9
Gas Analyzer Operation
Manual Zero:
Any time after warm-up, you can zero the gas readings and calibrate O2
by pressing the
“Z”
button. If the pump is off, it will automatically start.
Note: The sample
probe should be removed from the tailpipe, when the unit is being zeroed.
Automatic Zero:
The analyzer will automatically zero as needed. If the analyzer does
not sense exhaust gases, the automatic zero procedure will begin. The Sample LED will flash
during this process. If exhaust gases are present, the analyzer will wait until the gases are
clear.
Low Flow Warning:
If gas flow into the bench becomes restricted due to clogged filters
or restricted sample hose, the
“HC”
display will show
“LO”
(Figure 13). The other gas dis-
plays will be blank. Check the sample hose for restrictions or kinks. If no problems are found,
check the filters. Begin with the External filter and then check the Internal filter. Keep in mind
the gas flows through the inside to the outside of the filter. The filter may look clean on the
outside, but be clogged on the inside.
Figure 13
Printing:
Connect a parallel printer to the 25 pin connector on the back of the analyzer.
Press the “P” button to begin the printing process.
Note: To avoid print communication
problems, connect and power on the printer first, then provide power to the analyzer.
Computer Connection:
PC software can enhance the diagnostic benefits of the ana-
lyzer. The analyzer can be connected to a PC using a 9 pin serial communications cable. EMS
offers software that will display the sample gases, graph data and record information. Using
the portable gas analyzer with a laptop will help diagnose problems that only occur when
driving. The EMS software will be discussed later in this manual.
