CIRAS-3 Operation Manual V. 1.09
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Electrical and Pneumatic Connection between the CIRAS-3 and SRC-2 /
CPY-5
PP Systems introduced the SRC-2 Soil Respiration Chamber and CPY-5 Canopy Assimilation Chamber
in March 2016 for use with the CIRAS-3. Both can connect electrically directly to the “AUX” port on the
CIRAS-3 console (Auxiliary Probe Adapter not required). All pneumatic connections are identical as
described in the previous sections. The only other major difference between the SRC-1 and SRC-2 is
that the SRC-2 has a built-in sensor for measurement of air temperature near the soil surface (Tsurface).
Therefore there is no need to manually enter this value when using the SRC-2 Soil Respiration Chamber.
Like the SRC-2, the CPY-5 Canopy Assimilation Chamber also connects electrically directly to the “AUX”
port on the CIRAS-3 console. Other than the electrical connector, the CPY-4 and CPY-5 are virtually
identical form an operation standpoint.
Configuring the CIRAS-3 console for measurement of Soil Respiration or
Canopy Assimilation
As discussed earlier in this manual and from the main screen, select
Settings (F2)
to configure the
system for closed system operation by selecting the appropriate chamber (SRC-1 or SRC-2) Soil
Respiration Chamber. Note that the Settings and displays are almost identical for the SRC-1 and SRC-2
with the main difference being surface temperature (Tsurface). This value must be entered manually with
the SRC-1. The SRC-2 measures, displays and records this value automatically (Tsurface).
Water Vapor
Equilibrator
Gas In Gas Out
