Teledyne API Model 200AH NOX Analyzer Instruction Manual, 06492, Rev. G2 9-11 Table 9-3: Summary of Diagnostic Modes
DIAG Mode Description
SIGNAL I/O Gives access to the digital and analog inputs and outputs on the
V/F board. The status or value of all of the signals can be seen.
Some of the signals can be controlled from the keyboard.
Table 9-4 gives details on each signal and information on
control capabilities.
NOTE: Some signals can be toggled into states that indicate
warnings or other faults. These settings will remain in effect until
DIAG mode is exited, then the M200AH will resume control over the
signals.
ANALOG OUTPUT Causes a test signal to be written to the analog output DAC's.
The signal consists of a scrolling 0%, 20%, 40%, 60%, 80%,
100% of the analog output value. The scrolling may be stopped
by pressing the key underneath the % display to hold the
displayed value. The exact voltage values depend on the jumper
settings on the analog output buffer amplifiers on the V/F card.
DAC CALIBRATION The analog output is created by 4 digital-to-analog converters
located on the V/F card. This selection starts a procedure to
calibrate these outputs. Refer to Section 9.3.3.1 for a detailed
procedure.
TEST CHANNEL Using the test channel, it is possible to route some of the
internal analog signals out of the 4th analog output port. This
Diagnostic mode is useful for intermittent problems, since the
signal can be captured on a strip chart recorder and examined
for periods of fault conditions.
OPTICAL TEST Sets the M200AH into a known state and turns on an LED near
the PMT to test the instrument signal path. See Section 9.3.3.1
for details on using this test.
ELECTRICAL TEST Tests just the electronic portion of the PMT signal path. Used in
conjunction with optic test, see Section 9.1.3.2.
O3 GEN OVERRIDE This function controls the power to the ozone generator. Unlike
the other Diagnostic tests, O3 Gen Power remains in the state
(ON/OFF) you set it to even when Diagnostic mode is exited.
Function does not indicate status of generator.
RS-232 Causes a 1-second burst of data to be transmitted from the RS-
232 port. Used to diagnose RS-232 port problems. See Section
9.1.3.7, 9.3.2 for RS-232 port diagnostic techniques.