RKI Instruments GX-82 - Manual (Page 10)

6 • Operation Model GX-82 Instruction Manual
Normal Operation
The GX-82 continuously monitors the atmosphere and displays the LEL, O
2
, and H
2
S or
CO concentrations present. If the GX-82 is taken into a low-light environment, the display
backlight automatically turns on.
Displaying battery voltage
Press the BATT/DOSE button. A single tone sounds and the battery voltage displays.
New alkaline batteries will register approximately 3.0V; freshly recharged Ni-Cd batteries
will register approximately 2.7V. The minimum voltage required for the GX-82 is 2.3V.
NOTE: The GX-82 automatically checks battery voltage during start-up. If the
measurement is below 2.3V, the GX-82 will not operate.
During normal operation, when the battery voltage drops to 2.3V, the letter B
flashes on the display. When the voltage reaches 2.1V, all four LEDs turn on, a
continuous alarm tone sounds, and LOW BATT displays.
WARNING: The GX-82 does not monitor the atmosphere during the low battery alarm.
When the B indicator flashes on the display, take the GX-82 to a non-
hazardous location to change the batteries. (See Maintenance-Batteries.)
Displaying toxic gas (H
2
S and CO) exposure
Press the BATT/DOSE button until a double tone sounds. The GX-82 displays D= XXX
ppm *XXXM . This display indicates the H
2
S or CO average exposure ( D= XXX ppm ), and
duration of the measurement in minutes ( *XXXM ). The GX-82 returns to normal operation
after five seconds. The duration of the measurement is the time elapsed since the last time
the GX-82 was turned on.
Displaying peak hold
Press the PEAK/HOLD button. A single tone sounds and the letter P and readings for all
three gases display. While P is displayed, the GX-82 updates and displays the peak
reading (lowest for O
2
) for each channel since the time you pressed the PEAK/HOLD
button.
To return to normal operation, press the PEAK/HOLD button again. The GX-82 continues
to update and display peak readings until you return to normal operation or turn the
GX-82 off.
NOTE: The BATT (battery voltage) and DOSE (toxic exposure) functions do not work
while the GX-82 is in the PEAK hold condition.
Auto zero/span
To automatically adjust the zero point for combustibles, H
2
S or CO, and the span for
oxygen, take the GX-82 to a known fresh-air environment. With the GX-82 in normal
operation, press and hold the PEAK/HOLD button until a single tone sounds, then also
press and hold the BATT/DOSE button. The GX-82 displays
AUTO ZERO/SPAN , which
indicates the GX-82 is adjusting the detection circuits based upon the fresh air reading.
When
AUTO ZERO/SPAN displays, release the PEAK/HOLD and BATT/DOSE buttons.