Model 306 Ozone Calibration Source Manual Rev. G-1
10
4.2
Configuration Menu (Cfg)
Selecting the
Cfg
submenu will produce the following display:
Cfg Menu
Cal Prg Sch D/T
where
Cal
is a submenu for entering the calibration menu;
Prg
is a submenu for
defining a programmed series of step ozone concentrations;
Sch
is a submenu that
allows the user to set the Model 306 to run an ozone step function once per day at a
chosen time; and
D/T
is a submenu for setting the date and time. The purpose of the
return symbol (
) is to return to the previous menu; i.e., depressing the select switch
when
is highlighted allows one to move one level up in the menu. The function of
each submenu is described below.
4.2.1 Calibration Submenu
Choosing the
Cal
submenu results in the following submenu:
Cal Menu
Vout O3_L O3_H
where
Vout
is a submenu for setting the voltage offset value and
O3_L
and
O3_H
are
submenus for setting the calibration factors for Ozone output.
Choosing
Vout
results in the following submenu:
Vout Offset Menu
Offset= xx mV
There is an inherent electronic offset in the analog output of the ozone level being
produced. The
Vout offset
can be adjusted so that zero ozone will provide a
measurable positive voltage. It is adjustable from -99 millivolts to 99 millivolts, and this
setting is used to adjust the voltage output downward to 0.05 V for zero ozone output.
Vout
itself can be used measure ozone concentrations, as well as to provide error
messages for diagnostic uses. More details are provided below in Section 6,
“Using
the Voltage Output.
”
In order to account for the small curvature in the plot of ozone concentration versus
lamp intensity, calibration parameters are entered into the instrument in two
concentration ranges: low (300 ppbv and below) and high (301-1000 ppbv). Choosing
O3_L
results in the following submenu for setting the zero offset and slope for ozone
output in the ranges of 0 and 30-300 ppb, for example:
O3L Cal Menu
Z= 2 S= 1.05
Choosing
O3_H
results in the following submenu for setting the slope and offset for
ozone output in the range of 301-1000 ppbv, for example:
O3H Cal Menu
Z= 1 S= 1.03
