SIGNAL GROUP LTD
s/sales/masters/manuals/noxgman.doc Page 11 of 17
3.03
SPAN GAS CONNECTION
The span gas should be nitric oxide in nitrogen at a concentration about the level,
which you expect to use the analyser. The rear of the instrument has a 1/4”
compression fitting and you should use either Teflon (PTFE) or stainless steel
tubing. DO NOT USE NYLON OR COPPER TUBE.
Do not set the pressure to this line until you start to operate the instrument
because as soon as you set a pressure on the gas inlets, a flow will start to
occur.
3.04
OXYGEN/AIR INLET
Connect the oxygen or air cylinder to this connection, again using Teflon (PTFE)
or stainless steel tubing. It is most common to use oxygen but dry air can be
used with almost as high an ozone production as that using oxygen. Also, the
Signal Model NOXGEN III has been carefully designed so that no nitric oxide is
generated from the nitrogen in air, which means that converter efficiency testing
using air can still be done without inaccuracies. The only difference seen will be
the level of nitric oxide in the span gas which can be lowered in reading by
conversion to nitrogen dioxide, i.e. using air will allow you to change less NO to
NO2, using oxygen will allow you to change more NO to NO2.
3.05
OUTLET
This connection, again a 1/4” compression fitting, should have Teflon or stainless
steel tube connected to the calibration inlet port of the NOx analyser being
tested.
3.06
MAINS POWER
Connect a 220/240V or (110V if specified on rear panel nameplate) using a
properly grounded (earthed) supply. 1 amp is the MAXIMUM POWER
DEMAND.
