Calibration, oxygen version – RKI Instruments Eclipse User Manual
Page 16

Eclipse Detector Head Operator’s Manual
16
Calibration, Oxygen Version
This section describes how to calibrate the oxygen version of the Eclipse. It includes
procedures to prepare for calibration, enter the Calibrate menu, set the zero reading, set
the response reading, and return to normal operation. See the previous section,
Calibration, Combustible and Toxic Versions
, for instructions to calibrate a combustible
gas or toxic gas Eclipse.
WARNING: The Eclipse is not an active gas monitoring device during the calibration
procedure. The 4-20 mA output signal will “freeze” at the level it was at
just before entering the Calibration Menu. It will not indicate current
readings until the Eclipse is in normal operation again.
Preparing for Calibration
NOTE:
The following procedure assumes the use of a calibration kit which includes a
100% nitrogen gas cylinder, zero air cylinder, fixed flow regulator, calibration cup
for the oxygen sensor, and a short piece of sample tubing to connect the regulator
to the calibration cup.
1.
Connect the regulator to the calibration cup using the sample tubing.
2.
Install the calibration cup over the detector, then screw the regulator into the 100%
nitrogen calibration cylinder.
3.
Allow 100% nitrogen to flow over the sensor for 1 minute then proceed.
Entering the Calibration Menu
1.
Press and release (cover and uncover) the optical switch with your finger 3 times and
then press and hold. After each press and release, a number will display in the upper
right of the LCD indicating how many times the sensor has been pressed and
released. If you press and hold your finger over the sensor, an “H” will appear in the
upper right indicating that you are pressing and holding.
2.
After 5 seconds, the following will display: CAL MODE HOLD SW. If you hold your
finger over the sensor for 5 more seconds, the following will display: RELEASE to
ZERO. Release your finger at this time and the current reading will display with the
message ZERO in the upper left of the display and an “R” in the upper right
indicating that the Eclipse is ready for a zero operation.
NOTE:
If there is no switch activity for 60 seconds while the screen indicates that the unit
is ready for a zero operation, the unit will return to normal operation.
Setting the Zero Reading
1.
Verify that the oxygen reading has stabilized.
2.
Press and release the optical switch once. The Eclipse will perform a zero adjust which
will take approximately 3 seconds and return to the ready screen.
3.
Unscrew the regulator from the 100% nitrogen calibration cylinder.
Leave the sample tubing connected to the regulator and the calibration cup.