N
2
O Portable Monitor
Operation
Instruction 3015-4787
11
During normal operation the
Data Display
screen shows when the monitor is performing the following
two functions:
MEASURE
indicates that the monitor is actively measuring gas. In the screen shown above the monitor is
currently detecting 100 ppm of N
2
O gas. The
2ndUNIT
value (Blank, Peak PPM, Continuous TWA, or
8 Hr TWA) is user-selected (refer to
2ndUNIT
function on page 13). The measurement cycle runs for
4 minutes.
PURGE
is displayed when the monitor is resetting its infrared detector to a baseline of 0 ppm using the
fresh air in the monitor’s internal purge-air bag. The purge cycle runs for 10 seconds.
3.9.4 Function Screens
The Function
screens are used to set up the monitor and display stored data.
From the
Data Display
screen, press both
the
Keypad
Left
and
Right
buttons at the same time to
display the first
Function Menu
screen. Next, use the
Keypad
buttons to move the arrow (>) until it
points to the desired function, and then press the
ENTER
button to select that function.
Once a function has been selected, use the
Keypad
to scroll through the displayed data or to change a
parameter associated with that function. Press
ENTER
to save any newly entered parameters. Press the
ESC
button to return to the previous screen without saving.
Note that if no buttons are pressed within 90 seconds after selecting a function, the unit returns to the
Data Display
screen.
FILLBAG
– Press
ENTER
to manually fill the purge-air bag.
WARNING:
Fill the purge-air bag in a clean, fresh-air environment
that is at the same temperature and humidity as the area being
checked for gas. DO NOT fill the bag in an area that is
contaminated with N
2
O gas.
EMTYBAG
– Press
ENTER
to manually empty the purge-air bag. Use
this function to drain the bag if it becomes contaminated with gas.
ALRMLVL
– Detected gas level that causes the front panel
ALARM
(red) light to turn ON and the audible alarm to sound (if AUDALRM
function is set to ALARM or ALARM/FAULT).
AUDALRM
– The internal audible alarm is programmable to function as
follows:
•
OFF
– Audible alarm is disabled.
•
ALARM
– Alarm sounds when detected gas level exceeds the ALRMLVL level as evidenced by the front
panel ALARM (red) light turning ON.
>FILLBAG EMTYBAG
ALRMLVL
AUDALRM
>PPM LOG LOG INT
FAULTS
DIAG
>SILENCE P-CHK
GAS CLOCK
FILLING BAG...
DRAINING BAG...
AUDIBLE ALARM IS
ALARM
EDIT ALARM LEVEL
0300 ppm
>2ndUNIT PRINT
PLOT
PC-DUMP
