Observing and Recording Leaf Gas Exchange
CIRAS-2 Operator's Manual Version 2.04
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Observing and Recording Leaf Gas Exchange
Checking the System with an Empty Cuvette
With the cuvette closed and without a leaf inserted, you should conduct a routine test to ensure that all
values are stable and that the desired control settings are achieved. Stablity is easily observed by a flat
(horizontal) profile of the colored plots as they progress in time across the display screen. Select and
observe only the measured parameters associated with CO
2
and water vapor from the „Select Variables‟
field: Cr, Cd, Hr, Hd.
Within several minutes a display similar to the one below should be observed, assuming the system has
been adequately warmed up and all steps in
(on page 18) have been carefully
followed:
Please note the following:
Cr (Reference CO
2
) value should be near your Setpoint value and stable (+/- 2 ppm).
Hr (Reference H
2
O) value should be at ambient and stable (+/- 0.2 mb).
Cd and Hd values should be stable at approximately 0.0 (+/- 0.5 ppm CO
2
/ 0.2 mb H
2
O).
Tc (Chamber Temperature) value should reflect your selected temperature value.
Tl (Leaf Temperature) value should be within approximately 1.5 °C of the Tc value.
Q (PAR) value should be near your Setpoint value (with attached LED light unit) or ambient (if no
light unit is not used)
Battery voltage for both the left and right batteries should be > 13.0 V if fully charged.
Current
plots
