Teledyne API Model 401 O
3
Photometric Calibrator Instruction Manual, 01124, Rev. J1
2.2 Front Panel
This section describes the operator interface from the point of view of the front panel. The front
panel consists of a 2-line by 40-character alphanumeric display, 8 pushbuttons, and 3 status
LEDs. Each of these features are described in Section 2.2.1.
2.2.1 Front Panel Display
The display is divided into 4 main "fields": the
mode
field in the upper left, the
message
field in
the top center, the sample concentration field consisting of the most recent instantaneous ozone
value field in the upper right, and the MENU field which occupies the entire bottom line of the
display. A typical display is shown in Figure 2-1.
Figure 2-1: Model 401 Front Panel
The mode field indicates the current mode of the Analyzer. Usually, it shows "STBY ZS ",
indicating that the instrument is in the standby mode and that automatic zero/span checking is
enabled. Manual span checking or calibration can only be performed by pressing the buttons on
the front panel labeled "ZERO", "O
3
GN" or “ASEQ.” ASEQ is a sequence of multipoint
calibration which is displayed only if automatic multipoint sequence is selected (see Section 3.3
for detailed information). Automatic span check only occurs at the preset time. Calibration and
span adjustments are discussed in greater detail in Section 3.6. Table 2-2 lists all the possible
modes in the Analyzer and their meanings.
2-4
