F-900 Instruction Manual rev. 1/16/2014
1554 NE 3
rd
Ave, Camas, WA 98607, USA Phone (360) 833-8835 Fax (360) 833-1914
[email protected] http://www.felixinstruments.com
23
Setup Calibration
Current Calibration Parameters and re-calibration steps for C
2
H
4
, CO
2
, and O
2
sensors can be found
in the Calibration Menu.
C2H4
Calibration
**Re-calibration or changes to any of the Calibration Parameters for
C
2
H
4
must be performed
under the supervision of a Felix Instruments Technician only.**
Calibration Parameters are set by a Felix Instruments Technician during factory calibration and are
specific to each instrument. The internal offset is the ADC voltage output from the sensor when no
ethylene is present, and gain is a measure of the ADC voltage output from the sensor in the
presence of ethylene. The RH and T slope and offset are applied to the ADC voltage to correct for
shifts in relative humidity and temperature that may occur during the sample period.
Offset Autocorrection
Offset autocorrection allows the unit to adjust the baseline, or zero, for the ethylene sensors, which
may drift from the zero set at the time of calibration. The most recent adjustments to the offset of
the high resolution and low resolution sensors, and the gain of the high resolution sensor, are
visible in this menu. The offset autocorrection procedure typically takes about 20 minutes and
takes place during “Sensor Stability”, the first screen when measurement mode is initiated. The
default interval between autocorrections is 24 hours for continuous use, or during the next start-up
for units that are not run continuously. If the unit is exposed to concentrations greater than 10 ppm
Calibration Parameters
Internal offset
Internal gain
Calibrated RH
Calibrated t
RH slope
RH offset
t slope
t offset
