Model 405 nm NO
2
/NO/NO
x
Monitor Manual Rev. D
14
where
NO2
(or
NO
) is the value most recently written to the logger,
CF
is the cell flow
rate,
O3F
is the ozone flow rate (if
NO
is being measured),
T
is the temperature in
Celsius (or Kelvin if selected), and
P
is the cell pressure in millibar (or torr if selected).
If averaging has been selected (see Section 4.5 below), then the first display above
will be replaced by:
AvgNO2= 56.7 ppb
-------------------------------------------------
LOG= 193:4
Tsc=111
14:49
04/07/2015
Again 193 refers to the most recent log number. The “4” in 193:4 refers to the number
of 5-s data points that have been measured so far for inclusion in the next average to
be displayed and logged. If 5-s averaging is used, this number will always be 0. If 1-
min averaging is used, this number will increment from 0 to 11; for 5-min averaging,
the number will increment from 0 to 59; and for 1-hr averaging, it will increment from 0
to 719. This number is displayed so that the user will know how many more 5-s
measurements need to be made before a new average is displayed and logged.
If there is a power failure while the instrument is in the logging mode, logging will
resume after power is restored. A note of
Data Interrupt
will be written to the logger prior to writing the first new data line. In the case of a
power failure, a data line may be lost because the microprocessor writes to the logger
memory in groups of two lines. All data residing only in the volatile memory of the
microprocessor are lost when power is interrupted.
The instrument can accommodate multiple data interruptions due to power failures.
For example, one can purposely switch the instrument off, move to another location
and restart logging simply by turning the instrument back on.
4.3. To Stop Logging Data
Hold the Select switch down to obtain the
Menu
. Go to the
Dat
submenu by clicking
on
Dat
. Choose and click on the
End
function. This will end data logging. You may
now transmit the data to a computer by clicking on
Xmt
(see below). Alternatively,
you may return to the
Menu
and resume measurements by clicking on
. The stored
data will reside in memory (even when new measurements are being made) and can
be transmitted using the
Xmt
function as often as you like. However, all stored data
are lost once logging is started again using the
Log
function. Thus, you should
always transmit your data to a computer before restarting logging.
