Panametrics XMO2 - 3.9 One-gas pushbutton field calibration; 3.10 Two-gas pushbutton field calibration

3.9 One-gas pushbutton field
calibration
This simplified field calibration procedure uses a single
(offset) gas to recalibrate the XMO2. Then, the XMO2
compares the data from this field recalibration to the
original factory calibration data, and stores the difference
as an Offset Curve.
The XMO2 is usually factory-programmed for the offset
gas pushbutton calibration method. The Calibration Sheet
shipped with your unit specifies the recommended oxygen
level (in %O
2
) for the offset gas to be used. This is the same
offset gas oxygen level that was used for the factory
calibration. If no offset gas %O
2
is specified on the XMO2
Calibration Sheet, the factory calibration was done with
100% N
2
(0.00 %O
2
) and the field calibration should use the
same offset gas.
To perform a pushbutton offset gas field calibration,
complete the following steps:
1. Verify that your XMO2 is configured for a one-gas
calibration. This is the factory default configuration for
all units.
2. Using the sample system controls, stop the flow of
sample gas to the XMO2 inlet port and initiate a flow of
the same offset gas specified on the XMO2 Calibration
Sheet. Establish the same flow rate and pressure
conditions used for the sample gas, and allow the offset
gas to flow through the XMO2 for at least three minutes.
3. Using Figure 11 on page 17 as a guide, locate the
Calibration Pushbutton (Switch S3). Depress the
Calibration Pushbutton and hold it down for 20 seconds.
During this time, the green light below the Calibration
Pushbutton will go out.
4. When the Calibration Push Button is released, the
green light will come back on and the XMO2 has been
recalibrated.
You may now return the XMO2 to normal operation by using
the sample system controls to stop the offset gas flow and
restart the flow of sample gas.
3.10 Two-gas pushbutton field
calibration
This simplified field calibration procedure uses two (zero
and span) gases to recalibrate the XMO2. Then, the XMO2
compares the data from this field recalibration to the
original factory calibration data, and stores the difference
as a Drift Curve.
Note: If the range of your XMO2 is 0 to 21% O
2
, you can use air
as the span gas.
3.10.1 Setup
Before proceeding, you must be sure that your XMO2
is configured for a two-gas calibration. The required
reprogramming must be done via the IDM communication
link, as follows:
1. Launch IDM.
2. From the Instrument window, pull down the Edit
Functions menu, as shown in Figure 12 on page 19.
3. Click on the Field Cal option. In the Field Cal window
(shown in Figure 13 on page 20), click on the Configure
Cal button.
4. In the Configure Cal window (shown in Figure 17 on page
21), click on the Field Cal Type button.
5. In the Field Cal Type window (shown in Figure 18 on
page 21), click on either the 1-Point or 2-Point button.
Then, click on any button on the right to return to the
Configure Cal window
Note: The zero and span calibrations can be performed in
either order. For zero-based calibration ranges (e.g., 0-25%),
we recommend performing the span calibration first. For
non-zero-based calibration ranges (e.g., 90-100%), we
recommend performing the zero calibration first.
Proceed to the appropriate section to begin the field
calibration.
3.10.2 Zero gas pushbutton calibration
To perform a zero gas pushbutton field calibration, complete
the following steps:
Using the sample system controls, stop the flow of sample
gas to the XMO2 inlet port and initiate a flow of the same
zero gas specified on the XMO2 Calibration Sheet. Establish
the same flow rate and pressure conditions used for the
sample gas, and allow the zero gas to flow through the
XMO2 for at least three minutes.
Using Figure 11 on page 17 as a guide, locate the Zero/Span
Selector (Switch S1). Set the Zero/Span Selector (Switch S1) to
position “1” (“Zero”).
Using Figure 11 on page 17 as a guide, locate the Calibration
Pushbutton (Switch S3). Depress the Calibration Pushbutton
and hold it down for 20 seconds. During this time, the green
light below the Calibration Pushbutton will go out.
When the Calibration Pushbutton is released, the green light
will come back on and the XMO2 has been recalibrated.
Verify that the mA reading on the ammeter is now equal to
the expected value.
IMPORTANT:
If the XMO2 fails to recalibrate to the correct analog output
value, contact Panametrics for assistance.
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