Model 202 Ozone Monitor Manual Rev. J-4
17
Analog Inputs.
To turn the three analog inputs on or off, select the
V_IN
submenu. If
the analog voltage inputs are turned on you will see:
VIN Menu
Voltage In=ON
You may the use the Select switch to toggle between
ON
and
OFF
. If no analog
inputs are being used, it is advantageous to turn the analog inputs off in order to
increase the number of data lines that can be logged in the internal data logger and to
reduce clutter in the output data lines sent via the serial port.
Analog Outputs.
An analog output is provided via a BNC connector at the back of
the instrument for those who want to record their ozone concentration data with a
chart recorder or external logger. The full scale of the analog output is 2.5 V. To
change the analog output voltage scaling factor, select
V_OUT
from the
Ext
Menu:
VOUT Menu
1V= 00200 ppb
In this example, the output scaling factor is set as 1 Volt = 200 ppbv. Since the
maximum output voltage is 2.5 V, the maximum output concentration in this case is
500 ppbv, and 1 ppbv will provide an output of 5 mV. You can use the select switch to
change the scaling factor to the value of your choice by selecting and changing the
individual digits in the scaling factor.
3.18. To Turn the Display Light On and Off
Selecting
LCD
from the
Cfg
/
I/O
submenu allows you to turn the light of the front
panel display on and off. To conserve power, use the Select switch to set the
LCD
submenu to
OFF
.
3.19. To Change the Units for Internal Temperature, Pressure, and Ozone
From the
Cfg
menu, select
Unt
to give the following submenu, for example:
Units Menu
T/P O3
To change the units of temperature or pressure, rotate the Select switch until it is
under the
T
or
P
and push to select. Temperature units may be selected as either
Kelvin (
K
) or Celsius (
C
) by first clicking to obtain the blinking cursor and then rotating
the Select switch to obtain the desired units. Pressure units may be selected as either
torr
or
mbar
. A click on
returns the display to the
Unt
submenu. To change units
of ozone, rotate the Select switch until it is under the
O3
and push to select. Move the
cursor until it is under the first letter of the units and push to select. Rotate the Select
switch to scroll through the choices of units and push to select the desired setting. A
click on
returns the display to the
Unt
submenu.
