GX-2009 Operator
s Manual22
This sec tio n desc ribe s the o pe ratio n o f the GX- 2009 in Me as uring Mo de. It
explains how enter Display Mode to view the peak gas readings of the four
target gasses, the STEL and TWA re adings fo r H
2
S and CO, and the full
scale detection range value for each target gas. It covers important issues
re g arding c o mbustible g as detec tio n. It also c o vers alarm indic atio ns and
use of the aspirator adapter accessory.
Normal Operation
When the GX-2009 comes out of its startup sequenc e, see Start Up
o n pag e 18, it e nte rs Meas uring Mo de and is in no rmal o peratio n if no
alarm indications are taking place. It is advisable to perform a fresh air
adjustment when the GX-2009 c omes out of its startup sequence as
described in Start Up . If
Auto Zero Adjustment is set to On, be sure to
follow the guidelines in step number 8 in Start-Up on page
18.
In the Normal Operation Screen of Measuring Mode, the battery level,
time, and gas c oncentrations for each channel are displayed on the LCD.
The time is in the lo wer right c o rne r and the batte ry le ve l is in the lo we r
left c o rner. Co mbus tible g as is displaye d as a pe rc entag e o f the lo we r
explosive limit (% LEL), oxygen is displayed as a vo lume perc entage (vol% ),
H
2
S and CO as parts per million (ppm). The c o mbustible c hannel gas
name is CH
4
if it is c alibrated to me thane (CH
4
) o r HC if it is c alib rate d to
a another combustible gas. See Combustible Gas Detection on page
24
fo r a disc ussio n of the c o mbustible c hannel gas name and c alibratio n.
Operation
Display Mo de
Yo u c an ac c e s s Dis play Mo de while in Me as uring Mo de by us ing the
POWER MODE button. In Display Mo de yo u c an view and reset the peak
readings for each target gas, view the TWA and STEL values for CO and
H
2
S, and view the detection range full scale for each target gas.
STEL is an acronym for short-term exposure limit, and it is the average
reading of the target gas during the last 15 minutes. TWA is an acronym
for time-weighted average, and it is the average reading for the target gas
during the last eight (8) hours. If eight (8) ho urs has no t elapsed sinc e the
unit was turne d o n, the TWA is still c alc ulated o ve r eight ho urs, with the
mis sing time as signe d a ze ro (0) value fo r the reading s . Similarly, if the unit
has no t been on fo r 15 minutes, the missing time is assigned a 0 value and
the STEL is calculated over 15 minutes. The peak readings, STEL values,
and TWA values are cleared when the unit is turned off.
Operation
19
15
15
21
To Next Page
Loading...
Need help?
General
