/Span menu and select the menu Prfrm AUTO_ZS cycle . Once in the
menu, verify that the value for
CO2 Span Gas
matches the molar mixing ratio
in ppm of the CO
2
span gas. If it needs to be edited, highlight the variable,
press Enter , type in the correct value, and press Enter again to save. If the
user-entered CPEC310-related constants were set such that an H
2
O span would
be included in the automatic zero/span cycle (see TABLE 6-1 ,
Program
Constants ), also confirm that the value of H2O Span TDP , the H
2
O span gas
dewpoint temperature, is correct.
Next, highlight Pick AUTO_ZS , press Enter , make sure AUTO_ZS is
highlighted, and press
Enter
. This initiates the automatic zero/span cycle;
TABLE 7-2 shows the sequence and timing through the automatic zero and
span cycle. The progress of the cycle may be monitored on the CR1000KD
screen by watching Site and Sec On Site . Real-time values of CO
2
, H
2
O, gas
flow, and system diagnostic are also provided in the menu. Upon completion,
the value for variable Pick AUTO_ZS will return to FLD_MEA , indicating
that the system’s measurement mode has returned to normal EC field sampling,
and Site will return to fld smp , indicating all zero/span valves are closed and
ambient air is being pulled into the sample cell.
For more information on sampling modes, regimes, and sites, refer
to Appendix B , Sampling Site, Regime, and Mode
(p. B-1)
.
TABLE 7-2 . Site sequence and timing in the auto zero and span cycle. Timing
on most sites is determined by the user-set constant TIME_ZRO_SPN . Some
sites may also be skipped, depending on CPEC310-related constants set by the
user; see TABLE 6-1 ,
Program Constants
.
NOTE
NOTE