Detcon 1000_CO2 - Manual (Page 20)

Model 1000 CO2
Model 1000 CO2 Instruction Manual Rev. 2.2 Page 16 of 28
1) Verify that the current calibration gas level is equal to the calibration span gas concentration. (Refer to
Section 5.2.3 Program Mode, “View Sensor Status”. The item appears as “CAL LEVEL @ ### %”.)
2) If the calibration gas level setting is equal to the calibration span gas concentration, proceed to item “3)”.
If the calibration gas level setting is not equal to the calibration span gas concentration, adjust the
calibration gas level setting so that it is equal to the calibration span gas concentration.
a) Enter the programming menu by holding the programming magnet stationary over “PGM 2” for 30
seconds until the display reads “VIEW PROG STATUS”, and then withdraw the magnet. Scroll
through the programming menu by momentarily waving the programming magnet over “PGM 1” or
“PGM 2”.
b) From the programming menu scroll to the calibration level listing. The menu item appears as: “SET
CAL LEVEL”. Enter the menu by holding the programming magnet stationary over “PGM 1” for 3
seconds until the display reads “CAL LEVEL @ ##%”, then withdraw the magnet. Use the
programming magnet to increase (PGM 1) or decrease (PGM 2) the display reading until the reading is
equal to the desired calibration span gas concentration.
c) Exit to the programming menu by holding the programming magnet over “PGM1” for 3 seconds.
d) Exit back to normal operation by holding the programming magnet over “PGM 2” for 3 seconds, or,
the sensor will automatically return to normal operation in 30 seconds.
3) Enter the calibration menu by holding the programming magnet stationary over “PGM 1” for 3 seconds.
The display will read “1-ZERO 2-SPAN”. Hold programming magnet stationary over “PGM 2” for 3
seconds, the display will change to “APPLY #.##% CO2”, withdraw the programming magnet. The #.##
indicates the gas concentration requested.
4) Turn the CO
2
3-way valve so that the arrow is pointing toward the cal gas source. The sample is now
being drawn from the CO
2
Calibration Port.
5) Turn the fixed flow regulator on the Cal Gas Bottle to the “ON” position, and set the sample Rotameter
flow valve so the flow is 250cc/min.
6) As the sensor signal changes, the display will change to “SPAN #.##%”. Where “#.##” indicates the
actual gas reading. The readings will increase/decrease until the sensor stabilizes. When the sensor signal
is stable, it will auto span to the requested concentration and the display will change to “SPAN
COMPLETE” for two seconds and then “REMOVE GAS”.
7) Turn the fixed flow regulator on the Cal Gas Bottle to the “OFF” position and remove the gas.
NOTE: If the circuitry is unable to adjust the span to the proper setting the sensor will enter into the
calibration fault mode which will cause the display to alternate between the sensor’s current status
reading and the calibration fault, which appears as: “CAL FAULT”.
8) Return the CO
2
3-way valve so that the arrow is pointing toward the sample source, and re-establish the
target sample gas flow through the sample Rotameter.
9) Span calibration is complete. The total time for span calibration is approximately 10 minutes. The
analyzer will then return to normal operation after the reading falls below the Alarm 1 and Alarm 2 set
point levels.
Additional Notes
a) Upon entering the calibration menu, the 4-20mA signal drops to 2mA and is held at this level until the
sensor returns to normal operation.
b) If during calibration the sensor circuitry is unable to attain the proper adjustment for zero or span, the
sensor will enter into the calibration fault mode, which will activate fault alarm functions and cause the
display to alternate between the sensor’s current status reading and the calibration fault screen which
appears as: “CAL FAULT”. If this occurs, attempt to recalibrate by entering the calibration menu. If the
sensor fails again, refer to Section 12.0, Troubleshooting.