Teledyne 9110T - Nitrogen Oxides Analyzer - Manual (Page 286)

Model 9110T NOx Analyzer Troubleshooting & Service
Teledyne Analytical Instruments 286
Table 12-9: Analog Output Test Function - Nominal Values Voltage Outputs
FULL SCALE OUTPUT OF VOLTAGE RANGE
(see Section 5.9.3.1 )
100MV 1V 5V 10V *
STEP % NOMINAL OUTPUT VOLTAGE
1 0 0 0 0 0
2 20 20 mV 0.2 1 2
3 40 40 mV 0.4 2 4
4 60 60 mV 0.6 3 6
5 80 80 mV 0.8 4 8
6 100 100 mV 1.0 5 10
* For 10V output, increase the Analog Output Calibration Limits (AOUT CAL LIM in the
DIAG>Analog I/O Config menu) to 4% (offset limit) and 20% (slope limit).
For each of the steps the output should be within 1% of the nominal value listed except for the 0% step,
which should be within 0mV ±2 to 3 mV. Ensure you take into account any offset that may have been
programmed into channel (See Section 5.9.3.9).
If one or more of the steps fails to be within these ranges, it is likely that there has been a failure of the
either or both of the Digital-to-Analog Converters (DACs) and their associated circuitry on the
motherboard. To perform the test connect a voltmeter to the output in question and perform an analog
output step test as follows:
DIAG
PREV ENTR EXIT
DIAG AOUT
SETUP X.X
EXIT
DIAG AOUT
· Pressing the “x%” button pauses the
test. Brackets will appear around the
value: EXAMPLE: [10%]
· Pressing the “[x%]” button resumes the
test.
Performs analog output step
test 0% to 100%
SETUP X.X
COMM VARS EXIT
SETUP X.X
CFG DAS RNGE PASS CLK EXIT
12.7.6.2. A/D Functions
The simplest method to check the operation of the A-to-D converter on the motherboard is to use the
Signal I/O function under the DIAG menu to check the two A/D reference voltages and input signals
that can be easily measured with a voltmeter.