GASMAX/TX Operation & Maintenance Manual, Revision 1.0
Page 30
1.
To enter CAL MODE, press the DOWN / CAL key and within 5 seconds press the EDIT key.
2.
The screen will display an APPLY ZERO message. Using the setup shown in Fig. 5-1, apply clean
ZERO air unless it can be guaranteed that no target gas is present. After the reading stabilizes,
press the EDIT key to complete the ZERO calibration.
3.
If the ZERO CAL SUCCESSFUL message is displayed, an APPLY SPAN message will appear. Apply
the correct SPAN gas. After the reading is stable, (approximately 1 minute) press the EDIT key to
complete the SPAN GAS calibration. If the SPAN calibration is successful, the display flashes
REMOVE CAL GAS and starts the CAL PURGE delay.
4.
Immediately shut off the regulator and remove the calibration cup. At the end of the CAL PURGE
delay, the GASMAX EC output is re-enabled and the unit is fully operational.
The flow chart shown in Figure 5-2 illustrates the above procedure. UP, CAL, NEXT & EDIT labels indicate
keystrokes using the magnetic wand. ZERO or SPAN calibration will fail if the readings exceed built-in
limits for maximum allowable zero or minimum allowable span.
NOTE:
A CAL MODE INFO SCREEN IS AVAILABLE TO VIEW CERTAIN CAL MODE PARAMETERS DURING
CALIBRATION. HOLD THE UP KEY FOR 5 SECONDS DURING CAL MODE TO DISPLAY THIS SCREEN.
Figure 9-2: CALIBRATION FLOWCHART
