RKI Instruments GX-2012 Manual - Manual (Page 50)

42 • Inert Mode GX-2012 Operator’s Manual
Inert Mode
Inert Mode is used to measure the combustible gas and/or oxygen level in a
purged environment. In order for the instrument to operate in Inert Mode, the
oxygen alarm must be set to H-HH operation in which both alarms are
increasing. The oxygen Warning and Alarm points are factory set at 5.0% and
10.0%.
It is recommended that the %volume sensor be installed in a unit that is used
to monitor combustible gas during Inert Mode operation since it does not
require oxygen to work properly. The catalytic LEL sensor does not operate
at oxygen concentrations below 10% volume. If it is necessary to use the
catalytic LEL sensor during Inert Mode operation, a dilution fitting must be
installed. Installing a dilution fitting will affect the oxygen reading since
you’re introducing oxygen into the sample.
Alarms
The oxygen channel alarm points in Inert Mode are different from those in
Normal Mode. All other alarm point settings remain unchanged.
Since the application for Inert Mode is to detect a rising oxygen level in
purged environments, both oxygen alarms are set to rising. The factory set
alarm point is 5.0% volume for the Warning and 10.0% volume for the
Alarm. These alarm points are user adjustable in Maintenance Mode. See
“Updating the Alarm Point Settings” on page 120 for instructions to set the
alarm points.
Start Up and Operation
1. With the oxygen alarm pattern set to H-HH, start up the GX-2012 as
described in “Turning On the GX-2012, Normal Mode Only” on page 19.