LI-COR LI-830, User Manual

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Example 5: Computing cell temperature from a voltage output
Cell temperature ( T in °C) is calculated from the DAC output with the following:
2-12
where X
F
is the full scale temperature value that corresponds to the high voltage,
X
Z
is the temperature value that corresponds to the low voltage, V is the voltage
reading, and V
max
is the output range (either 2.5 V or 5 V).
Example 6: Computing cell pressure from a voltage output
Cell pressure (kPa) can be computed from a voltage output with the following:
2-13
where X
F
is the full scale pressure value that corresponds to the high voltage, X
Z
is
the pressure value that corresponds to the low voltage, V is the voltage reading, and
V
max
is the output range (either 2.5 V or 5 V).
Other options
Enable heater: The heater should be enabled to maintain the optical bench tem-
perature. Normally the optical bench will be about 51.4 °C. If you disable the
heater, the instrument will not perform as specified.
Pressure compensation: Pressure compensation should be applied to ensure that
the instrument compensates for changes in pressure. Disabling pressure com-
pensation will lead to less accurate measurements.
Enable pump: If your instrument is equipped with a pump, this box will be inter-
active. Check it to turn the pump on. Clear it to turn the pump off.
Filter: The digital filter instructs the instrument to average the readings. A value of
0 means no averaging, whereas a value of 20 instructs the instrument to average
the previous 20 seconds of measurements. Increasing the averaging time will
decrease the variation in each reported value, but will also reduce the instrument
response time.
Section 2. Configuring the gas analyzer
2-7 Other options