Model 408 NO Calibration Source Manual Rev. D-3
10
4.2.2 NO (Nitric Oxide Menu)
By selecting
NO
from the
Adv
menu the user may choose to output a constant NO
concentration. Upon selecting
NO
, the following submenu will appear:
Select Amount
NO= xxx
You may change the desired target NO concentration (20-1000 ppb) by selecting the
individual digits (
x)
and rotating the Select Switch to choose a values for those digits,
as described above for setting the calibration parameters. To start producing that
concentration of NO, click on
. The instrument will now output the selected
concentration of NO until you enter the menu again and change the target
concentration. As an example, the display may read as follows
Target= 150 ppb
delT=-0.1
▌▌▌
if you have chosen 150 ppb as the target concentration and the instrument needs a
few more seconds to reach that concentration (five bars).
The selected target NO concentration will remain in memory until the next time you
change it. Bear in mind that the instrument will output 20-1,000 ppb of NO reliably. It
is not recommended using the 408 for concentrations less than 20ppb (other than
zero) or concentrations greater than 1000 ppb.
4.2.3 Zer (Zero Menu)
Selecting
Zer
from the
Adv
menu allows the user to produce zero air from the 408.
This submenu provides a rapid way to produce air containing 0 ppb of NO. In this
mode, the photolysis lamp is turned off. When running zero air the 408 LCD will
display
Target= 0 ppb
delT=-0.1
▌▌▌
4.3
Reentering the Menu
The menu may be reentered at any time by holding in the Select Switch until the menu
appears.
4.4
Viewing of Flow Rates Outside of the Menu
It is easy to view the instantaneous air and N
2
O flow rates while outputting NO.
Simply rotate the Select Switch one click clockwise to view the N
2
O flow rate and one
click to the left to view the air flow rate. The flow rates are also displayed on the serial
output header.
