RKI Instruments GX-2001 Manual - Manual (Page 33)

Model GX-2001 Operator’s Manual Calibration • 28
Auto Calibration
This section tells you how to calibrate the Model GX-2001 using the auto
calibration (AUTO CAL) menu.
Preparation
Before you calibrate the Model GX-2001, you must set the zero readings
as described in “Setting the Zero Readings for All Target Gasses.” You will
also need the supplies listed below. Calibration kits from RKI Instruments,
Inc. are available for this purpose (see “Parts List”).
• Either a 3-gas or 4-gas calibration cylinder with the following
recommended concentrations:
• 50% LEL methane (CH
4
)
• 12% oxygen
• 50 ppm CO
• 25 ppm H
2
S (4-gas cylinder only)
• Balance of nitrogen
• To carry out the calibration, you will need a fixed-flow regulator with a
flow rate of 0.5 LPM and non-absorbent tubing.
Setting Up the Model GX-2001 for Auto Calibration
WARNING: Calibrate the Model GX-2001 in a non-hazardous
environment.
1. Attach the adapter plate to the unit.
2. Attach the calibration tubing to the adapter plate, then attach the
opposite end of the tubing to the regulator.
Setting the Span Readings for All the Target Gasses
1. Make sure you have set the zero readings for all the target gasses and
have set up the GX-2001 for calibration as described in the procedure
above.
2. Turn off the Model GX-2001 if it is on.
3. With the GX-2001 off, press and hold the AIR button, then press and
hold the MODE/POWER button. Release both buttons when you hear a
“beep.” The LCD displays “CAL,” the battery level, and the time.
4. Press either the DISP or AIR button to select Auto Calibration Mode.
The word, “Auto” is displayed next to the battery icon at the top of the
LCD.