Campbell Scientific CPEC200 Closed-Path Eddy-Covariance System - Manual (Page 33)

CPEC200 Closed-Path Eddy-Covariance System
Make sure there are no leaks in the regulators or the connections
to the valve module. For automatic operation, the tank shutoff
valves are left continuously open. A plumbing leak could cause
the contents of the tank to be lost.
When inlets are not in use, replace the Swagelok ® plugs to keep
the system clean.
Connect the valve module’s Analyzer outlet to the Zero/Span fitting on back
of the EC155 analyzer. Similar tubing (pn 15702) or pre-swaged tube
assembly (pn 21823-L) is recommended for this connection. The length of this
tube should also be minimized to reduce equilibration time.
If the CPEC200 has been configured with the six-valve module, additional CO
2
span cylinders may be connected to the additional CO
2
Span inlets on the valve
module.
Open the shutoff valves on the cylinders and set the pressure regulators for
10 ± 5 psig delivery pressure.
If you inadvertently adjust the pressure too high, you may need to
slightly loosen the tube fitting to bleed off the excess pressure.
Retighten the fitting when the proper setting is reached.
The H2O Span inlet is bypass equipped, allowing continuous flow. This inlet
can be connected directly to the output of a dewpoint generator. The bypass on
this inlet will avoid pressurizing the dewpoint generator.
Some systems, such as the AP200 CO
2
/H
2
O Atmospheric Profile
system, require a tee in the connection from the dewpoint
generator to bleed off excess flow and avoid pressurizing the
dewpoint generator. Do not use a tee to connect a dewpoint
generator to the CPEC200.
5.3 Wiring
5.3.1 Ground Connections
The CPEC200 system enclosure and the EC100 electronics must be earth
grounded as illustrated in FIGURE 5-6. Ground the tripod and enclosures by
attaching heavy gage grounding wire (12 AWG minimum) to the grounding
lug found on the bottom of each enclosure. The other end of the wire should
be connected to earth ground through a grounding rod. For more details on
grounding, see the grounding section of the CR3000 Micrologger Operator’s
Manual.
NOTE
NOTE
NOTE
NOTE
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