GE XMO2, Руководство пользователя

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Field Calibration 4-7
September 2007
Two-Gas 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.
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 RS232 communication link, as follows:
1. Enter the XMO2 Basic Menu by slowly keying in [Shift]+[1] (if the
XMO2 is set up for Easy Menu Entry ) or
[Enter], [1], [2], [3]
.
2. One of the following initial menu options will appear:
3. If the Quick Offset? option appears above, see Chapter 6, General
Programming , for instructions on reconfiguring the XMO2 for a
two-gas calibration.
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.
Zero Gas Pushbutton
Calibration
To perform a zero gas pushbutton field calibration, complete the
following steps:
1. 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.
2. Using Figure 4-2 on page 4-4 as a guide, locate the Zero/Span
Selector (Switch S1). Set the Zero/Span Selector (Switch S1) to
position “1" (“Zero”).
3. Using Figure 4-2 on page 4-4 as a guide, locate the Calibration
Pushbutton (Switch S3). Depress the Calibration Pushbutton and
hold it down for 20 seconds.
BASIC MENU
Quick Offset? or Quick Zero?