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<7. START-UP>
7-3
IM 11P03A03-01E 6th Edition : Jan. 26, 2022-00
7.4 Setting the Output Range
The three ranges should be preset to range 1, 2 and 3, respectively and one of the three ranges
should be selected. The following describes how to set each range and how to select a range.
(1) Switch to MAINT mode and enter the password.
(2) Change the Function Number to “12.”
(3) Set the upper range value for range 1 using the SHIFT and INCR keys. Press the EXEC key
to accept.
For example, for the range of 0 to 25% O
2
, enter “025.” Now range 1 is set to 0 to 25%.
(4) In the same manner, set the upper range values for ranges 2 and 3 in Function Numbers 13
and 14, respectively.
(5) Change the Function Number to “11.” Select the desired range – “1” for range 1, “2” for
range 2, or “3” for range 3 – using the SHIFT and INCR keys. Press the EXEC key to
accept.
7.5 Executing Calibrations
After start-up and switching to MEAS mode, zero and span calibrations must be executed.
Always a zero calibration should be performed prior to a span calibration. Chapter 13,
“Calibration” explains the calibration principle in detail. This section describes how to set the
concentrations of calibration gases and how to perform zero and span calibrations manually.
7.5.1 Calibration Gas Requirements
As the zero gas, use nitrogen with a minimum purity of 99.99%. As the span gas, use a gas with
an oxygen concentration of 80 to 100% of the upper range value of set range (e.g., for the range
of 0 to 25%, the span gas should be 20 to 25% oxygen).
7.5.2 Setting Calibration Gas Concentrations
(1) Switch to MAINT mode and enter the password.
(2) Change the Function Number to “02.”
(3) Press the SPAN key.
(4) Set the oxygen concentration of the span gas using the SHIFT, INCR, and DP keys. Press
the EXEC key to accept. The setting range is 0.5 to 25% O
2
.
7.5.3 Manual Calibration
A zero calibration should be performed first, and then a span calibration. Zero and span
calibrations must be conducted in the first calibration after start-up and after the initialization of
the calibration coefficient.
(1) Switch to MAINT mode and enter the password.
(2) Change the Function Number to “01.” The DATA display shows the current oxygen
concentration.
(3) Press the ZERO key. Turn off the sample gas flow and apply the zero gas at the specified
flow rate in the sample gas line. When solenoid valves for automatic calibration are installed,
pressing the ZERO key closes the solenoid valve in sample gas line and opens the solenoid
valve in zero gas line.
(4) The oxygen concentration on the DATA display changes. When the reading has stabilized
completely, press the EXEC key. The instrument is now calibrated to that value as the zero
point.